The ME program is sponsored by Regional Development Australia Hunter and the Department of Defence, Defence Materiel Organisation.

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1 Figure: (REA, 2012)

2 This document has been developed in cooperation with Re-Engineering Australia. Re-Engineering Australia Foundation was founded in 1998 by engineer, businessman and passionate Australian, Dr Michael Myers OAM, in response to the drastic shortage of skilled young people wanting to pursue engineering-technical-manufacturing career paths. Dr Myers linked with forward-thinking companies, organisations, government departments, educators and individuals who are passionate about enthusing, equipping and guiding our next generation. Many of the resources presented in this document have been developed by Re-Engineering Australia and the authors of this document wish to acknowledge the fantastic contribution that REA have had on the success of technology education throughout Australia. The Technological Literacy Group through their Science of Speed web site also kindly allowed the use of images and information for this document. The Technological literacy group is dedicated to STEM education based in the USA it provides excellent resources for CO 2 powered racing. Funding for the collation of this document has been provided by the ME program. This program is about creating a path for high school students to experience and explore the career opportunities that are possible in the manufacturing industry. These opportunities are delivered through a school program tailored to students from years Schools provide core subjects like Mathematics, English, Science, Information and Communication Technology and Engineering Studies to provide the foundations for pursuing a career in manufacturing. The ME program is sponsored by Regional Development Australia Hunter and the Department of Defence, Defence Materiel Organisation. The Living Toolbox is an initiative of the ME program which was developed to provide hands-on resources to support teaching and learning of advance manufacturing in our schools. This document has been prepared by Mr Ces D Amico and Mr Scott Sleap from Maitland Grossmann High, East Maitland NSW, Australia. Figure: (LAVC, 2012) The Living Toolbox CO 2 Powered Race Car Resource Folio 1

3 The Formula One Technology Challenge is an exciting, innovative and modern science, math and engineering action learning activity. With hundreds of schools Australia-wide already active, the F1inSchools program is ideal for all schools, being easy to integrate into a wide range of curriculum areas, or as an extra curricula activity. The competition revolves around teams designing making and racing C0 2 powered cars which have been machined from a balsa block using Computer Aided Drafting and Computer Aided Manufacturing techniques. This resource is based on preparing students to compete in this competition through the delivery of the NSW stage 5 Industrial Technology Engineering syllabus. Although this is the aim of this resource it is not necessary for the completion of this unit as a standalone engineering topic. The Living Toolbox website has been developed in conjunction with the ME program, to provide useful resources to assist teachers to effectively introduce advanced manufacturing concepts in the classroom. The ME program website has many resources for schools, industry and parents. It has been designed to assist participants in the program to reach the objects of the program. Re-Engineering Foundation hold the Australian licence for the F1inScools program and their web site and accompanying supportal has a vast array of resources which support the F1inSchools Technology Challenge (REA, 2012). The F1inSchool program is the world s largest Science, Technology, Engineering & Mathematics (STEM) Competition. It involves over nine million students from 17,000 schools in 31 nations. The DMO is part of the Department of Defence. In the Australian Government will spend more than $10 billion acquiring and sustaining military equipment and services. The DMO are major sponsors of both the F1inSchools and the ME programs. The Living Toolbox CO 2 Powered Race Car Resource Folio 2

4 Your Brief - You are the Formula One Team commissioned to design, construct and race the fastest Formula One Car of the Future, driven by new compact compressed air power plants. In order to complete this taks, you must work in a team of a minimum of 3 to a maximum of 6 persons, allocating job roles to the members of your group. Ideally, one role should be allocated to each person. However, you may have to double up on your role and responsibilities, depending on the number of people you have available. The following job roles should be covered by the members of your team: Team Manager (maximum 1 person). This person will be responsible for managing the team, ensuring that the primary and back-up cars are ready for the finals. The team manager works closely with all members of the team, offering assistance where necessary. Resources Manager (maximum 1 person). This person organises time, materials and equipment for design and making the cars. They are also responsible for developing ideas regarding team marketing (presentation). The resources manager will need to liaise with all members to check tasks are progressing on time and offer additional help, if needed. Manufacturing Engineer (maximum 2 persons). These people are responsible for advising team members on the manufacture of the car and the constraints of the machining process. Manufacturing engineers will need to liaise with the design engineers to report and help solve any problems with construction of the car. Design Engineer (maximum 2 persons). These people are responsible for the styling and aerodynamic performance of the car design. Design engineers will need to liaise with the manufacturing engineers to ensure their ideas can be realised. Graphic Designer (maximum 1 person). This person will be responsible for producing the colour schemes applied to the vehicle, including any special sponsorship decals, together with the final graphic renderings and any additional team marketing materials. The graphic designer will need to liaise with the design engineer to ensure any schemes will fit the shape of the vehicle and the resources manager for additional marketing development. There are so many tasks that must be mastered, in order to design, manufacture, prepare and finally enter a car for racing, that teamwork will be vital to your success. A real F1 team succeeds because all the people learn to work together and support each other. Remember, no one person is more important than another (REA, 2012). The Living Toolbox CO 2 Powered Race Car Resource Folio 3

5 One of the first tasks for this assessment task is to form into teams and assign roles. Firstly you and your team members need to understand what their role is and what has to be completed in each part of the process. HOWEVER, the best way to approach this project is the team approach with all members assisting each other and some members leading the work in the different areas. As you progress through the process, it will become apparent that some team members have skills in different areas and roles can be allocated accordingly. TEAM MANAGER Responsible for managing team to be ready for competitions. Works closely with all members. Checks all aspects of project. Responsible for organising sponsorship for teams. Spokesperson for team. RESOURCES MANAGER Liaises closely with team manager regarding team sponsorship. Responsible for organising team pit display materials and set up. Manages time, materials and equipment for team Develops ideas for marketing and industry links. MANUFACTURING ENGINEER Responsible for the construction and machining of the cars. Responsible for hand sanding, painting finish of car. Applies stickers to race ready car. Liaises closely with design engineer regarding design/manufacturing issues. DESIGN ENGINEER Responsible for the styling and aerodynamic performance of the car design. Responsible for the CATIA drawings of the car for manufacture. Evaluates, redesigns car to improve performance. Realises whole team vision for car. Understands and checks cars for compliance with rules. GRAPHIC DESIGNER Responsible for development of team emblem or logo. Responsible for development of team colour schemes and stickers. Produces additional marketing materials. Eg. shirts, caps, coasters etc Liaises closely with resource manager to develop team display. Responsible for final rendered graphics for project. (REA, 2012) The Living Toolbox CO 2 Powered Race Car Resource Folio 4

