How Formula Student FSAE can write Result and Discussion, Conclusion and Further Study

It is an example only, please read previous blogs for details.

Result and Discussion (Group)

Vehicle System was divided in to 4 gropes: Powertrain, Chassis, Suspension and Driver Control. Design of Powertrain was further divided into 3 sections; Engine, Auxiliary and Transmission. My work is related to Main engine, intake and exhaust system optimization. In below table requirement from different group is explained; these requirements were generated from powertrain team members, MSc Vehicle Level Group members and FASE Approval Judges. As physical calibration, durability and performance testing is not finished yet, there will many more interrelated performance points such as vehicle acceleration, noise vibration.    For these Group–requirements team meeting were organized and accordingly agreement were taken; these Group requirement with Agreement is discussed in below table; also scheme / effort estimated from my side is given in below table. 

Group – Requirement	Result Achieved / Agreement	Scheme / Effort
Transmission – Keep Torque High	Engine : Max Torque 57 Nm@11000RPM	After each iteration results were shared with Transmission. After optimizing whole Intake and Exhaust parts this performance was achieved.
Transmission – Keep Torque Smooth	Pros: 9000-12000RPM torque is almost constant 55 Nm.  Cons: Between 5000 to 7000 RPM Torque decrease from 40Nm to 35 Nm then rise to 45Nm.	To keep torque smooth, Sharp Peak Torque (70Nm at 11000RPM) deign was rejected. Smaller but more smooth torque design was selected (57Nm at 11,000RPM)
Transmission – Zooming requirement	From 1000 to 4000 RPM Output Torque become 0 to 40 Nm	By further optimizing Intake Silencer This can be improved as mentioned in report.
Cooling System – Provide Total Heat Generated	A Graph was provided to Cooling System for Intake Air Mass Flow Rate. (such as 0.02 Kg/ sec at 11000 RPM)	By Multiplying Air Mass Flow Rate and Caloric Value Cooling Team can calculate Total Heat Generated.
Fuel System  -  Provide Injector Sitting Space on Intake Manifold	Intake Manifold Injector O Ring Compression 18%  and Filling Ratio 82% is as per standard	In Intake Manifold hole is designed for Injector Sitting and Leakage Presentation.
Fuel System  - Provide Fuel Delivery Rail mounting on Intake Manifold	Two M6 Bolt Blind Hole (with Tolerance +/-0.05 mm in X, Y and Z with respect to Injector Hole) will be provided for Rail.	Injector Installation Height, Co-axiality, Concentricity, Injector Spray Angle, Runner Dia etc have been explained in report.
Fuel System , Cooling & Lubrication System – Component Safe Assembly on Engine	Engine Envelop is considered with 5 ° with 10 mm movement in X, Y & Z direction so that enough free space can be provided for nearby parts such as Fuel Hose, Oil Pump,	Exhaust System is kept far away with Heat Shield Cover. Engine Envelope is kept bigger for safe design.
Driver Control -  Wiring Harness and Connector	CAD data is made for all sensor location so that Driver Control can measure length of required wire. Also Connector and wire requirement is discussed with Driver Control Team.	Weekly Team Meeting for agreement on Sensor Design, supplier and location on engine. (Sensor – Knock Sensor, Temperature Sensor, MAP Sensor, TPS sensor, CAM sensor etc)
Driver Control – Sensors     (Inlet Air Temperature Pressure , Mass Flow, Oxygen etc)	Temperature Sensor – On Air Cleaner           Pressure Sensor – On Plenum                       Mass Flow Sensor – After Restrictor on Intake Manifold; Oxygen Sensor – M10 Screw Hole is provided at two places before and after Catalyst in Exhaust Manifold	Hole on Air Cleaner is provided for Temperature Sensor mounting. CFD and guidelines is mentioned for Pleasure Sensor Location Freezing on Plenum. Also to avoid Electromagnetic Noise all sensor wires must be shielded twisted pair or always from high voltage wires of Spark plug, Starter Motor etc
Driver Control – Electronic Throttle Body & TPS	Throttle Body Bore, Shat Dia, WOT, Full Close is fixed. 6 Pin Bosch Throttle will be used; 2 Pin for Motor, 3 Pin for Two TPS, 1 For common Ground.	As per FSAE rules, DFMEA for Electronic Throttle is mentioned in report.
Driver Control – Accelerator Pedal Design Change	Agreement to use Electronic Sensor in Accelerator Pedal as Electronic Throttle will be used.	Team Meeting for agreement from Chassis for Accelerator Pedal Mounting on Body Panel
