RIT Formula SAE Senior Design

Transcription

1 RIT Formula SAE Senior Design

2 Agenda Project Description Work Breakdown Customer Needs Customer Specifications Current/Previous System Design Proposed Design #1 Proposed Design #2 Testing Plans Concept Selection Risk Assessment

3 Project Introduction As each competition passes, fuel efficiency and technical superiority becomes much more prevalent in competition scoring. To advance the RIT Formula SAE Racing Team in the engine subsystem, the variable intake system will prove to be innovative and technically competitive. Problem Statement: This senior design project will develop a variable intake system for the Formula SAE race car that will allow for increased fuel efficiency, design advancements and a greener methodology to produce more engine power.

4 Project Introduction Project Scope: 1. Measure the fuel efficiency of the engine 2. Improve power and torque 3. Packaging the system with simplicity to allow for ease of installation and maintenance 4. Design and build for the non-professional, weekend and competition market

5 Work Breakdown FSAE Intake System Project Manager Test Engineer Integration Engineer Scheduling (Kursten) Documentation (Kursten) Meeting Planning (Kursten) Final Intake Design (Dave) Design Engineer Fluids/CFD Analysis (Dave) Design all Test Equipment (Matt) Testing and Tuning (Matt and Kursten) Testing Schedule (Matt) Programming Motec (Dan) Controls Engineer Integrating intake into engine (Tom) Data Analysis of Motec Output (Dan) Wiring (Tom)

6 Customer Needs

7 Specifications

8 Previous Intake Designs F17 Intake Results show that the F17 intake did not have a favorable distribution of air, as cylinder #1 is shown to receive 17% of the total ingested air, where cylinder #4 receives 30%. Cylinder #3 and #4 both received approximately 26%.

9 Proposed Design #1: Infinitely Variable The variable length runner concept has been proven and implemented in both motorsport and production vehicles. The first publicized application was on the Mazda 787B LeMans race car in The 2.6 liter rotary engine was outfitted with continuously variable intake runners that were actuated with a cable and pulley system. The Mazda team found an increase in peak torque, as well as a broadened torque curve by implementing the system.

10 Proposed Design #1: Infinitely Variable Necessary electrical components for packaging and integration into existing engine IR Distance Sensor -1.5 to 11.5 Detection Range -Analog Output Voltage -Compact and Low Weight Design Linear Actuator -2 Amp Maximum Current Draw at 12V DC inches/sec at 8 pounds of force -Integrated Microcontroller

11 Proposed Design #2: 2 Position Long Mode Low RPM Variable length intake runners have also been implemented in production motorcycles, namely the Aprilia RSV4 Factory, and the Yamaha R1 and R6. All three use a two position runner, in which a section at the end of the runner is disconnected at a specific RPM, creating a shorter runner. Both Yamaha and Aprilia report that the variable runner results in a broader power band. Short Mode High RPM

12 Proposed Design #2: 2 Position Necessary electrical components for packaging and integration into existing engine Solenoid Valve -Compact Design -Fast Response Time (15ms) -Proven Reliability Pneumatic Cylinder -2 Cylinder with.5 Stroke -Internal Spring Return Air Pressure Regulator -30 PSI Adjustable Regulation -Lightweight design

13 Packaging: The geometry of the chassis, as well as the governing rulebook, defines the packaging area for the intake system. The intake must lie within the area outlined below. The two different designs (infinitely variable, and two position) lend themselves to different overall layouts. The infinitely variable, tube-in-tube design requires that the static runner has a straight section leading into the plenum of a length minimally equal to the length of actuation. For example, if the operating range were to be 7 to 11 inches, a straight section at least 4 inches would be needed to accept the sliding runner s length. Design Concerns