6 Your team must comply with all the guidelines outlined below: Your team must contain a minimum of 3 to a maximum of 6 students. Your team must use CAD (Computer Aided Design) software to produce your ideas and model them in 3D. Your team can use a CNC machine, such as a Denford Router or can be manufactured by hand to a high level of quality. Your car body must be manufactured from a single block of balsa wood. Each car body must be completed with a high quality painted finish. Each team must complete a design folder including initial ideas, design development and evidence of testing. Each team must supply (in the design folder) a dimensioned 3rd angle orthographic projection and a graphic rendering of their final design, both produced using an appropriate 3D CAD package. 1. All cars MUST be designed using CAD/CAM software. 2. The design of the completed car MUST resemble an actual race car, through the car being open wheeled such that wheel profiles are 100% visible and unobstructed from the side and above when the car is fully assembled. 3. The design MUST include a volume of virtual cargo positioned completely between the axles and side pod extremities. 4. The overall length of the complete car measured between the front and rear extremes of the car product, including all components with the exception of the CO 2 cartridge, MUST be a minimum of 150mm and a maximum of 215mm. 5. The minimum weight of the complete car product, without the CO 2 cartridge fitted MUST be 55g. 6. All balsa components for a completed car MUST be made from a single standard balsa wood blank as defined in these rules. Balsa is the default material for all non-rotating components of the car including the body and side pods. 7. Paint and other foreign materials MUST NOT be present inside the CO 2 cartridge chamber. 8. The cartridge MUST be able to be inserted and withdrawn without removal and replacement of car parts. The Living Toolbox CO 2 Powered Race Car Resource Folio 5

7 As you go through the process of designing your car, you will be using the same procedures which are used by actual car manufacturers. The basic process requires the designers to come up with concept ideas which are eventually refined over a series of steps in order to produce a model which is called a prototype. This prototype is then the car which is tested and continually refined before it is actually produced. As a designer you will also need to go through a series of design steps in order to turn your F1 in Schools racer ideas into reality. Before you can design your super-fast CO 2 powered car, however, it is imperative that you understand important fundamentals which are applicable to all objects that move. The Science of Speed website (PITSCO, 2002) is an excellent resource for learning about the science that underpins CO 2 racing. 1. Expanding Gas 2. Aerodynamics 3. Thrust 4. Inertia 5. Friction 6. Mass 7. Speed The site is dedicated to the pursuit of designing and building CO 2 -powered racecars and making them go fast. This is done by employing an understanding of physical forces at work. The authors of the web site have kindly given us permission to use some of their resources to learn about The Science of Going Fast. In this section we will learn about; F i g F F Figure: (PITSCO, 2002) The Living Toolbox CO 2 Powered Race Car Resource Folio 6

8 How does a CO 2 cartridge propel a car down the track? The answer has to do with Boyle s Law. Boyle s Law: Boyle's law was named after chemist and physicist Robert Boyle, who published the original law in The law itself can be stated as follows: Figure: (Creationtips, 2009) For a fixed amount of an ideal gas kept at a fixed temperature, P [pressure] and V [volume] are inversely proportional (while one doubles, the other halves). Figure: (PITSCO, 2002) Stated another way, if you double the pressure, you reduce the volume by half. See Boyles Law animation (Benson, 2007). This is exactly the case with CO 2 cartridges. At the factory, they are filled with pressurised carbon dioxide gas and then sealed. The CO 2 is confined to a small container; the volume of the gas would be much greater if it were released into the air. The large volume of CO 2 can fit inside the small cartridge because of the pressure that has been applied to it (PITSCO, 2002). Force: A force is something which can cause an object with mass to change its velocity, i.e., to accelerate. Force can also be described as a push or pull. A force has both magnitude and direction, making it a vector quantity. Newton's second law relates to force, F = ma. Push Pull Pressure: Figure: (REA, 2012) Pressure (the symbol: p) is the force (F) per unit area (A) applied. Its formula therefore; Atmospheric Pressure: The air around us is actually under pressure as well. Atmospheric pressure is 10.2 tonnes per square meter at sea level. Imagine a one meter cube of air. Now imagine a stack of one meter air cubes that reaches from the ground all the way to the edge of the Earth s atmosphere. That stack of air cubes actually weighs 10.2 tonnes. Figure: (uoregon, 2012) The pressure inside a CO 2 cartridge is far greater than atmospheric pressure. That s why the gas escapes so rapidly when the cartridge is punctured. The gas continues escaping until the pressure inside the cartridge equals the atmospheric pressure outside the cartridge (PITSCO, 2002). The Living Toolbox CO 2 Powered Race Car Resource Folio 7

9 Aerodynamics is the study of moving air and the forces that it produces. People who design things that move through the air, or have air move past them need to be familiar with aerodynamics. The study of airflow and the forces involved when an object moves through the air, or when air moves past an object is called aerodynamics. It is a fascinating subject as the forces that are generated can be large enough to enable extremely heavy objects such as a jumbo jet lift off the ground and to be supported by what would seem to be only thin air. The Wright brothers were the first people to design what we would consider to be a plane. Their designs on gliders and then for the first motorised flight became possible not only because of the experimentation they conducted in trialling gliders but also because of their experimentation that they carried out in the first wind tunnels. Figure: (old-picture.com, ) These wind tunnels are a very effective way of testing and predicting how objects will behave aerodynamically. They are actually a simple device, consisting of a closed type section through which air is forced by a fan. A scale model of an object is supported in the middle of the airflow and the flow of air can be measured by instrumentation if required as shown in the diagram below. Figure: (Cislunar, ) In the early days of aerodynamic research, as we do today, we are able to gain an understanding of how major factors of aerodynamics such as LIFT and DRAG affect and control objects which pass through the air. Through research using wind tunnels, scientists were able to determine that at low angles of incidence (which is the angle of a wing in relation to the ground), the lift to drag ratio of test surfaces could be very high. With this being the case, they concluded that wings could support substantial loads resulting in powered flight (OTEN, 2002). Figure: (Cetin, 2005) The Living Toolbox CO 2 Powered Race Car Resource Folio 8

10 They also discovered that the shape of wings determined the amount of lift that they could provide. Long narrow wings are able to provide more lift than short stubby wings of the same area. In order to make all of this research worthwhile, researches had to solve the problem of how all of this research of airflow in scale models was related to full scale aircraft cars etc. Figure: (Illusionist, 2011) Osborne Reynolds was one such researcher and he demonstrated that the airflow pattern over a scale model would be the same as that on a full scale version if the flow parameters were the same. Reynolds demonstrated that the motion of a fluid may be either laminar or turbulent. Figure: (Collier, 1904) Aerodynamics is widely studied in motor sport and in particular Formula 1 Racing. Projected Frontal Area The first important thing to know about aerodynamics is Projected Frontal Area. As your car rolls down the track and through the air it moves air out of its way. Projected frontal area is a measurement in square units that describes how much air an object moves as it travels. Think of it as the size of the hole that your car pokes through the air as it goes (REA, 2012). Figure: (REA, 2012) Types of Airflow As Reynolds discovered there are two types of air flow; laminar and turbulent. Laminar flow is when the air flowing around an object remains relatively smooth. The air flows in layers that never cross each other. In a wind tunnel sometimes tracks of smoke-like vapour are used to visualize the flow of air over an object. Where the tracks of vapour stay parallel to each other, there is laminar flow. Figure: (Barker, 2012) Turbulent flow is airflow resulting from the breakup of laminar flow, resulting in tumbling, swirling or violently agitated motion. In a wind tunnel using the vapour tracks, turbulence shows up when the smoke swirls or dissipates. Turbulent flow is created when the direction of laminar air flow is changed too drastically, and/or flows past an edge or corner of an object (Barker, 2012). Figure: (Barker, 2012) The Living Toolbox CO 2 Powered Race Car Resource Folio 9