Dyno –  Map Sensor Performance Verification	Air Flow Simulation result shared with Dyno Testing Group for Verification. Sensor is placed away from runner and Restrictor; where Air velocity is almost constant in plenum.	A highly accurate and sensitive sensor-1 will be placed in place of Bosch MAP sensor. Pressure Reading from Sensor-1 and Bosch Sensor will be compared for location fixing on Plenum Body.
Dyno –  Temperature Sensor Verification	0 to 5V, Range -40 °C to 200 °C, Accuracy +/- 0.5 °C	Two-Wire Thermocouple type sensors fitted in Air Cleaner. (i.e. before Throttle)
Dyno – Throttle Fail Safe Mode Setting	Aluminum stopper is given in Casting of Throttle Body so if Valve/shaft/spring or electrical failure occur vehicle speed will become 30 Km/h. Stopper will keep valve angle 12° in case of sudden failure.	If throttle body fail and vehicle is moving at very high speed; the vehicle speed should not become 0 as other chasing vehicle can hit from behind and cause severe accident.
Dyno – Throttle and Vehicle Idle Speed Control	Idle Engine Speed = 1000 RPM.	Throttle Full Close Angle is set 5 °. Aluminum stopper is given in casting to maintain this angle.
Dyno – Throttle and Vehicle Speed Fluctuation	Throttle Motor Angle Resolution =          +/- 0.06 ° Maximum; 0.06 differ in angle leads to differ Inlet Air Volume and fluctuate engine RPM by +/- 25.	More than +/- 25 RPM variation will lead to drivability problem as vehicle speed variation will became substantial.
Vehicle Stability	Engine is located near rear wheel and Engine height of centre of gravity is kept low.	This design will help in Braking and Steering Control. ( Front Weight Transfer and Cornering Side Weight Transfer)
Chassis Frame Strength	Three Point Hydraulic Mounting used for Engine Mounting.  Aluminum, Plastic, Steel Alloy will be used to keep engine weight low.	Hydraulic Mounting and Lower weight of engine
Noise Approval:  Sound Level	Physical Test Require to confirm this; As by simulation on Torque Fluctuation due to silencer can be checked.	Proper Mounting and Assembly location on Chassis design for Intake and Exhaust Silencer.
Safety - Firing Frequency Resonance and Chassis Strength	First Order Engine Firing Frequency = (Max RPM/60) X (Number Of Cylinders / 2*) = (16000/60)X(4/2) = 533.3  (* For Four Stroke)	Natural Frequency of Each Intake and Exhaust Component is kept above (533.3) Engine RPM frequency. There will not be resonance between Engine Vibration and individual component.
FSAE Approval	Tail Pipe End is kept just 40 Cm behind Rear axle and 20Cm above ground.	Engine height of centre of gravity is kept low; Inclined tail pipe is used to accommodate length of Tail Pipe.
FSAE Approval	All part positioned under defined boundary such as air filter, intake duct and exhaust tail pipe. Cover Intake System parts if below 350mm height.	Chassis Frame design has mounting and bolting position as per Intake system component requirement.
FSAE Approval	Calibration, safety and driver control related rule has been followed while buying Throttle. Bosch can meet all specified FSAE regulation and Motec ECU can do matching with it.	Two separate TPS (both reading within 10%), Cover is provided on Throttle to prevent oil, grease etc, Two return springs provided to throttle shaft for safe return.

Conclusion:

This report of Engine Design has broadly and critically evaluated both the aspects: 1^st Managerial and 2^nd Technical for designing Intake and Exhaust System for FSAE race vehicle. The 1^st Part Managerial analysis for Engine development has been presented considering internal and external environment using PEST, SWOT, Financial Investment, Human Resource Requirement, Location, Responsibility Division and Scheduling. 2^nd Part Conventional Technical steps such as Design, Testing, Quality and Procurement have been explained in detail using standard tools of costing, scheduling and controlling process. Techno-commercial Management issues such as Value Analysis/Value Engineering, Cost Control, Risk Management etc has been identified and countermeasure to each possible failure has been presented in Management report. Race Day technical, environmental, ecological, social and managerial issues have been considered while designing each component. Certainly Engine Design report is very inclusive and investigative; It is agreed with MSc group to consider this proposal for financial go ahead as soon as possible so that further steps can be taken to meet FSAE 2016. Addition to FSAE participation, there is an element of design experience and technical learning by this project; following list comprises design experience and leaning achieved by this project.

