FORMULA SAE ENGINE INTERNALS GROUP. Emerson Hawkins, Whitney Hurlbut, Kirk Fraser, Saad Mohamed and Greg Fitzpatrick

Transcription

1 FORMULA SAE ENGINE INTERNALS GROUP Emerson Hawkins, Whitney Hurlbut, Kirk Fraser, Saad Mohamed and Greg Fitzpatrick

2 PRESENTATION OVERVIEW Plan FSAE Engine Internals Group Fall Presentation 2

3 PRESENTATION OVERVIEW Plan FSAE Engine Internals Group Fall Presentation 3

4 PRESENTATION OVERVIEW Plan Gearbox Crankshaft Flywheel FSAE Engine Internals Group Fall Presentation 4

5 PRESENTATION OVERVIEW Plan DAQ Vibration Rotational Mass FSAE Engine Internals Group Fall Presentation 5

6 PRESENTATION OVERVIEW Plan FSAE Engine Internals Group Fall Presentation 6

7 PRESENTATION OVERVIEW Plan FSAE Engine Internals Group Fall Presentation 7

8 PRESENTATION OVERVIEW Plan FSAE Engine Internals Group Fall Presentation 8

9 PROJECT OVERVIEW AND OUTCOMES Formula SAE Students develop and market a low-production, open-wheeled racecar for weekend autocross racers Overview and Plan FSAE Engine Internals Group Fall Presentation 9

10 PROJECT OVERVIEW AND OUTCOMES Honda CBR 600RR Engine with a 20 mm intake restriction: Power: RPM Torque: RPM Top speed: 140 km/h Overview and Plan FSAE Engine Internals Group Fall Presentation 10

11 Output Torque (Nm) Output Torque (Nm) PROJECT OVERVIEW AND OUTCOMES 350 Torque Curve for Stock Gearbox Ratios Torque Curve for Modified Racing Gearbox Ratios Gear 1 Gear 2 Gear 3 Gear 4 Gear 5 Gear Vehicle Speed (km/h) Vehicle Speed (km/h) Overview and Plan FSAE Engine Internals Group Fall Presentation 11

12 PROJECT OVERVIEW AND OUTCOMES Reduce rotating mass Gearbox Main Shaft Counter Shaft Crankshaft Flywheel Overview and [USA, Motorcycle USA.2005 BMW K1200S Photo Gallery. n.d. Plan FSAE Engine Internals Group Fall Presentation 12

13 PROJECT OVERVIEW AND OUTCOMES Improve Overall Performance Acceleration Torque Power Throttle Response Weight Reduction Drivability Overview and Plan FSAE Engine Internals Group Fall Presentation 13

14 DESIGN REQUIREMENTS Increase torque by 5% from baseline of 53.7 Nm. Increase overall horsepower by 5% from baseline of 70.5 hp. Increase throttle response by 10% from baseline of seconds. Decrease 75m acceleration time by 5% from baseline of 4.797s. Decrease internal rotating mass by 5% from baseline of 17.5 kg Plan FSAE Engine Internals Group Fall Presentation 14

15 Overall Placing PROJECT OVERVIEW AND OUTCOMES Historical and Predicated Placing 0 Competition Year st 40 40th th th 90 93rd 100 Plan FSAE Engine Internals Group Fall Presentation 15

16 Total Points PROJECT OVERVIEW AND OUTCOMES 500 Historical and Predicted Point Distribution Efficiency Endurance Autocross Skid Pad Acceleration Presentation Cost Competition Year Plan FSAE Engine Internals Group Fall Presentation 16

17 DESIGN ALTERNATIVES Gearbox Alternatives: 1) a Custom Gearbox a) Build it b) Outsource it 2) Modify the Nova Racing Honda CBR 600RR Racing Gearbox a) 6 speed b) 5 speed c) 4 speed 3) Modify the Stock Honda CBR 600RR Gearbox a) 5 speed b) 4 speed Gearbox Crankshaft Flywheel Plan FSAE Engine Internals Group Fall Presentation 17

18 DESIGN ALTERNATIVES Gearbox Crankshaft Flywheel Plan FSAE Engine Internals Group Fall Presentation 18

19 DESIGN ALTERNATIVES Crankshaft Alternatives: 1) Reduce overall mass a) Drill holes throughout b) Reduce outer diameter of lobes c) Reduce thickness of the lobes Gearbox Crankshaft Flywheel Plan FSAE Engine Internals Group Fall Presentation 19

20 DESIGN ALTERNATIVES Flywheel Alternatives: 1) Machine Outer Radius to Reduce Weight 2) Total-Loss System Gearbox Crankshaft Flywheel Plan FSAE Engine Internals Group Fall Presentation 20

21 ENGINEERING ANALYSIS Testing and Data 1. Mass and Dimensions 2. Simulations 3. Dynamometer 4. Test Driving DAQ Rot. Mass Vibration Plan FSAE Engine Internals Group Fall Presentation 21