11 See it in Action Sometimes when engineers use a wind tunnel they tape small lengths of ribbon at different places on the object being tested. The ribbon is taped down at the front end and left free at the other end. If the ribbon stays straight when air flows over the object, laminar flow is present at that point. If the tape flaps around wildly, then turbulent flow is present at that point. Click on the "wind tunnel" link to view a video of a model truck in a wind tunnel. Aerodynamics in Racing We now know that aerodynamics is the science that studies objects moving through air. It is closely related to fluid dynamics as air is considered a compressible fluid. Nowadays, aerodynamics is the utmost important factor in Formula 1 car performance. It has even nearly become one of the only aspects of performance gain due to the very marginal gains that can currently be made by engine changes or other mechanic component development. This down force can be likened to a "virtual" increase in weight, pressing the car down onto the road and increasing the available frictional force between the car and the road, therefore enabling higher cornering speeds. Computational Fluid Dynamic Systems (CFD) Furthermore, as Formula 1 teams have the greatest resources to develop aero efficiency of its cars, the greatest strives are made here. F1 teams have unrivalled CFD computing power and at least one full time wind tunnel only for validating and improving their designs. Figure: (DENFORD, 2012) While basic aerodynamic methods and formulas can be simply resolved, other properties are verifiable with empirical formulas. More complex shapes such as airplanes or racing cars are, however, impossible to calculate precisely, rendering computational fluid dynamic systems (CFD applications on super computers) and wind tunnels an absolute requirement to validate designs. Below is an example of the complex nature of airflow around an F1 car. This is mirrored in the CO 2 cars that are raced in the F1 in Schools competition and are determined by using the Virtual Wind Tunnel Software available through the competition. Figure: (Ryan, 2012) The Living Toolbox CO 2 Powered Race Car Resource Folio 10

12 Aerodynamic Forces In order to effectively design CO 2 cars which are aerodynamically sound, an understanding of the aerodynamic forces involved is important. Figure: (REA, 2012) Lift There are two main aerodynamic forces acting on any object moving through the air. Lift is a force that acts 90 to the direction of travel of an object. Usually we think of lift when we think of an airplane. The plane travels forward (horizontally), and lifts acts 90 to that motion of travel UP! Race cars use wings too. They turn those wings upside down so the lift becomes a downward force. It actually helps keep the car on the ground giving its tires much needed traction. Lift can only exist where there is laminar flow present. Figure: (Flightlearnings, 2012) Since the cars for our race will be propelled by the CO 2 cartridges rather than wheels being turned by an engine, and our cars will be controlled by being attached to a fish line, lift is of little concern to us (OTEN, 2002). Drag Drag is a force that is parallel to the motion of an object and directly opposes its motion. In other words, drag is a force that pushed back against an object in motion. Drag is affected by: Shape Surface finish Body protrusions Projected frontal area Speed. Figure: (REA, 2012) Anytime an object moves through the air, drag is generated. The more air that is turned and the more that the air is turned (read that again slowly) the more drag is generated. This is because the size and shape of the object affects drag (OTEN, 2002). The Living Toolbox CO 2 Powered Race Car Resource Folio 11

13 In the picture below, the moving air is turned as it hits the wing. Drag is generated. However, as the air passes the object and is allowed to flow back together, keeping its laminar flow, a pushing force occurs that counteracts some of the drag. Figure: (Adamone, 2012) To picture this push, think of pinching your fingers together on the back edge of a watermelon seed. The seed shoots forward, often hitting a little brother or sister in the back of the head. If laminar flow is broken, for instance if a wing has too high an angle, known as angle of attack, then turbulence eliminates that push and the overall effect of drag increases. Test Test Figure: (Adamone, 2012) Reynolds Numbers Osborne Reynolds was responsible for discovering many of the principles of fluid viscosity and boundary layers. He discovered that the condition of the boundary layer, laminar or turbulent, depend on the fluid velocity, the distance downstream, and a characteristic of fluid known as kinematic viscosity. Reynolds numbers are used to measure the viscous (Having a thick, sticky consistency between solid and liquid) qualities of a fluid. The symbol Re is used for this number and can be expressed as the equation: Re = V x s Where V = Fluid velocity d = distance downstream from leading edge = kinematic viscosity of the fluid (these are standard figures which are given with respect to air temperature) Figure: (Scott, 2005) At low Reynolds numbers the flow is laminar, and at high Reynolds numbers it is turbulent. Interested fact: Spheres are not a good shape for aerodynamics. A blade or fin or wing works much better at controlling air flow for flight by maximizing lift and minimizing drag forces. Dimples on a ball help reduce drag, while spin mostly promotes lift. Without dimples, golf balls wouldn't fly half as far as they do. The Living Toolbox CO 2 Powered Race Car Resource Folio 12

14 Form Drag The figure to the right shows how form drag (also known as pressure drag) is affected by the streamlined shape of the body. For a flat blocky shape, the form drag will be high and for a streamlined low-profile body, the form drag will be minimized. The separation of the fluid creates turbulence and results in pockets of low and high pressure that leave a wake behind the body, thus the term pressure drag. The pressure drag opposes forward motion and is a component of the total drag. Wake A wake is the region of recirculating flow immediately behind a moving or stationary solid body, caused by the flow of surrounding fluid around the body. The figure below shows the large wake generated behind the a small boat. This wake is in essence "wasted" energy that the ship generates. This wasted energy was not used to propel the boat forward, but rather to generate waves. Wake Turbulence Figure: (Cortana, 2006) Wake turbulence forms behind an aircraft as it passes through the air. This turbulence includes various components, the most important of which are wingtip vortices and jetwash. Jetwash refers simply to the rapidly moving gases expelled from a jet engine; it is extremely turbulent, but of short duration. See image below. Figure: (Edmont, 2009) Figure: (NASA, 1990) The Living Toolbox CO 2 Powered Race Car Resource Folio 13

