docFinal presentation1104-08
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Final presentation1104-08
ME1104-08 Elliot Rose Scott Hamilton Conrad Meekhof Faculty Advisor: Dr. Claudia Fajardo Industrial Sponsor: DENSO North America Foundation Project Goals • Design a forced-air induction system for a Suzuki RM-Z450 for use in the WMU Formula race car • Meet or exceed previous engine power to weight ratio • Increase fuel efficiency • Increase volumetric efficiency and engine torque Why? • Increase in points awarded for fuel economy from 5 to10% of total competition points • Accomplished using engine downsizing • Power output decreases by engine downsizing Method • Design was completed using parametric solid modeling, one-dimensional engine simulation software and experimental testing. Forced induction system selection Engine system modeling (Ricardo Wave Software) Engine model validation • Restrictor • Analytical peak pressure calculation (MathCAD) Sensitivity Study Design Iterations Cam Profile Design Design Results Conclusions, Recommendation and Future Work http://www.wmich.edu/engineer/images/splash/2-9.jpg Current Engine • Suzuki GSX-R600 Four-cylinder, 600cc displacement 4 valves per cylinder Weight: 125 lbs Port fuel injected Vehicle power to weight ratio: 0.14 Proposed Engine • Suzuki RM-Z450 Single-cylinder, 450cc displacement 4 valves per cylinder Weight: 75 lbs Gas direct injection redesign Vehicle power to weight ratio: 0.11 Eaton R410 Roots Supercharger • Weight: 15 lbs • Parasitic loss: 6.0 HP– 8.0 HP • Effect on throttle response • Designed for 500cc – 1400cc displacement engines Honeywell GT12 Turbocharger • Weight: 8.8 lbs • Parasitic Loss: 0 HP • No effect on throttle response • Designed for 500cc – 1,200cc displacement engines Honeywell GT15VNT Turbocharger • Weight: 10 lbs • Parasitic Loss: 0 HP • Maximum exhaust input temperature of 825 °C • Variable vane turbine • Designed for 1000cc – 1600cc displacement engines Supercharger http://www.eaton.com/ecm/groups/public/@pub/@eaton/@per/ documents/content/ct_126004.jpg Turbocharger http://www51.honeywell.com/honeywell/news-events/graphic-library-n3/ transport-systems/images/3.5.3.4.1_gt12_turbo_charger_2.jpg Ricardo Wave (1-D engine simulation software) Restrictor implementation (FSAE rules) Turbocharger implementation Camshaft measurement • Design Variables Overlap Lift Duration Mathematical model Turbocharger Camshaft profiles Restrictor Validated Base Model Turbocharged Engine Model with Restrictor Restrictor verification • Flow bench Stock cam profiles • Directly correlate to the cam profiles in the validated engine model • Less than 14% error 150 0.40 Valve Lift (in) Volumetric flow rate (CFM) 100 50 0 0 0.1 0.2 0.3 0.4 0.5 Pressure Drop (psi) Exparimental Ricardo 0.6 0.30 0.20 0.10 0.00 -400 -200 0 200 Crank Angle (Degrees from TDC) Intake Exhaust 400 Design variables • • 8 variables identified This would result in greater than 1,000 iterations Identify critical components Component variation • • • Packaging 6 pipe lengths varied from 2 inches to 8 inches 2 plenum volumes varied from 0.5 L to 4 L Power at 7000 RPM Varied Component Min (hp) Max (hp) Percent difference Restrictor to compressor Runner 26.1 26.3 0.7 Compressor to Plenum Runner 26.1 26.3 0.9 Intake Plenum 26.0 27.6 6 Plenum to cylinder Runner 26.9 30.2 10.8 Cylinder to plenum Runner 24.4 29.4 16.9 Exhaust Plenum 18.5 31.3 40.8 Plenum to turbine Runner 26.0 26.3 1.2 Turbine to muffler Runner 25.8 26.2 1.4 Limits set by packaging constraints Number of iterations: 290 Analyzed according to design criteria Turbocharged restricted engine model • Marginal performance improvements at engine speeds below 8,000 RPM over the stock restricted engine model • Greatest performance improvements located above 8,000 RPM Power (hp) 15% improvement at 8,000 RPM 60% improvement at 12,000 RPM 80 70 60 50 40 30 20 10 0 3000 Component 5000 7000 