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Design Team # 3 Shell Eco Marathon ( Super-mileage Car). Members: Hussain Abdellatif Sohaib Syed Alam Julius Mantolino Adam Procter Supervisor: Dr. Alex Kalamkarov. Outline. Background Scope Design Requirements The Design Current Project Status Future Considerations
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Design Team # 3Shell Eco Marathon (Super-mileage Car) Members: HussainAbdellatif Sohaib Syed Alam Julius Mantolino Adam Procter Supervisor: Dr. Alex Kalamkarov
Outline • Background • Scope • Design Requirements • The Design • Current Project Status • Future Considerations • Design Requirements Check • Budget • Acknowledgements 2
Background • Americas Shell Eco-Marathon Competition not to go fast but to use least amount of fuel • Houston, Texas – (March 29-April 1 2012) • 2009 Dalhousie Team - 12th Place (819mpg) • Core Super mileage Team with 4 volunteers • Cover • Steering • Driver 3
Design Requirements • Ultimate Goal: Achieve ≥ 900 mpg • Qualify/Compete for Shell Eco Marathon: • Geometric Limitations • 4 stroke IC Gasoline Engine • Increased Fuel Efficiency • Lighter Powertrain • Lighter Chassis • Lighter & More Efficient Wheels 4
The Design – Our Scope • Engine • Fuel Injection System • Powertrain • Transmission • Bearings • Clutch • Chassis • Wheels 5
The Design -Challenge • Rolling Resistance • Reduction in weight • More efficient wheels • Aerodynamics • Reduction in frontal area 6
Engine • Direct Fuel Consumption • Options Considered: • Old 35cc Honda • Old 50cc XF Yamaha • New 35cc Robin Subaru Honda 35cc [1] Robin Subaru 35cc [2] 50cc XF Yamaha 7
Engine - Selection 8
Engine Modifications -Electric Starter • One-way Needle Bearing • Reused electric motor from Yamaha • Gear reduction 9
Engine Modifications -Muffler Requirement: Max. Noise Level <90 dB • Stock Muffler: • Lower Efficiency • Glass Pack Muffler: • Perforated Design • Packing diffuses sound • Less restriction Glass Pack Muffler [4] 10
Fuel Delivery System • Possible fuel delivery methods: • Carbureted • Port Fuel Injection • Direct Injection • Direct Injection is not Viable: • Requires mechanical fuel pump (competition rules) • Complex 11
Fuel Delivery System -Selection 12
Fuel Delivery System -Electronic Fuel Injection • Replace carburetor • Conversion kit purchased from Ecotron: • Key components: • Oxygen (O2) Sensor • Fuel Injector • Programmable Engine Control Unit (ECU) • Fuel Pressurization System • Throttle Body 13
Sensors – Input Controlled Output Throttle Position Engine Control Unit (ECU) Inlet Air Pressure Inlet Air Temp. Programmable Control Parameters Engine Kill Switch Fuel Injector Crankshaft Position Exhaust Temp. Control parameters as required Exhaust O2 Fuel Delivery System -Electronic Fuel Injection Spark Timing 14
Fuel Delivery System -Pressurization Fuel Pressurization System [5] 15
Powertrain • Transmits power from engine • Require minimum power losses • Provide sufficient torque • Best Efficiency Point (BEP) ∼ 5000 RPM • Provided by bsfccurve • To be verified with testing • Calculate suitable gear ratio: 16
Powertrain - Transmission 17
Powertrain • Components: • Gear Reduction Method • Two Stages • Bearing • Clutch 18
Powertrain – 1st Stage 19
Powertrain - Overall • Planetary Gearbox for 1st stage • Purchase Neugart PLE60-20 Planetary Gearbox from Wainbee Ltd. • 94% efficient • 20:1 gear ratio • Continuous torque 44 N.m. • Roller Chain and Sprockets for 2nd stage 20
Powertrain - Overall • Planetary Gearbox for 1st stage • Roller Chain and Sprockets for 2nd stage 21
