Tables - Rochester Institute of Technology
P13222: FSAE Turbocharger IntegrationMSD I: Detailed Design ReviewThursday, November 8th, 20124:00-6:00pmKelly Conference RoomTeam members: Kevin FerraroPhillip VarsAaron LeagueIan McCuneBrian Guenther Tyler PetersonFaculty Guide: Dr. Alan NyePrimary Customer: RIT Formula SAE Racing Team Contents TOC \o "1-3" \h \z \u Tables PAGEREF _Toc340175940 \h 3Figures PAGEREF _Toc340175941 \h 3Table 1: Project Information PAGEREF _Toc340175942 \h 5Project Description PAGEREF _Toc340175943 \h 5Project Background PAGEREF _Toc340175944 \h 5Problem Statement PAGEREF _Toc340175945 \h 5Objectives/Scope PAGEREF _Toc340175946 \h 5Deliverables PAGEREF _Toc340175947 \h 5Expected Project Benefits PAGEREF _Toc340175948 \h 5Core Team Members: PAGEREF _Toc340175949 \h 5Assumptions & Constraints PAGEREF _Toc340175950 \h 5Issues and Risks PAGEREF _Toc340175951 \h 5Customer Needs Review PAGEREF _Toc340175952 \h 6Table 2: Customer Needs PAGEREF _Toc340175953 \h 6Specifications Overview PAGEREF _Toc340175954 \h 7Table 3: Specifications Review PAGEREF _Toc340175955 \h 7Table 4: Specifications, Continued PAGEREF _Toc340175956 \h 8System Architecture PAGEREF _Toc340175957 \h 9Figure 1: Simplified Block Diagram PAGEREF _Toc340175958 \h 9Compliance with Requirements PAGEREF _Toc340175959 \h 10Induction PAGEREF _Toc340175960 \h 10Table 5: Induction System Compliance PAGEREF _Toc340175961 \h 10Throttle/Restrictor PAGEREF _Toc340175962 \h 11Figure 2: Spike Geometry Comparison PAGEREF _Toc340175963 \h 11Figure 3: CFD Analysis of Spike/Restrictor PAGEREF _Toc340175964 \h 12Figure 4: Restrictor Geometry PAGEREF _Toc340175965 \h 12Intercooler PAGEREF _Toc340175966 \h 13Table 6: Intercooler Compliance PAGEREF _Toc340175967 \h 13Turbocharger PAGEREF _Toc340175968 \h 14Table 7: Turbocharger Compliance PAGEREF _Toc340175969 \h 14Figure 5: GT Power Simulation Schematic PAGEREF _Toc340175970 \h 15Figure 6: GT Power, Efficiency Results PAGEREF _Toc340175971 \h 15Exhaust System PAGEREF _Toc340175972 \h 16Figure 7: GT-Power: Power and Efficiency results, Screen shot of header design #2 (green) PAGEREF _Toc340175973 \h 17Boost Control PAGEREF _Toc340175974 \h 17Table 8:Boost Control System Compliance PAGEREF _Toc340175975 \h 18Figure 8: Boost Control Block Diagram PAGEREF _Toc340175976 \h 19Figure 7: Solenoid Details PAGEREF _Toc340175977 \h 20Figure 8: Solenoid Cross Section PAGEREF _Toc340175978 \h 20Engine PAGEREF _Toc340175979 \h 20Mounting System PAGEREF _Toc340175980 \h 21Risk Assessment PAGEREF _Toc340175981 \h 22Table 9: Risk Items PAGEREF _Toc340175982 \h 22Table 10: Risk Items, Continued PAGEREF _Toc340175983 \h 23Testing Plans PAGEREF _Toc340175984 \h 24Bill of Materials PAGEREF _Toc340175985 \h 24Timeline/Schedule PAGEREF _Toc340175986 \h 25Tables TOC \h \z \c "Table" Table 1: Project Information PAGEREF _Toc340176005 \h 5Table 2: Customer Needs PAGEREF _Toc340176006 \h 6Table 3: Specifications Review PAGEREF _Toc340176007 \h 7Table 4: Specifications, Continued PAGEREF _Toc340176008 \h 8Table 5: Induction System Compliance PAGEREF _Toc340176009 \h 10Table 6: Intercooler Compliance PAGEREF _Toc340176010 \h 13Table 7: Turbocharger Compliance PAGEREF _Toc340176011 \h 14Table 8:Boost Control System Compliance PAGEREF _Toc340176012 \h 18Table 9: Risk Items PAGEREF _Toc340176013 \h 22Table 10: Risk Items, Continued PAGEREF _Toc340176014 \h 23Figures TOC \h \z \c "Figure" Figure 1: Simplified Block Diagram PAGEREF _Toc340175997 \h 9Figure 2: Spike Geometry Comparison PAGEREF _Toc340175998 \h 11Figure 3: CFD Analysis of Spike/Restrictor PAGEREF _Toc340175999 \h 12Figure 4: Restrictor Geometry PAGEREF _Toc340176000 \h 12Figure 5: GT Power Simulation Schematic PAGEREF _Toc340176001 \h 15Figure 6: GT Power, Efficiency Results PAGEREF _Toc340176002 \h 15Figure 7: Solenoid Details PAGEREF _Toc340176003 \h 20Figure 8: Solenoid Cross Section PAGEREF _Toc340176004 \h 20Table SEQ Table \* ARABIC 1: Project InformationProject #Project NameProject TrackProject FamilyP13222FSAE Turbocharger IntegrationVehicle Systems and TechnologiesStart TermTeam GuideProject SponsorDoc. Revision20121Dr. NyeRIT Formula SAE TeamProject DescriptionProject BackgroundGroup of students that design and build a small open wheeled racecarVehicle