15 Drag Coefficient The amount of drag on an object is proportional to the dynamic pressure times the area and will vary with the shape of the body, the roughness of the surface, and other factors. Drag, like lift, is proportional to the dynamic pressure of the air and to the area on which it is acting. Therefore, a drag coefficient is used to describe how much of the dynamic pressure is converted into drag. The equation looks a lot like the lift equation, except that it measures the force in a stream wise direction, which is parallel to the airflow. Drag= C d x (1/2 p V 2 ) x A Where: Figure: (Aquaphoenix, 2012) C - d = Drag coefficient - P= Density - V= Velocity - A= Area The term ½ p V 2, remember, is the dynamic pressure, referred to by the symbol q. Thus, using this notation: Drag= C d x q x A There is a similarity between lift coefficient and drag coefficient in that the lift coefficient, C L, is a measure of how much of the dynamic pressure gets converted into lift, and the drag coefficient is a measure of how well a wing (or other body) converts dynamic pressure force into drag. Both are an indication of efficiency. When generating lift, however, we want as much as possible, but, when generating drag, we want the least possible. A low drag coefficient, then, is what we want. The efficiency is determined by how little of the pressure force is turned into drag. The drag coefficient can also be expressed as the ratio of drag force to dynamic pressure force, or: C d = Drag/q x A Figure: (Magda, 2006) This is the formula that is used to calculate C D from wind tunnel tests. The drag force is measured using some sort of scale or balance. The force is then divided by q x A which is determined from a measurement of the air speed, density, and the area of the body. The Living Toolbox CO 2 Powered Race Car Resource Folio 14

16 Testing the Racer Shapes in a Wind Tunnel Using a wind tunnel to test different shapes and designs of our racer is a fantastic way to predict how our racer is likely to behave in an F1inSchools race. If we test our models in our wind tunnel and determine the different racer s Reynolds numbers we can determine the designs which create the least turbulence and therefore move with the best laminar airflow. Figure: (PITSCO, 2002) Obviously the designs with the lowest Reynolds numbers will then potentially be the fastest cars. Of course all other contributing factors between cars would have to be equal. We can use the Pitsco Scout, to test our racer designs. We can read the Reynolds number directly from the digital readout which makes this very useful for determining which of our designs is the best aerodynmically. Bernoulli's principle The production of the lift force by an aerofoil is explained by Bernoulli's principle. Daniel Bernoulli ( ) was a Swiss scientist who discovered that the total pressure in a fluid remained constant. This total pressure consists of: static pressure (the weight of the molecules) dynamic pressure (due to motion) Figure: (OTEN, 2002) If air was accelerated through a shaped tube called a `venturi', then at the narrowest point, where the speed of the flow was fastest, the static pressure was least. The relationship between the velocity and pressure exerted by a moving fluid is described by Bernoulli's principle (OTEN, 2002): as the velocity of a fluid increases, the pressure exerted by that fluid decreases. See Bernoullis s Principle Experiments YouTube Air foils and Lift Air foils are the wings on aeroplanes and the spoiler type sections on cars. In planes we all know that the wings allow the plane to be supported in the air, however on cars they are not just for show they have a very important purpose. In the diagram to the left differences in shape and the direction of the force produced is shown when the wing is inverted in powered car racing where the aim is to produce down force (so that the cars can stick to the road and grip so that the power produced by the engine can be transferred to the track). This is the direct opposite to a plane wing where the aim is to create lift to keep the plane in the air. The Living Toolbox CO 2 Powered Race Car Resource Folio 15

17 Angle of Attack If a thin plate is introduced into an airflow such that it was parallel to the air flow, it causes virtually no alteration to the airflow. As there is no deviation of the airflow, there is no force placed on the plate, and thus no reaction. If the plate is now inclined at an angle to the airflow (it is said to have an angle of attack), it will experience a reaction force on it. This reaction tends to lift it as well as drag it back. Due to the angle of attack, the straight-line streamline flow will be altered. The air below the plate will be compressed by the lower surface of the plate, whereas the air above the plate experiences a reduced pressure. The static pressure above the plate is now lower than the static pressure below the plate. This causes a net upwards reaction. After passing the plate, there is a downwash of the air stream. If the angle of attack is too steep, then the airflow will experience more disturbed air behind the plate and less lift will be evident. You can experience this when you hold your hand out of the window of a moving car. Change the angle of attack and your hand will experience different lift and drag reactions. These will depend on the speed of the car (or airflow) and the angle of your hand to the airflow (angle of attack). The total reaction on the plate caused by altering the airflow pattern has two components: lift - at right angles to the relative airflow drag - parallel to the relative airflow, and opposing the relative motion (OTEN, 2002). The Living Toolbox CO 2 Powered Race Car Resource Folio 16

18 Parts of an Air Foil The straight line connecting the leading edge to the trailing edge is called the chord line, and the distance between the leading edge and the trailing edge is called the chord. The angle of attack is measured between the chord line and the relative wind. Cambered air foils are usually to provide lift in a specific direction, usually upward on a conventional wing when the aim is to develop lift. All air foils are either cambered or symmetrical. These designs are shown below. Lift on cambered angles Notice that the cambered air foil above is at a zero angle of attack. A cambered air foil like this will produce some lift at this angle, because there is more area above the chord line than below, which causes a greater for the air flow. Figure: (MSulka, 2007) The Living Toolbox CO 2 Powered Race Car Resource Folio 17

19 Newton's Third Law of Motion Sir Isaac Newton s third law of motion states that for every action (or force) there is an equal reaction (or opposing force) in the opposite direction. Force Acceleration Figure: (MSulka, 2007) Action: CO 2 cars are propelled by carbon dioxide rapidly escaping from a small container. The CO 2 cartridge is positioned in the car so that the escaping gas moves in a rearward direction. The rearward force of the escaping gas is the initial action described by Newton. Reaction: The reaction part of Newton s law is fulfilled by the car s forward movement. Remember that the reaction occurs in the opposite direction: when gas escapes in a rearward direction, the car moves forward. As the car begins to move, its resting inertia is overcome. Newton's First Law of Motion "An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force." Objects tend to "keep on doing what they're doing." In fact, it is the natural tendency of objects to resist changes in their state of motion. This tendency to resist changes in their state of motion is described as inertia. As our F1 racers begin from rest. There is no motion and it will remain without motion unless it is acted upon by an external force. Figure: (MSulka, 2007) When we use the starting gates to launch our F1 Racer, we puncture the CO 2 canister in the rear of the car and this sets the car moving as the gas escapes from the canister. The force of the gas escaping in one direction causes an equal force in the exact opposite direction to move the car. With any outside forces the CO 2 car will never stop! Figure: (MSulka, 2007) The Living Toolbox CO 2 Powered Race Car Resource Folio 18