9000 Engine Speed (RPM) Initial Redesign Restricted 11000 Final Size Restrictor to compressor runner 2 in Compressor to plenum runner 3 in Intake plenum 2 L Plenum to cylinder runner 5 in Cylinder to plenum runner 5 in Exhaust plenum 5 L Plenum to turbine runner 18 in Turbine to muffler runner 3.5 in 40 35 30 25 20 15 10 5 0 3000 Valve Lift (in) Problem • Excessive exhaust pressure causing backflow Objective • Reduce exhaust backflow • Increase volumetric efficiency Profile redesign • Intake valve opening shifted 65 crank angles • Reduced valve overlap by 66% Pressure (psi) 5000 7000 9000 11000 Engine Speed (RPM) Intake Exhaust 0.40 0.35 0.30 0.25 0.20 0.15 0.10 0.05 0.00 -400 -200 0 200 400 Crank Angle (Degree from TDC) Exhaust Intake Intake Redesign Performance results • Improved performance throughout the engine speed range Increased brake power by ~30% 80 1.6 70 1.4 Volumetric Efficiency Brake Power (hp) Increased volumetric efficiency by ~19% to 56% Lowered exhaust back flow by ~ 50% 60 50 40 30 20 10 0 3000 5000 7000 9000 11000 Engine Speed (RPM) Stock Camshafts Redesigned Camshafts 1.2 1 0.8 0.6 0.4 0.2 0 3000 5000 7000 9000 11000 Engine Speed (RPM) Stock Camshafts Redesigned Camshaft Goals • Recover power to weight ratio lost when down sizing • Increase fuel efficiency Power increase • Final design increased peak power by 41% over restricted stock engine Brake Power (hp) 80 70 60 50 40 30 20 10 0 3000 Power to weight ratio Stock Restricted Fuel efficiency • Marginally decreased over the engine operating range • Fuel efficiency gains from directinjection design will compensate for this reduction Brake Specific Fuel Consumption (kg/kW/hr) 7000 9000 11000 Engine Speed (RPM) • Increased by 35% over restricted stock engine • Increased 21% over the GSX-R 600 5000 Final Design 0.35 0.325 0.3 0.275 0.25 0.225 0.2 3000 5000 7000 9000 11000 Engine Speed (RPM) Stock Restricted Final Design Goals • Increase low end torque • Increase volumetric efficiency Torque increase • 35% over stock restricted Brake Torque (Ft-lbs) engine Volumetric efficiency • Stock restricted: 87% at 8,000 RPM • Final design: 144% at 9,000 RPM 5000 7000 9000 Engine Speed (RPM) Stock Restricted 11000 Final Design 1.6 Volumetric Efficiency 45 40 35 30 25 20 15 10 5 0 3000 1.4 1.2 1 0.8 0.6 0.4 0.2 0 3000 5000 7000 9000 11000 Engine Speed (RPM) Stock Restricted Final Design Implement forced air induction system featuring: • Honeywell Garrett GT12 Turbocharger • Plenum volume Intake: 2 L Exhaust: 5 L • Critical runner lengths Plenum to intake: 5 in. Exhaust to plenum: 5 in. • Cam change Delay intake opening 65 crank angles 66% reduced overlap Gear Picture Courtesy of Honeywell vehicle drivetrain to best utilize power produced. Experimental validation of simulation model • Physical system build Further refinement of engine packaging • Exploration of plenum geometries Ricardo VECTIS • 3-D computational fluid dynamics software • Intake and exhaust system flow characteristics WMU Mechanical & Aeronautical Engineering Department Dr. Claudia Fajardo Dr. Richard Hathaway Michael Nienhuis DENSO Garrett by Honeywell • • Nathan Theiss Eaton Zach Tuyls Ricardo PLC Benchmarking • Intercooling was not used in successful designs Plenum Intake Temperature (°F) • Allows time for intake air to cool 300 250 200 150 100 50 0 3000 5000 7000 9000 Engine Speed (RPM) Final Design Stock Restricted 11000 Dual Cycle • Partial heat addition at constant volume • Partial heat addition at constant pressure Results • 33% error in peak pressures between mathematical model and simulation Mathematical model does not account for heat loss. Constant Pressure Constant Volume Compression Expansion Waste gate controls knock by limiting intake pressure • Exhaust gas bypasses turbine Knock was not detected in any simulation which included airflow restriction Boost ratio in simulations was 1.8 • Turbo remained in most efficient region