must satisfies the safety requirements Limitations: 20 mm diameter, maximum displacement of 610 cubic centimeters.Fuel economy emphasis: 10% of total pointsBest balance between power and fuel efficiency with significant physical limitationsProblem StatementSuccessfully integrate a turbocharger into the Yamaha WR450F engine package on the Formula SAE race car. Objectives/ScopeDevelop accurate engine simulationIncrease generated horsepower to 60 HP and torque to 45 ft*lbsElectronic boost control to maximize power and fuel efficiency Package components into vehicle using 3D CAD softwareCorrelate simulation results to dynamometer performance Robust mounting to withstand extreme vibration and thermal environmentDeliverablesEngine Simulation, Dyno DataInduction/Exhaust SystemTurbocharger/Mounting SystemBoost Control SystemExpected Project BenefitsIncrease power output of the lightweight single cylinder engine without excessive fuel economy penalty. Increased power will allow for faster acceleration, higher top speed, and the ability to use additional aerodynamic downforce. Core Team Members: Kevin FerraroPhil VarsTyler PetersonAaron LeagueBrian GuentherIan McCuneAssumptions & ConstraintsSingle cylinder engine: 2010 Yamaha WR450FComplies with all Formula SAE rules20mm restrictorThrottle->restrictor->compressor Maximum weight gain: 15 lbsIssues and RisksIncreased power generation will negatively affect fuel economy of engine if not properly tunedImproperly operating turbocharger can either be inefficient or damaging to engineHigh exhaust temperature and severe vibration will require robust mounting scheme Customer Needs ReviewThe following shows the customer needs for the implemented turbocharger package. Table SEQ Table \* ARABIC 2: Customer NeedsCustomer Need #ImportanceDescriptionCN15Overall Horsepower and Torque Gains: CN25Optimized ECU Map for Best PerformanceCN35Consistent Engine PerformanceCN45Necessary Engine Internals are Included with SystemCN54Adequate System CoolingCN64Sufficient Dyno Testing and ValidationCN74Optimized Turbo Size for ApplicationCN84Meet FSAE Noise RegulationsCN93Quick Throttle ResponseCN103Easy to Access in CarCN113Compact Design in CarCN123Fit Within Constraints of Current ChassisCN132Easy to DriveCN142Drivetrain Components Designed for Power IncreaseCN152Design for Intercooler Location (if required)CN161Readily Available Replacement PartsCN171Simple Interface with Current EngineCN181Maximized Use of Composite MaterialSpecifications OverviewTable SEQ Table \* ARABIC 3: Specifications ReviewSourceFunctionSpecification (metric)Unit of MeasureIdeal ValueComments/StatusS1CN1EnginePeak Power OutputHp and ft-lbs>= 60hp 45 ft-lbs?General increase overall can also compensateS2CN1, 2IntakeMass Air Flow g/s>=40?Maximize for restrictor, based on restrictor geometryS3CN1, 2, 9, 13IntakePlenum Volumecc>=1000?Proper plenum size required for acceptable throttle response and resolution S4CN3SensorsSensor VoltageV5Proper voltage and grounding provided to each sensor for proper measurement and signal ?S5CN1, 5, 15IntercoolerAir Temperature ReductionDeg F>=20Increase density of airS6CN1, 2, 5IntakeManifold Air TemperatureDeg F<=100S7CN1, 7, 9TurboTurbine Shaft RPMrpm~100,000Depending on turbo chosenS8CN1, 7, 9TurboIntake Manifold Pressurepsi>=20 Amount of "Boost": Map of boost pressure vs. load/throttle position determined through engine simulationS9CN7, 9, 13TurboPeak Compression by RPM (specified)rpm<=6000S10CN1,2, 3, SensorsAir Fuel Ratio Range12.6<x<17.6Controlled by ECU, necessary for proper engine operation, possible through wideband lambda sensorTable SEQ Table \* ARABIC 4: Specifications, ContinuedSourceFunctionSpecification (metric)Unit of MeasureIdeal ValueComments/StatusS11CN1, 3SensorsManifold Air Pressure Rangepsi0-30 Sensor operates across expected pressure rangeS12CN3,4,13, 17TurboPressure to Actuate Wastegatepsi>=20Determines minimum boost pressure levelS13C3,C4TurboSupplied oil pressurekPa>=170Manufacturer specificationS14CN1,11,17ExhaustFlow Rateg/s>=100S15CN8ExhaustNoise LeveldBa<110Based on FSAE regulationS16CN3,5,7,16TurboMax Temperature of TurboDeg F<800Manfr's recommendationsS17CN7,11,18SystemOverall Maximum Weight Increaselbs<=15Maximum acceptable weight gain, based