20 The tendency to resist changes in their state of motion is described as inertia. Inertia Inertia is the resistance of any physical object to a change in its state of motion or rest, or the tendency of an object to resist any change in its motion. In other words the greater the mass of your CO 2 car, the more energy required to get the car moving. If two cars use the same amount of propulsive energy, the car with the lower mass will accelerate faster. CO 2 racers through the eyes of Newton In a CO 2 car race, the dragster begins at rest. There is no motion. According to Newtons first law, it will remain at rest until and outside force acts upon it. Figure: (Holden, 2011) When the starting mechanism is activated the CO 2 cartridge is punctured, many types of outside forces will begin working on the car. First of all, when the cartridge is punctured, the pressurized gas inside begins to escape from the hole in the cartridge. The action of the CO 2 gas escaping out the back of the cartridge (according to Newton s third law) causes an equal and opposite reaction which is to move the dragster in the opposite (forward) direction. Figure: (Holden, 2011) This equal and opposite reaction creates a force that pushes the car forward. The force continues acting until the CO 2 gas in the cartridge has been exhausted. According to Newton s second law, the acceleration of an object is inversely proportional to its mass when force is constant. That means that if the amount of force is equal for each cartridge (which it is), then the more mass the dragster has, the less acceleration. The greatest determining factor for the success of a CO 2 car is its mass. It is critical that the mass of the car be as close to the minimum mass as possible. That will provide the greatest amount of acceleration. There are forces at work besides that of the racer being propelled forward, constantly trying to slow the racer down. These are FRICTION and AERODYNAMIC DRAG. The sum of all of these forces acting on the racer is termed the net force (Holden, 2011). The Living Toolbox CO 2 Powered Race Car Resource Folio 19

21 Energy The subject of friction is a terrific way to illustrate that energy cannot be created or destroyed. As a CO 2 dragster travels down the track it has mechanical energy, that is the energy of a moving object. Heat energy is a form of energy that comes from the random movement of its particles i.e. atoms and or molecules. Think of it as energy related to an object's temperature. Figure: (PITSCO, 2002) Friction Friction is a force that is generated when two or more surfaces come in contact with each other. The force resists the movement of the surfaces and converts mechanical energy into heat energy. In practical terms, it steals speed and turns it into heat. Friction Acceleration Figure: (MSulka, 2007) We do not want CO 2 cars that are hot (in terms of temperature). We want CO 2 cars that are fast. Therefore, we want to reduce friction in our CO 2 cars as much as possible. Two types of friction come into play with CO 2 cars: surface friction and fluid friction. Both of these are inversely proportional to speed! Surface Friction Depending on a CO 2 car s design, friction may occur between the wheel and axle, the axle, and body material. An often overlooked fact: Smaller diameter wheels rotate more times as they travel a given distance than larger diameter wheels do. Therefore, friction is more prevalent with smaller diameter wheels. Friction also occurs between the wheel and the track surface. In a passenger car, friction between the tire and road surface gives you traction, which is a good thing. The wheels, however, do not propel a CO 2 car, so the less wheel/road surface friction, the better. While friction may be reduced for better performance, it cannot be totally eliminated. Figure: (Glimmerveen, 2009) The Living Toolbox CO 2 Powered Race Car Resource Folio 20

22 Fluid Friction As the CO 2 car travels down the track, it moves through a fluid. Most people do not think of air as a fluid, but it is. While in motion, the CO 2 car s surface contacts air molecules. Because there is relative motion between the car and air molecules (the car is in motion while the air is stationary), friction occurs. Fluid friction contributes to drag, which is a resistance to the forward motion of a body through a fluid (the air). Figure: (PITSCO, 2002) Automotive engineers test their designs in wind tunnels. A wind tunnel simulates road airflow conditions by moving a stream of air around a stationary car. The speed of the moving air can be varied from very slow speeds to fast highway speeds. Figure: (PITSCO, 2002) Wind tunnels produce a laminar airflow. Laminar flow is a straight, layered flow of air without turbulent air pockets known as eddies. It is desirable for a car in the tunnel to disturb the laminar flow of air as little as possible. The presence of turbulence increases the aerodynamic drag, which resists the car s forward motion. Figure: (PITSCO, 2002) Surface friction and fluid friction also come into play as the inertia of the stationary car is overcome. If the masses of two cars are equal, then the winner will likely be the car with the least friction (PITSCO, 2002). Wind Tunnels A wind tunnel is a tool used in aerodynamic research to study the effects of air moving past solid objects. A wind tunnel consists of a closed tubular passage with the object under test mounted in the middle. A powerful fan system moves air past the object. CO 2 racers can also test their cars in wind tunnel which measures the frontal drag force. Figure: (PITSCO, 2002) The Living Toolbox CO 2 Powered Race Car Resource Folio 21

23 Smoke Tunnels Smoke tunnels introduce a visible vapour into a test chamber, clearly indicating any turbulence generated around the car body. Below is a smoke Flow Visualisation test undertaken by AC Racing for the F1inSchools competition. Figure: (PITSCO, 2002) Figure: (REA, 2012) Reducing Friction in a CO 2 Car There are a number of ways to reduce friction between rubbing surfaces, below is a summary of the main methods. Reduce If friction is created by rubbing surfaces, simply get rid of rubbing surfaces. Of course you cannot eliminate all rubbing surfaces, but you might be able to eliminate some or reduce the amount of surface-to-surface contact. Figure: (REA, 2012) The Living Toolbox CO 2 Powered Race Car Resource Folio 22

24 Material Selection Some materials generate more friction than others. For instance a piece of wood rubbing against a piece of metal may cause more friction than plastic against wood, or metal against metal. Choose materials wisely when parts will rub against each other. Material Preparation Figure: (REA, 2012) Even smooth looking surfaces have microscopic roughness. Sometimes preparing a surface by polishing it can smooth out a lot of microscopic roughness and reduce friction. Figure: (REA, 2012) Lubrication Lubrication means that a slippery substance, like oil or grease, is placed between rubbing surfaces to make them slippery. Some lubrication can be dry like powdered graphite, which is often used in pinewood derby cars to lubricate the wheels around their axles. Bearings Bearings are parts that support moving parts while allowing their free motion. Many times this will involve small balls or rods (ball bearing or roller bearings) that roll between two surfaces. Sometimes they are just parts that keep a small coating of lubricant between the rubbing surfaces. Bearings are made very precisely, so they tend to be expensive. So friction isn't such a bad thing if you are trying to stop a car, but we're racers! We are not interested in stopping but GOING! Click for bearing animation. Figure: (REA, 2012) Mass and Weight The mass is a measure of the amount of matter in the object. The usual symbol for mass is m and its SI unit is the kilogram. While the mass is normally considered to be an unchanging property of an object, at speeds approaching the speed of light one must consider the increase in the relativistic mass. The weight of an object is the force of gravity on the object and may be defined as the mass times the acceleration of gravity, If an object has a mass of 1 kg on earth, it would have a mass of 1 kg on the moon, even though it would weigh only one-sixth as much. The Living Toolbox CO 2 Powered Race Car Resource Folio 23