Component	Design Experience	Technical Learning
Electronic Throttle	45mm Bore, Full Close Angle 5, WOT 85, Two TPS 0 to 5V, 10mm Shaft Dia, Aluminum Body with Steel Valve, DC three phase motor.	Fail Safe Mode, Bore Dia Optimization, CAD Data making
Diffuser Restrictor	Length 250mm from 45mm to 20mm, Length 250mm from 20mm to 60mm, Steel Body	CFD for air flow
Plenum	2.8 Liter, Restrictor Inlet at Centre of plenum i.e. equidistance from all runners, Aluminum Sand Casting with Machining	Plenum Noise Optimization, CAD Data Making and Strength Simulation
Runner	Length 260mm , Dia 35mm Throughout, Aluminum Sand Casting	Method to achieve High Constant Torque, Tolerance Analysis for Injector
Exhaust Manifold	Pipe Length 240mm, Dia 38mm Throughout, Cata Volume Space 2.25 Liter, Exit Area 2100 mm2	Back Pressure impact on Volumetric Efficiency
Muffler	Simple Perforated Type, Inlet Pipe L 250mm , out let pipe 59mm, Inlet Dia 75mm, Out Let Dia 75mm	Effect of Muffler shape on Torque output
Engine	57Nm @ 10,000 RPM (9000 to 12000 Constant Torque)	Engine Simulation

Further Study:

Previous batch has worked on Intake and Exhaust System Design. Similarly our focus was on improvement in previous year engine performance by improving previous intake and exhaust system designs so that we can get approval to participate in FSAE Race however we have not focused on advanced technology. Further study should not be done in improving our proposed designs or FSAE approval related technology but further study must focus on new technology.  Further study must be done in following areas; these are new technology in Electronic Fuel Injection system so that it can meet FSAE regulation also.

Component Function	Parameters
Variable Intake Runner	Length and Dia of each runner will be different for different cylinder. As a result engine cylinder will give equal power and torque. It also helps in balancing of engine so noise and vibration reduce.
Open Valve Injection with Long Reach Injection  with Dual Injector per Cylinder	To negate injection delay, long nozzle length injector is being used for Electronic Port Injection System. This can be tried for our Engine also with small modification in Intake Manifold design and Injection Mapping.
	As Gasoline Direct Injector is not permitted; Open Valve Liquid Fuel Injection just when intake valve are open; it’s like gasoline direct injection in combustion process.  If GDI can give constant torque and increase torque by 15-20%; Similarly Open Valve Injection can give 5 % improvement in torque. Additionally NOx reduce by Fuel cooling of Combustion chamber.
Electronic Throttle Torque Based Mapping	Torque Based Mapping can be done only with Electronic Throttle; It has correction factor to make keep torque constant by changing amount of fuel injected and opening throttle accordingly.
Intake Silencer Improvement	There is further scope in Intake Noise reduction. Current Design is not very satisfactory.
Muffler Design Improvement	There is further scope in Intake Noise reduction. In current system there is abrupt torque variation.
Single Cylinder 600 cc Engine	As per our benchmarking result; Further study can be done to use single cylinder Engine from KTM. As single cylinder mass is very less, it can improvement vehicle performance.
Knock Improvement	Single knock sensor per cylinder for better measurement of knocking. This will improve in between fueling and vibration control. This ll ultimately improve vehicle drivability and
Use Integrated Temperature and Pressure Sensor and Mass Flow Sensor at two places.	By measuring temperature and pressure near air cleaner and then near runner, correction factor can be calculated for correcting amount of fuel required. This will leads to improvement in fuel efficiency.
EGR (Exhaust Gas Recirculation)	FSAE allow waste heat usage by 100%. EGR must be design to improve torque output, for intake air mixing and cooling at high speed air cooling can be used. For low speed intercooler will be required which can lead to cost up. So EGR valve can be calibrated to switch on when speed is above 80Km /hour - inlet change cooling simulation required to confirm vehicle speed.