Powertrain - Bearings 22
Powertrain -Clutch • Centrifugal [7] • Friction Plate [8] 23
Powertrain -Clutch Selection 24
Powertrain -Torque Calculations • Engine is not overloaded 25
Chassis -Selection • Design Requirement: Lighter chassis • Aluminum Alloy 6061-T6 • Yield strength = 275 MPa • Weight estimate entire car (with driver) ~ 90kg • Withstand static load of 700N on roll bar 26
Chassis – Rear Loading Max. Stress: 55 MPa 27
Chassis – Side Loading Max. Stress: 75 MPa 28
Chassis – Pull Loading Max. Stress: 50 MPa 29
Chassis – Push Loading Max. Stress: 43.8 MPa 30
Wheels • 3 wheels: 2 in front, 1 in back • Front Wheel Design • Lighter • No Internal Ratchet • Back Wheel Design • Internal Ratchet • Heavier Back vs Front Wheel Assembly [9] 31
Wheels • 3 wheels: 2 in front, 1 in back 32
Wheels • Incorporate Sprag Clutch in Back Wheel • Disc Brakes: • Reusing from past team • Consistent brake performance • Hubs & Spokes to be purchased 33
Wheels • Past: • Michelin road tires • Selected: • Continental GatorSkin tires • Higher inflation pressure • 150 psi vs. 60 psi • Lower rolling resistance • Flat and puncture resistant • Durable Michelin Tires [10] GatorSkin Tire [11] 34
Wheels 35
Project Status • Purchased: • Robin Subaru 33.5cc engine • Electronic Fuel Injection (EFI) kit • PLE60-20 Planetary Gearbox • Aluminum tubing for chassis • Designed: • Power Train Components • Electric Starter Assembly • Chassis Main Frame Body 36
Design Req. Check Achieved Already • Qualify/Compete for Shell Eco Marathon • Geometric Limitations • 4 stroke IC Gasoline Engine • Lighter Powertrain (Centrifugal) • Lighter Chassis (30% reduction) To Be Achieved: • Increased Fuel Efficiency - to be confirmed with dyno • Lighter & More Efficient Wheels • Achieve ≥ 900 mpg - TBD 37
Future Considerations • Assemble Power Train • Assemble Power Train, Steering & Cover onto Chassis • Purchase Wheels & Wheel Components • Obtain Engine Curves with Dyno: • Carburetor • Fuel Injection • Fine Tune ECU Programmable Parameters • Dyno Vehicle @ Wheels 38
Budget • Engine $425 • Fuel Injection System $586 • Drivetrain & Clutch (estimate) $2000 • Chassis $500 • Wheels $2500 --------------------------------------------- • Total (15% Contingency) ~ $7000 39
Acknowledgments We would like to thank: • Dr. Julio Militzer • Dr. Alex Kalamkarov • Albert Murphy • Mark MacDonald • Angus MacPherson • Peter Jones • Allison Chua, Drew Moores, Ryan Louie & DainisNams 40
Acknowledgements - Sponsors We Thank Our Sponsors 41
References [1] http://robinamerica.com/pspecsheet [2] http://www.baileysonline.com/itemdetail [3] http://www.elsberg-tuning.dk/yamaha.html [4] http://auto.howstuffworks.com/muffler5.htm [5] http://poisson.me.dal.ca/~dp_09_15/docs/Fall%20Build%20Report.pdf [6] http://www.vxb.com/page/bearings/CTGY/CeramicBallBearings [7] http://auto.howstuffworks.com/clutch1.htm [8] http://auto.howstuffworks.com/clutch1.htm [9] http://www.qbike.com/cgi-bin/find.cgi?st=road+wheel [10] http://www.michelin.ca/ [11] http://www.mec.ca/AST/ShopMEC/Cycling/TiresTubesWheels/RoadTires/PRD~5005-157/continental-ultra-gatorskin-700-x-28-wire-tire.jsp 42
Questions ? 43
Back Up Material • Engine Specs • Load Torque Assumptions • Bearings • Bearing, Output Shaft FEMS • Starter Assembly FEM 44
Torque Calculations (1) • [ref] – common CD used in old 90’s cars • - the max. allowed in competition • - frontal area of around (19inx28in) 46
Torque Calculations (3) Clutch “Bites” Slip Period Clutch transmits engine torque • = 48.15 g, • , • , [ref] • [ref] Max. Clutch Torque Engagement speed 48
Bearings 49