25 What Do We Need to Know About Mass to Design Fast CO 2 Car? The first important thing to remember about mass when designing dragsters is that it is easier to push a smaller mass than a larger one, remember the work on inertia. All CO 2 cars will be powered with an identical force. Basically you all will be using the same engine a CO 2 canister. You will gain an advantage over your competitors by concentrating on streamlining, reducing friction and reducing mass. There is an equation that expresses how mass, force and acceleration are related. The amount of Force is equal to the mass of an object times its acceleration. Or... F M a Acceleration means how fast the CO 2 car increases its speed. If your CO 2 car increases its speed by 10 meters per second every second, you would say that its acceleration is 10 meters per second per second. You would write that as 10m/s 2. If you want to see how mass affects your dragster's acceleration we can change the equation to this: m F a If the CO 2 is propelled with a force of 20 Newtons (20N) and the dragster's mass is 2kg, then the dragsters acceleration will be 10m/s 2. F a m 20N 2 10 m/ s 2kg If you cut more wood away from your CO 2 car and reduced your mass to 1kg look at what would happen to your acceleration. 20N 2 20 m/ s 1kg By cutting your mass in half, you double the acceleration If less mass was always faster and always better, then why not tape a CO 2 cartridge to a toothpick? A toothpick is pretty tiny in diameter. What do you think would happen to it when it hits the finish line, which is a block of wood? Eliminating too much mass makes your CO 2 car weaker. If your CO 2 car breaks at the finish of its first race, it won't be able to race in the next round. In other words; you lose. This is where the art of trade off comes into play. Mass should be reduced as much as possible without sacrificing the strength the CO 2 car needs to keep from breaking. A good designer (you) will determine how much mass should be eliminated and where on your dragster you should eliminate it. Figure: (REA, 2012) In a nut shell, less mass will accelerate faster than more mass. Too little mass will break too easily. It is your job as a designer to make the trade-offs that you think are right to get a dragster that will accelerate quickly without breaking at the end. All of these factors must be considered when designing a CO 2 car in order to achieve the best possible result. The Living Toolbox CO 2 Powered Race Car Resource Folio 24

26 How fast is your CO 2 car going? Calculating the speed (average speed) of a CO 2 car is pretty simple. The formula is: Average Speed = Distance/Time Figure: (REA, 2012) To plug in some numbers, our distance will be 25 Meters (m) (official distance) and our time will be 1.11 seconds (s) (a pretty fast race time). 25 m/1.11 s = m/s To convert your speed to kilometres per hour (kph) we have to know a few things. There are: 1000 metres in a kilometre 3600 seconds in an hour Plug in those numbers and we can figure out the speed in kph m/s x 3600 s/1000m = 81 kph Our CO 2 car is roughly 1/20th the size of a F1 racing car. If it were full size, it would be going almost 1620 kph! (20 x 81 kph) Figure: (REA, 2012) The Living Toolbox CO 2 Powered Race Car Resource Folio 25

27 An excellent way to start any design work is to see what has already been produced. As a starting point for your racer, research various CO 2 cars using the F1inSchools website, Google images, Flickr, etc. From the F1inSchools resources provided look at a number of sample folios to gain a better appreciation of good CO 2 car design. Once you have completed this research, copy and paste two car designs which your team are interested in the spaces provided on the next page. Complete an analysis of these two cars in the same fashion as shown below. Aerodynamics The car appears to be very aerodynamic, with smooth lines which would easily cut through the air as it speed down the track. The centre barrel is pointed in the shape of a bullet. Manufacture The redline racer has been manufactured using a Denford CNC mill, using 3D CAM/CAM technologies. The car has been sprayed with soft putty before being painted. Engineering This car demonstrates a high level of engineering, from it futuristic front and rear wings to it purpose built, light weight wheels. This car appears to be an engineering marvel. Aesthetics This particular car has a very distinctive look. The red and white colour scheme provides clean sleek lines. The shape is pleasing to look at and the decals make the car look like a racing car. The Living Toolbox CO 2 Powered Race Car Resource Folio 26

28 Thumbnail Scaling The object of this section is to learn how to resize or scale thumbnail sketches so that you can attain a full size sketch of your CO2 car designs. First though we need to learn a little about what scale is. Scale is a method that is used to resize objects to make them larger or smaller both as drawings and in reality. For example when we draw houses they are obviously too large to fit on a page so we can accurately resize them to include all the details using scale. When we use scale the great advantage is that all things that are to scale remain in proportion. In the drawing below, as you can see the car on the right is much larger than the one on the left even though they are the exact same drawing. However, the proportions are the same. The wheels are as far apart on both drawings as an example. A drawing of a real car cannot be of the same size as the car it represents. So, the measurements are scaled down to make the drawing of a size that can be conveniently used by users such as car manufacturer. A scale drawing of a car (or building) has the same shape as the real car (as above ) that it represents but a different size. A ratio is used in scale drawings of maps, buildings and cars. That is: The scale of a drawing = Drawing Length : Actual Length A scale is usually expressed in one of two ways: using units as in 1 cm to 1 km without explicitly mentioning units as in 1 : 100. A scale of 1:100 means that the real distance is 100 times the length of 1 unit on the drawing (Holden, 2011). The Living Toolbox CO 2 Powered Race Car Resource Folio 27

29 Since it is not always possible to draw on paper the actual size of real-life objects such as the real size of a car, an airplane, we need scale drawings to represent the size like the one you see below of a F1 car. Length In real-life, the length of this van may measure 4800 mm. However, the length of a copy or print paper that you could use to draw this van is a little bit less than 300mm Since 4800/300 = 16, you will need about 16 sheets of copy paper to draw the length of the actual size of the F1 car. In order to use just one sheet, you could then use 1 mm on your drawing to represent 20 mm on the real-life object. You can write this situation as 1:20 or 1/20 or 1 to 20. Notice: The first number always refers to the length of the drawing on paper and the second number refers to the length of real-life object Suppose a problem tells you that the length of a vehicle is drawn to scale. The scale of the drawing is 1:20. If the length of the drawing of the vehicle on paper is 240mm, how long is the vehicle in real life? Set up a proportion that will look like this: Do a cross product by multiplying the numerator of one fraction by the denominator of the other fraction. We get : Length of drawing 20 = Real length 1 Since length of drawing = 240, we get: = Real length mm = Real length The Living Toolbox CO 2 Powered Race Car Resource Folio 28

30 The scale drawing of this tree is 1:500. If the height of the tree on paper is 50mm, what is the height of the tree in real life? Set up a proportion like this: Do a cross product by multiplying the numerator of one fraction by the denominator of the other fraction We get : Height of drawing 500 = Real height 1 Since height of drawing = 50, we get: = Real length mm ( 25metres ) = Real height (Holden, 2011) To be able to effectively draw your CO 2 racer, you first need to understand that in drawing we use a type of projection called orthogonal to draw how things look from the top, front and side. To the right is an object drawn in Orthogonal on the left and the same object drawn in a 3D type projection called Isometric on the right. Orthogonal drawings are great for showing details and Isometric drawings are great for showing the overall shape of an object. The Living Toolbox CO 2 Powered Race Car Resource Folio 29