on laptime simulationS18CN1,3,4,6EngineCompression Ratio~10:1Max achievable without engine knockS19CN1,13EngineMax Power Design RPMrpm~9000S20CN1,13EngineMax Torque Design RPMrpm~7000S21CN1,3,13EngineMax Spark Advancedeg40-45Exact value determined through empirical testingS22CN4,16,18FundingCost to Formula Team$$$<100Funding/Sponsorship will be requiredSystem ArchitectureThe following shows a simplified block diagram for the components of the system: Figure SEQ Figure \* ARABIC 1: Simplified Block DiagramCompliance with RequirementsInductionThe induction system is composed of the throttle body, restrictor, compressor and intercooler. The following table shows the specifications relevant to the induction system.Table SEQ Table \* ARABIC 5: Induction System ComplianceSpecification Value Compliance Verification Mass air flow >= 50 g/s CFD Pressure measurementsRestrictor Diameter <=20 mm Design Measure Plenum Volume >=1000ccCAD, 3D modeling Volume measurementAir temperature reduction >= 50°FCFD, heat transfer analysisThermocouple measurementIntake manifold pressure range0-30 psiDesign, component selectionComponent pressure capacity will be tested during dyno data collectionThrottle ModulationNear linear, Throttle position vs flowCFD analysis Dynamometer measurementThrottle/RestrictorThe throttle modulates the airflow into the engine. The throttle assembly consists of a spike-shaped plug that controls the size of the opening into the restrictor. A cable connected to the gas pedal of the car pulls the spike away from the opening to increase the flow rate of air. A spring returns the spike to the rest position against the opening of the restrictor. This plugs the restrictor for the engine to idle. The spike geometry has significant influence on the nature of the throttle modulation. As the spike is pulled away from the restrictor, the area open for air flow changes. It is critical for the driver to have accurate and predictable feedback for the throttle inputs from the gas pedal. There must be a linear response between the throttle position and the flow rate of air into the engine. The diameter along the spike can be varied to tune the response of the airflow. In addition, the throttle/spike assembly must allow for proper pressure recovery after the restriction. This is necessary in order for the engine to make the maximum amount of power. CFD analysis was performed to determine a suitable geometry that would allow for a linear response to flow rate and complete outlet pressure recovery. The following graph compares CFD results from two different spike profiles. The response of mass flow rate and outlet pressure is plotted against throttle position. Perfectly linear modulation would result in a linear line extending from minimum flow rate at 0% throttle position to maximum flow rate at 100% throttle position. Figure SEQ Figure \* ARABIC 2: Spike Geometry ComparisonThe new spike (blue and red lines) show a relationship that is closer to linear than the original spike. The following figure shows an example screen shot of the CFD analysis that was performed on the assembly. The inlet boundary condition was air at atmospheric pressure and the outlet boundary condition is a flow rate based on engine displacement and speed. Figure SEQ Figure \* ARABIC 3: CFD Analysis of Spike/RestrictorThe following figure shows a drawing of the profile of the restrictor. The minimum diameter, 20 mm, is specified in the Formula SAE rules document. Figure SEQ Figure \* ARABIC 4: Restrictor GeometryIntercoolerThe intercooler component increases the efficiency of the turbocharger by cooling the incoming air. The energy density of the incoming air increases as it cools. The following table shows the relevant specifications for the intercooler. Table 6: Intercooler ComplianceSpecification Value Compliance Verification Air Temperature reduction >=50°FThermal analysisThermocouple measurement Manifold air temperature<=100°FThermal analysisThermocouple measurement The intercooler will be manufactured from purchased intercooler stock. There are three dimensions of the intercooler: thickness, width, and length . The induction stream into the engine passes through the plane made by the thickness and width dimension, and the cooling stream