22 ENGINEERING ANALYSIS Mass Distribution of Rotating Engine Components Counter Shaft 19% Forks R 1% Shift Drum 3% Flywheel 7% Main Shaft 10% Steel Discs 4% Clutch Center 3% Clutch 1% Crankshaft 38% IN Cam EX Cam 6% Piston 6% 2% DAQ Rot. Mass Vibration Plan FSAE Engine Internals Group Fall Presentation 22

23 ENGINEERING ANALYSIS Other 44% Main Shaft Gears (% of shaft) Fifth 13% Third/ Fourth 21% Other 37% Counter Shaft Gears (% of shaft assembly) First 11% Fifth 15% Fourth 6% Second 8% Sixth 14% Second 9% Sixth 15% Third 7% DAQ Rot. Mass Vibration Plan FSAE Engine Internals Group Fall Presentation 23

24 ENGINEERING ANALYSIS Component Dimensions DAQ Rot. Mass Vibration Plan FSAE Engine Internals Group Fall Presentation 24

25 ENGINEERING ANALYSIS Simulations Optimum Lap Load Vehicle Graph Engaged Gears Lap Times DAQ Rot. Mass Vibration Plan FSAE Engine Internals Group Fall Presentation 25

26 ENGINEERING ANALYSIS Optimum Lap Dal FSAE DAQ Rot. Mass Vibration Plan FSAE Engine Internals Group Fall Presentation 26

27 ENGINEERING ANALYSIS Engine Dynamometer Baseline Engine Performance Curves HP Torque DAQ Rot. Mass Vibration Plan FSAE Engine Internals Group Fall Presentation 27

28 ENGINEERING ANALYSIS Dynamic Testing Acceleration runs Stop watch Static Testing Throttle Response MoTeC i2 Standard DAQ Rot. Mass Vibration Plan FSAE Engine Internals Group Fall Presentation 28

29 ENGINEERING ANALYSIS Gear Stock Ratio % Drop Nova Racing % Drop : : :1 27.3% 2.133:1 20.0% :1 16.8% 1.833:1 14.0% :1 12.5% 1.631:1 11.0% :1 10.6% :1 7.5% - - Overall Reduction Gear Ratios 2.286:1 56.3% 1.635:1 38.8% DAQ Rot. Mass Vibration Plan FSAE Engine Internals Group Fall Presentation 29

30 ENGINEERING ANALYSIS Heavy rotating mass slow acceleration Light rotating mass more horsepower DAQ Rot. Mass Vibration Plan FSAE Engine Internals Group Fall Presentation 30

31 ENGINEERING ANALYSIS Moment of Inertia: Stores kinetic energy Resists engine rotation Slows acceleration and throttle response Equivalent Mass: Relates rotating mass to static mass on car DAQ Rot. Mass Vibration Plan FSAE Engine Internals Group Fall Presentation 31

32 ENGINEERING ANALYSIS Power : Dependant on engine RPM Smaller MOI requires less power for acceleration Smaller power requirement = faster acceleration DAQ Rot. Mass Vibration Plan FSAE Engine Internals Group Fall Presentation 32

33 ENGINEERING ANALYSIS Original parameters Crankshaft Flywheel Mass 8.31 kg 1.51 kg MOI 9.12E-2 kgm E-2 kgm 2 Equivalent mass kg 9.48 kg Rotational Power req W W After modifications Crankshaft Flywheel Mass Reduction 3.3% 10.7% MOI reduction 9.7% 16.4% Equivalent mass reduction 3.3% 10.7% Power req. decrease 9.7% 16.4% DAQ Rot. Mass Vibration Plan FSAE Engine Internals Group Fall Presentation 33

34 ENGINEERING ANALYSIS Vibration: Engine is constantly operating at high speed reciprocating motion. Vibration is inevitable. Minimizing vibration improves drivability. Crankshaft and Flywheel requires careful machining. DAQ Rot. Mass Vibration Plan FSAE Engine Internals Group Fall Presentation 34

35 PROPOSED DESIGN Flywheel Total Loss System Reduce outer diameter Crankshaft Drill holes Knife edge lobes Reduce counterweight radius Gearbox and build custom Stock Honda, gears 5 & 6 removed Nova Racing, gears 5 & 6 removed Plan FSAE Engine Internals Group Fall Presentation 35

36 BUDGET Item Description: Quantity: Cost: Total (CAD): Nova Racing CBR 600RR Racing Gearbox $ Nova Automotive Crank Balancing 1 $ $ Donated Royal Purple Oil 4 $ $ - Machine Crankshaft at Dalhousie 1 $ - $ - Machine Flywheel at Dalhousie 1 $ - $ - Safety Supplies (Cones and Caution Tape) 1 $ $ Gasket Maker 1 $ $ Assembly Lube 1 $ $ Fasteners 8 $ $ Total (CAD): $ 1, Plan FSAE Engine Internals Group Fall Presentation 36

37 PROJECT PLAN Plan FSAE Engine Internals Group Fall Presentation 37

38 THANK YOU FOR YOUR TIME. QUESTIONS?