31 The Balsa blank which we are going to use make your racer is shown to the left. We are going to use Orthogonal Projection to draw the CO 2 racer which you have designed, however, as there is not much detail on the front or back of the car to draw at this stage, so we will begin by drawing the top and side views. Figure: (REA, 2012) The first thing that we must do is position the views correctly. This involves ensuring that the top view is positioned directly above the front view. The top view shows what the Racer would look like when viewed from above. The front view shows what the CO 2 racer would look like when viewed from the side. Below is an example of a F1inSchools CO 2 racer drawn in orthogonal projection. Figure: (REA, 2012) In the F1inschools project, the actual drawings that you will use will be generated by the CAD package that you use to draw the CO 2 racer. Options for this program are: CATIA, CREO, GOOGLE SKETCH UP Etc. However, to truly understand orthogonal drawing it is best to actually complete some yourself. In our case we can use the sketches that you have created and turn them into accurate top front and side views to complement your CAD Drawings. We can use the outer shape or shell of our balsa block as the basis for our orthogonal drawings. As you begin to draw your racer, you will note how much easier and quicker it is to draw your racer when your views are aligned as you can project from one view to the next. Here are some useful videos to watch that will assist you do this Now that you understand how to complete orthogonal drawings you may use instruments to construct an orthogonal drawing of your F1 Racer, based around the standard balsa blank. The Living Toolbox CO 2 Powered Race Car Resource Folio 30

32 The process of sketching does not come naturally to everyone. Some people can look at an object and see it as a sketch in their mind and then draw it on paper. For the rest of us, it is a learned process. Here are some basic steps to learn how to sketch an F1inSchools style racer. Figure: (REA, 2012) General Tip Look at sketches of similar objects to determine how they were drawn. Then, use the same shapes, line thicknesses and shading to create your own (Holden, 2011). Side View Sketch Tips Firstly you need to start with an outline of the balsa block for which your F1inSchools car will need to be built. You can estimate the proportions and draw with a rule if you like. Add the wheels next in the approximate location. Remember that the wheels will be outside the confines of the balsa block. Note that the position of the cartridge hole has also been added. This is to help ensure that your F1inSchools racer design does not interfere with the cartridge hole. Now add more detail lines to define the outline of your racers shape. Now add more internal detail to your design to better define internal shapes and design ideas. Finally use an eraser to removal any lines which are not necessary. At this point it is also advisable to go over your outlines with a fine liner pen to better define lines and to assist definition if you wish to scan any designs latter. Sometimes the use of a grid can assist with the sketching process and can give a better understanding of proportions, scale, etc. The Living Toolbox CO 2 Powered Race Car Resource Folio 31

33 In order to continue with the design, testing and manufacturing of the CO 2 racer, a 3D CAD drawing of the racer needs to be completed. The following drawings will be need to be completed. 1. Drawing of assembled car ready to be coded for manufacturing. 2. Orthogonal drawings of each side of car. 3. Detail drawings of features where required. Eg. Wheels 4. Completed car on a turntable, realistically rendered including shadows, just as the finished car will look. Some teams will require more drawings depending on their design and expertise. Computer-aided manufacturing (CAM) is the use of computer software to control machine tools and related machinery in the manufacturing of workpieces. After you have drawn your F1inSchools car in a CAD program you need to code your car using QuickCAM Pro software. Once coded, your car can be manufactured using a Denford CNC router. Figures: (DENFORD, 2012) Finishing Once your F1inSchools car has been cut out using the Denford router it needs to be smoothed by sanding. Take your time during the finishing process. Not only will this make your car more attractive but it can also make it go faster. A smoothly finished surface is more aerodynamically efficient than a rough one. Before painting your car, sand it first with a medium grit garnet paper to smooth rough surfaces. Then sand with a fine grit garnet paper to remove small scratches and marks. Often, the amount of time spent sanding will determine the quality of the paint job. So take your time and try to remove all imperfections. For an ultra-smooth surface, apply a coat of sanding sealer or spray putty before further sanding (PITSCO, 2012). The Living Toolbox CO 2 Powered Race Car Resource Folio 32

34 Painting Figure: (Pitsco, 2012) Insert a piece of dowel rod into the cartridge hole of the dragster body. You can either hold the end of the dowel or clamp it in a vice whist painting. A painting stand is available from the Pitsco website for this purpose. If you are spray painting, spray light coats and wait a few minutes between coats to let the paint dry. Lightly sand between coats with wet and dry 400 grit paper. After the final coat has dried, you can brush on fine detail work like pinstripes or add decals for a realistic race car appearance. Adding a final layer of clear coat or lacquer over the paint can provide a nice, glossy finish as well as protection for decals and detail work (PITSCO, 2012). Assembling Figure: (Pitsco, 2012) Place wheels and axles onto the F1inSchools car and add eye screws on the base. Testing This is an important step that should not be overlooked. At this point in the process, you can make slight changes to your car to improve its performance. Testing will tell you just how to change you F1inSchools car. You should test your design for following specifications, weight, aerodynamic efficiency and rolling resistance. Periodically measure and weight your car to make sure it s with specifications! Figure: (Pitsco, 2012) You can weight your car with or without wheels installed, however, four wheels, two axles, two screw eyes, and washers must be added to the overall weight specification. Hint: Adding several coats of paint during the finishing process can add a few grams of weight. If your car weighs much more than the minimum specification, try carving or shaping the car body some more to make it lighter. At various stages of the production process, you can test the aerodynamic properties of the evolving F1inSchools car. The Pitsco Scout wind tunnel will measure the frontal drag and lift on the car body. The FLO wind tunnel available from REA in Australia uses a fog vapour that passes over the car body so you can actually visualise the airflow over your race car (PITSCO, 2012). Figure: (Pitsco, 2012) The Living Toolbox CO 2 Powered Race Car Resource Folio 33