passes through the plane made by the length and width dimensions. Intercooler stock is only commercially available in a limited number of thicknesses. The intercooler width and thickness dimensions control the amount of warm, compressed flow that can pass through. The length of the intercooler controls the amount of cooling that occurs. Longer sections result in additional cooling.TurbochargerThe turbo charge that will be used is manufactured by Honeywell. It is a model GT06 which was originally designed for a small displacement 2 cylinder diesel engine. The relevant specifications for the turbocharger are listed below. Table SEQ Table \* ARABIC 7: Turbocharger ComplianceSpecification Value Compliance Verification Peak Power Output60 hp, 45 ft*lbsGT Power simulationDC Dynamometer measurementPeak efficiencyEfficiency maps,GT Power simulationDC Dynamometer measurement: Fuel consumption vs. powerPressure to Actuate Wastegate20 psiPurchased part Test stand measurementMax Temperature of Turbo<800°FAssumption: no modification from production partThermocouple measurement Supplied Oil Pressure 170 kPa (24.7 psi)Tapping into oil return line of engineOil pressure sensor, tapped into oil return lineMass flow rate, compressor>=40 g/sCompressor efficiency mapDC Dynamometer measurementMass flow rate, turbine>=100 g/sTurbine efficiency mapDC Dynamometer measurementThe selection of this turbocharger is primarily based on engine simulation using the software package "GT Power". This is a 1-D simulation of the performance of an engine and its associated flow system. The simulation was used to compare the performance of 2 different models of turbochargers offered by Honeywell. The following figure shows the schematic of the engine simulation. Figure SEQ Figure \* ARABIC 5: GT Power Simulation SchematicEach component of the engine system is represented through its own module. The schematic follows the flow through each component and shows connections between components. The software simulates engine performance at several discrete operating conditions and can show a variety of performance characteristics. When comparing turbochargers it is very useful to compare the efficiency map of the compressor with the load points of the engine shown.Figure SEQ Figure \* ARABIC 6: GT Power, Efficiency ResultsExhaust SystemThe design of the exhaust system will optimize the efficiency of the turbine. This will in turn increase the overall efficiency of the turbocharger and improve engine performance. The shape of the header and exhaust will have a large effect on the performance of the turbocharger. The highly pulsed flow of the single cylinder exhaust is far from an ideal steady flow. There are however, several constraints that limit the design. The exhaust must fit in the car with all of the other components, the shape must be possible to fabricate, and the heat from the exhaust must not cause damage.Specification Value Compliance Verification Fit in the Car1CreoSolid modelingEfficiency of turbine>40%GT-PowerDyno TestingExternal Temperature<800 °FGT-PowerDyno TestingBend Radius3 inCreoSolid ModelingSeveral iterations of exhaust design have been modeled in Creo and simulated in GT-Power. The initial (red line) design simulated in GT-power was similar to what was used on F20 and would not actually fit in F21. The design #1(blue line) was the first iteration of a header that would fit in F21 but an arbitrary exhaust after the turbo. Design #2 (green line) had a revised header geometry and a more reasonable geometry after the turbo. Figure 7: GT-Power: Power and Efficiency results, Screen shot of header design #2 (green)It is clear from the initial simulation that the performance of the turbocharger, and therefore the engine, is very sensitive to the exhaust design. It is evident that further analysis is required to optimize the performance of the system.Boost ControlElectronic boost control will be accomplished through the MoTec M400 engine control unit (ECU). The ECU will vary the level of boost delivered to the engine by actuating a solenoid that controls the pressure applied to the wastegate. Boost control is critical to the performance of the system by allowing the boost to be reduced to increase efficiency where needed.The following