14 Sub-System Breakdown Mechanical System Testing The mechanical system is comprised of the sliding interface that allows the change in runner length and the plenum that the runners interact with. This system must allow for the desired change in length, not leak, maintain desired plenum volume, and comply with the FSAE rulebook. Actuation System The actuation system will move the mechanical system based on inputs from the control system. Actuation speed is critical for this application as transient times must be kept under 100ms. This system must also be able to gauge the system s location. Control System The controls for this system will be fully integrated into the engine control unit (ECU) for the vehicle. Using inputs such as RPM, throttle position, manifold pressure and current runner length the control system will output a desired runner length to be achieved by the actuation system. Supporting Systems The variable intake will interface with the engine on one end and a throttle/ restrictor assembly on the other. Sufficient information on the flow characteristics of the throttle/ restrictor assembly will be needed to design and tune this system. The electrical requirements of the actuation system will be provided by the vehicle s stator. There is a limited amount of power available from this system, which must be taken into account.

15 Testing Equipment Test Equipment available Machine shop equipment DC Dynamometer Chassis Dynamometer Honda CBR 600 test engine RIT FSAE race car Electronic test equipment Computers Test Equipment needed but not available Flow bench Vehicle based data acquisition system (DAQ)

16 Necessary electrical components for packaging and integration into existing engine Testing Equipment Engine Combustion Pressure Sensor In-Line Charge Converter Coaxial Cable Incremental Encoder

17 Using the previously design intake system for F17, modification were made in order to test at various runner lengths on the dyno Testing - Prototype

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20 Concept Selection

21 Risk Assessment Type Risk Effect Cause Likelihood Severity I.S. Action to Minimize Risk Owner PM/ PM Response time is not fast enough to engage length A change in runner length results in a change in plenum volume that has unknown results regarding power and functionality Servomotor needed are not available Not start testing on time Pressure Sensors not compatible with engine Pressure Sensors not compatible with dyno Not have enough $ to sponsor project from ME Dept. The dyno facility is not up and running No available materials The intake system packaging will not fit the FSAE envelope regulation Wiring available does not work Not capable of measuring fuel economy Intake system will not be accurate, possibly not effective Unknown and unaccountable variables in the design and testing phase Motech cannot program to the level necessary, engine cannot meet the specified load timing Not knowing enough about engine characteristics for different volume changes Not able to run intake system No other servos are available Delay data gathering to make specs Will not have a method to tune intake system Will not have a method to tune intake system Not be able to purchase the materials needed to build the system Delays preliminary testing and data gathering Not able to build prototype or completed intake system The intake system cannot be used in competition Cannot wire the intake system to the motech computer system Unable to measure a deliverable Dyno facility not working Fittings are not compatible Fittings are not compatible Costs are out of the range ME Dept is willing to give Spec the response time correctly that can be found via calculations and testing and researching in addition to consulting with our technical advisor Research and plan 2-3 weeks before servo will be needed Work with John Scanlon to schedule testing time Design fittings that will work with the already purchased sensors Design fittings that will work with the already purchased sensors Tom/Dan Dave Donohue Kursten O'Neill and Matt Smith Matt Smith Tom/Dan Tom/Dan Look to minimize cost in all areas All The dyno breaks Work with John Scanlon Matt Smith Not planning far enough in ahead on specs in order to purchase the material ahead of time Design constraints will not allow system to stay within envelope borders Work with FSAE and ME Dept to ensure that we have enough materials Design for envelope borders under a given factor of safety Kursten O'Neill Dave Donohue Old/unreliable wire Check all wires before assembly Tom/Dan We do not have the equipment or capabilities to measure Machined runner's not in spec Not compatible with intake system Machined incorrectly Not being able to use F17's intake system for testing The manufacturing of the system will be outside the capabilities of the team members Car not running We would have to make our own testing intake system Unable to machine intake system Not able to test the intake system on the car Needed for FSAE testing and tuning on other cars Design constraints will not allow for a simplified machining technique Running late on assembly in FSAE Brainstorm and plan for the most feasible method to measure Take precautions when machining all components Talk with Project Manager and Chief Engineer before it is needed Design within machine shop capabilities Work with FSAE to ensure that the car is on schedule Matt Smith Matt Smith Matt Smith and Dave Donohue Dave Donohue Matt Smith and Dave Donohue

22 Questions?