35 Once you have completed this task you might like to consider forming a team and entering the international F1inSchools technology challenge. Students not only learn about but also experience engineering as they design, build, and race their CO 2 powered cars. The main difference between what you have done for this task and the completion is specifications and tolerances change each year for the F1inSchools competition. Specifications and Tolerances Students designing and building CO 2 race cars experience the same challenge faced by many engineers: working with specifications and tolerances. Specifications are a detailed set of requirements. Specifications can be measurements, capabilities, or limitations on a CO 2 cars, size, weight, or functionality. Often a designer is handed a set of specifications before he or she begins a project. The CO 2 cars must be able to do this, go this fast, and be roughly this size. The challenge for the designer is to be creative and develop an innovative, effective solution while working within the established parameters. In the F1inScools innovation challenge a new set of specifications and rules are set it each year. For the F1inSchools competition details of rules and specifications can be obtained from the REA web site Tolerances are usually dictated to control the quality of a product. No two parts are ever made exactly the same. There are minute differences (perhaps a few ten-thousandths of a millimetre) in the measurements of two similar parts. Some variance in measurement is considered acceptable, as long as it s not too great. A tolerance is an acceptable variance from the specified measurement (REA, 2012). Using the race car project steps shown on the next page, as a guide and now that you are familiar with some of the factors that influence racer design, you can begin to design your own racer based around the principles that you have learnt. Firstly, the design process for a CO 2 race car is linear, that is, each step is followed in succession. However, as there are a million different ways to build things, the designer is quite often forced to consider other components which relate to the area being designed. Secondly, the design process demands some estimation and compromise. Juggling is what it's all about. This is where you want specifications ready to assist you in putting the pieces together. In our case the rules and regulations of the F1inSchools competition dictates the parameters that our racers must be designed to meet (REA, 2012). Figure: (REA, 2012) The Living Toolbox CO 2 Powered Race Car Resource Folio 34

36 The chart below illustrates the major steps in designing and eventually manufacturing a car. (See explanations below) The design steps are discussed in more detail below. RESEARCH EXISTING F1 RACERS F1 RULES AND REGULATIONS PRELIMINARY DESIGN SKETCHES FINAL DESIGN TESTING ( Computer Aided) FINAL DESIGN on Paper and then on CAD Package DEVELOPMENT OF PRELIMINARY DESIGN SKETCHES FINAL DESIGN REFINEMENT AND COMPLETION MANUFACTURING OF RACER PRELIMINARY TESTING COMPETITION RACER ANALYSIS AND REFINEMENT The Living Toolbox CO 2 Powered Race Car Resource Folio 35

37 1. Research of Existing F1 Racers is there to put a reality check into place before any work is done. It is important to understand what existing F1 racers look like, their problems, prior to spending time designing your racer. Figures: (PITSCO, 2002) 2. F1 in Schools Rules and Regulations is the step where you must go out research the rules and regulation that the completion runs by in order to design a car which meets all of the criteria. Failure to do this at this point may lead to extra work at later stages in redesigning. 3. Preliminary Design Sketches is where you translate the pictures you have in your head of the basic concepts, shapes and ideas of your Racer and note them down. These may be simple thumbnail size sketches of concepts that you are considering. 4. Development of Preliminary Design Sketches is the next step. When you study your preliminary designs, you should evaluate them for acceptability in terms of meeting all of the rules and regulations. If there are conflicts in the design, or areas that can be improved, make the change, but keep a baseline copy to go back to if the idea didn't work. 5. Final Design is not really the final design. Actually, it is the complete design. This is where you pull out the drafting paper or start your CAD package The goal of this design is to assemble the entirety of the parts you have in the design into a car. Figure: (REA, 2012) The Living Toolbox CO 2 Powered Race Car Resource Folio 36

38 6. Final Design Testing can be done if you have the right software. These tools consist of Finite Element Analysis and Fluid Dynamics simulations to test aerodynamics. 7. Final Design Refinement and Completion will consist of small changes that will have become apparent once the racer has been tested in the virtual programs. If it's not clear, then you need to revisit your final design stage. More often than not, this will mean going back to research some more to find solutions to problems or shortcomings. Figure: (REA, 2012) 8. Manufacturing of the Racer is the point at which the design of the racer which has been developed is converted to a computer code which then allows the Computer Aided Manufacturing System to read the design and actually machine the racer. Figure: (REA, 2012) Preliminary Testing can commence once the racer has been manufactured, finished and assembled with wheels axles etc. The racer can then be further tested in a series of apparatus including smoke tunnels, scales, race tracks, etc and further variables affecting performance evaluated. E.g. Type of wheels, axles etc. Figure: (REA, 2012) 9. Competition is the part of the process which we all love. At this stage the work that you have done is finally put to the test and your racer is fired along the track against others to see who has the fastest design. Figure: (REA, 2012) The Living Toolbox CO 2 Powered Race Car Resource Folio 37

39 The following are steps in the development of a professional F1inSchools CO 2 car design folio Title Page and 3D Rendering About Us/The Team Project Management & Communication Graphic Design/Promotion/Marketing/Team Identity Collaboration/Mentoring/Sponsorship Research/Theory Design Concepts Development & Testing Materials & Manufacture Technical Drawings The Living Toolbox CO 2 Powered Race Car Resource Folio 38

40 [1] REA (2012). "Re-Engineering Australia Foundation." < [2] LAVC (2012). "STEM." < [3] PITSCO (2002). "The Science of Speed." < [4] Creationtips (2009). "Robert Boyle Biography." < [5] Benson, T. (2007). "Animated Boyle's Law." < 12/airplane/aboyle.html>. [6] uoregon (2012). "Chapter 14: Gases and Plasmas." < [7] old-picture.com ( ). "Wright Brothers Airplane." < [8] Cislunar ( ). "The Wind Tunnel." < [9] OTEN (2002). "Aeronautical Engineering " Distance Education, OTEN, Dubbo. [10] Cetin (2005). "Zodiac CH 640 Design and Construction." < (7/8/2012, 2012). [11] Illusionist (2011). "Introduction to Aeroplane." < [12] Collier, J. (1904). "Osborne Reynolds Scientist, Engineer and Pioneer." < [13] Barker (2012). "Slow is Faster." < [14] DENFORD (2012). "DENFORD." < [15] Ryan, E.,. Ryan, M,. Withero, D,. Bresnan,. D. (2012). "Team Blink." < [16] Flightlearnings (2012). "Lift and Basic Aerodynamics." < (7/8/2012, 2012). [17] Adamone (2012). "Aerodynamics." < [18] Scott, J. (2005). "Golf Ball Dimples & Drag." < (7/8/2012, 2012). [19] Cortana (2006). "Description of Drag." < [20] Edmont (2009). "Boat sailing the Lyse fjord in Norway." < [21] NASA (1990). "Wake Vortex Study." < [22] Aquaphoenix (2012). "Segway Human Transporter in Simplified Mechanics." < (19/08/2012, 2012). [23] Magda, M. (2006). [24] MSulka (2007). "Technical Feature: In Depth of Preparing a Formula One Car for Monza." PaddockTalk, < [25] Holden, B. (2011). The Engineered Dragster: Design Basics, Pitsco. [26] Glimmerveen, J. (2009). "Formula One Suspension Set-Up for the Rain." Auto Racing Suite101, < [27] Holden, B. (2011). The Engineered Dragster: Sketching, Drafting, and Prototyping, Pitsco. [28] PITSCO (2012). The Race Car Book, Pittsburg. [29] Pitsco (2012). "Pitsco Education Store." < (19/08/2012, 2012). The Living Toolbox CO 2 Powered Race Car Resource Folio 39