table shows the relevant specifications for the boost control system.Table SEQ Table \* ARABIC 8:Boost Control System ComplianceSpecification Value Compliance Verification Peak Power60 hp, 45 ft*lbsGT PowerDC Dynamometer measurementPressure to actuate wastegate20 psi Purchased partBench-top testing Boost control is achieved through the wastegate and solenoid control valve. The wastegate is a valve that can open to allow exhaust gas to bypass the turbine of the turbocharger. The wastegate is held closed through the force of a spring. The spring is attached to a diaphragm that is connected to the pressure of the plenum. When the pressure in the plenum builds to a certain level, the force on the diaphragm overcomes the force of the spring and the wastegate is pushed open. Exhaust gas bypases the turbine through the wastegate, slowing the turbine. The boost pressure falls, reducing the pressure on the diaphragm, and the wastegate closes. The boost control level will be electronically controlled by positioning a three-way solenoid in-line between the plenum pressure and the diaphragm. This three-way solenoid connects the diaphragm volume, the plenum volume, and a vent to atmosphere. To increase the boost level, the solenoid will open so that pressure is routed away from the diaphragm and vented to atmosphere. The boost pressure is not exerted on the diaphragm so the wastegate remains in the closed position, and the exhaust gasses are routed through the turbine. To decrease the boost pressure, the solenoid closes so that pressure is routed to the diaphragm. The boost pressure is applied to the diaphragm, which opens the wastegate. Exhaust gasses are routed through the wastegate to bypass the turbine. The figure below is a simplified block diagram of the system. Figure 8: Boost Control Block DiagramIn order to accurately control the level of boost, the ECU will control the solenoid through pulse width modulation (PWM). The controller will vary the duty cycle of the solenoid according to a PID control algorithm to achieve the desired boost level. The target boost level will depend on the desired operating characteristics of the engine. When maximum power is needed, the boost level will be increased to generate extra power. When fuel efficiency is a priority, the boost level will be decreased so that the engine burns less fuel.A solenoid from MAC Valves has been selected for use in the boost control system. The part number is 35A-AAA-DDBA-1BA. It is a miniature 3-way valve with 1/8" NPT fittings. The solenoid accepts PWM control signal from the ECU. The following figure is a page from the MAC catalogue with additional details on the valve. Figure SEQ Figure \* ARABIC 7: Solenoid DetailsThe following figure is a cross section of the solenoid, with the ports and positions labeled:Figure SEQ Figure \* ARABIC 8: Solenoid Cross Section EngineThere will likely be few internal modifications to the engine initially. It is possible that with the increased power some components may need to be replaced with stronger alternatives. However, until there is a better understanding of the performance potential and the durability of the factory components no modifications will be made.Mounting System The mounting system's main function is to hold the turbocharger assembly firmly in place, and constrain it in all axes of rotation/translation. Using the main roll hoop as a base, standoff tubes are welded to nodes that already support engine and chassis loads to maintain stiffness. Pending dynamometer testing and verification of inertial loads/vibrations, mounting may be modified to accommodate stiffness and strength requirements. In that case, alternative options such as mounting the turbocharger assembly to the chassis may be presented, as well as a combination of support from the roll hoop and chassis.Specification Value Compliance Verification Turbo axis of revolution orientation Normal to gravity, ±10° 3D CAD Visual/Inspection Oil outlet direction Parallel to gravity, ±35° 3D CAD Visual/Inspection Connections to chassis Compliance for CTE mismatch, vibration Design and analysis Assembly, testing in operating conditions Risk AssessmentTable SEQ Table \* ARABIC 9: Risk ItemsID Risk ItemEffectCauseLikelihoodSeverityImportanceAction to Minimize RiskOwner1Poor Fuel EfficiencyLow Fuel Economy ScoreEngine not tuned properly for endurance133Create separate fuel maps for each individual eventPowertrain Engineer2High Car CGReduced Cornering AbilityTurbo location not optimized122Turbo placed within crash structure, allows for lowest placement possible according to rulesChassis Engineer/Structures Engineer3Insufficient Oil FlowBlown Turbo/Short Turbo LifePoor analysis of oil pressure source236Test oil pressure and flow of source prior to turbo implementation, follow manfr's recommendations on oil supplyPowertrain Engineer4Thermal ManagementChassis, engine, seat, or fuel over allowable temperatureUnexpectedly high heat generation 212Analyze chassis airflow and design for cooling, design in flexibility for additional cooling mechanismsChassis Engineer/Thermal Engineer5Engine VibrationTurbo Mount FailureInsufficient structural analysis122Design with vibration in mind. Verify components are constrained properlyStructures Engineer6Thermal Expansion StressesAdditional stresses on mounting componentsThermal CTE mismatch between exhaust components and mounting components122Design compliance into mounting system to relieve thermal expansion stresses, ie bellowsThermal/Structures engineerTable SEQ Table \* ARABIC 10: Risk Items, ContinuedID Risk ItemEffectCauseLikelihoodSeverityImportanceAction to Minimize RiskOwner7Improperly Tuned EnginePoor overall engine performanceLack of time to properly tune engine on dyno236Schedule must include plan to have plenty of engine testing time on the dynomometerPowertrain Engineer8Lack of Available Space in ChassisHeavy plumbing and inefficient routingNot all locations analyzed for optimal routing212All project members agree with location and plumbing plan prior to implementationChassis Engineer/Structures Engineer9Improper Turbo SizePoor overall engine performanceInaccurate initial analysis and data acquisition133Use accurate and realistic parameters in engine simulation to make best selectionPowertrain Engineer/Project Manager10Welded Joint FailureStructural failure of exhaust plumbing, release of exhaust gassesCracking/fracture of welded joints within exhaust plumbing122Use proper welding techniques to assure high quality weld. Mounting system not to rely on support through welded sections. Structures Engineer11Engine FailureDestroyed EngineOverboost, internal component failure133Use high-performance aftermarket components, reduce friction through coatings, control boost to acceptable levelsPowertrain EngineerTesting Plans Testing will be centered around the DC Dynamometer facility that is maintained by the Formula SAE Team. The DC dynamometer will measure torque, speed, and various temperatures and fluid pressures. In addition, the ECU software allows for the monitoring of all normal engine operating parameters such as oil pressure, oil temperature, coolant temperature, spark and fuel information. The dyno control software can read and log the telemetry from the ECU along with the sensors on the dyno itself. It also allows the user to set a desired engine speed to allow precise tuning.Bill of MaterialsBill of MaterialsAssemblyItem QtyDescriptionTurbocharger????Garret GT-061?Turbo Manifold????Ti 1.5" .020" wall tube10 ftExhaust tubing?Ti bellows1Exhaust bellows?Ti .125" thick plate2 ft^2Plate for manifold flanges?Ti o2 sensor bung1Bung for engine sensor?Ti thermo couple bung2Bung for measureing exhaust gas temperatureMuffler????Ti .062" thick plate2 ft^2Titanium plate for muffler ends?Muffler packing1 kgFiber glass muffler packing ?Composite muffler can16" diameter 18" long carbon fiber tubeIntake ????Intercooler core16"x9" 1.5" thick heat exchanger core?Composite intercooler tank2Endtanks for intercooler ?Al 1.5" .049 wall tube10 ftIntake tubing?1.5" ID silicon hose1 ftIntake tube joints?Hose clamps8Intake joint hose clamps?Al fuel injector bung1Fuel injector weld on bungTurbo Mount????Mounting tube3 ft.5" OD .035" wall 4130 tube?MM-2 rod ends36-32 rod ends Timeline/Schedule -325120469265To keep the project on schedule, a timeline has been drafted. This timeline will be used to organize the manufacturing process for each component. ................
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