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The public transport in India is gradually shifting towards electric mobility. Long range in electric mobility can be served with High Voltage Battery (HVB), but HVB can sustain for its designed life if it’s maintained within a specific operating temperature range. Appropriate battery thermal management through Battery Cooling System (BCS) is critical for vehicle range and battery durability This work focus on two aspects, BCS sizing and its coolant flow optimization in Electric bus. BCS modelling was done in 1D CAE software. The objective is to develop a model of BCS in virtual environment to replicate the physical testing. Electric bus contain numerous battery packs and a complex piping in its cooling system. BCS sizing simulation was performed to keep the battery packs in operating temperature range.

Transmission of vibration and noise to the occupants and especially driver contributes significantly to the quality perception of the motor vehicle and eventually, it affects the overall ride comfort. These forces mainly reach to customer through tactile locations, i.e. floor, gearshift lever, steering wheel and seat. Showroom/Parking customer drive pattern of a vehicle evinces the steering system and driver’s seat rail vibration as strikingly linked aspect to evaluate human comfort [1]. This paper deals with the study of vibration at steering wheel and seat affecting human comfort at engine idle rpm with AC ON and OFF condition for passenger vehicles. The transmissibility of engine and radiator induced vibrations has been investigated with respect to modal alignment of steering and seat system.

In previous work, AC Compressor Cycling (ACC) was modeled by incorporating evaporator thermal inertia in Mobile Air Conditioning (MAC) performance simulation. Prediction accuracy of >95% in average cabin air temperature has been achieved at moderate ambient condition, however the number of ACC events in 1D CAE simulation were higher as compared to physical test [1]. This paper documents the systematic approach followed to address the challenges in simulation model in order to bridge the gap between physical and digital. In physical phenomenon, during cabin cooldown, after meeting the set/ target cooling of a cabin, the ACC takes place. During ACC, gradual heat transfer takes place between cold evaporator surface and air flowing over it because of evaporator thermal inertia.

In an automotive power train system, the differential gear system plays a vital role of enabling the vehicle to transfer the engine torque to the wheels. The differential system consists of complex system of gears which are meshed with each other. Effective lubrication of the differential system ensures that the metal to metal contact between the gears is avoided. In addition, the lubricants also acts as a thermal medium to effectively dissipate the heat produced due to frictional resistances. For dipped lubrication system, the use of lubrication oil leads to a loss of transmission power, and the loss increases with increasing rotational speeds. Prediction and an understanding of the transmission loss inside the differential system is important as it provides a means to increase the power transmission efficiency. In addition, it provides insights to optimize the lubrication methods, gear profile, and gear housings.

Currently automotive design is facing multi facet challenges such as reduction in greenhouse gases, better thermal management, low cost solution to market, etc. Considering these challenges, effort has been taken to improve thermal management of engine while optimizing the cost of engine. Engine Lubrication system consist of Engine oil and oil cooler, which play vital role in thermal management as well as optimization of frictional losses by ensuring proper lubrication and cooling of engine components. For better thermal management of engine, a lubrication system is designed without Oil cooler, proto type made and tested. This paper deals with evaluation of various engine performance parameter and engine temperature with and without oil cooler for light duty Diesel engines on passenger car application. Further solution of Oil cooler removal and Engine cooling improvement with the help of oil change is validated at vehicle level to understand real world behavior of the system.

Currently automotive industry is struggling for its sustainability to produce cost effective products with better or same performance. In this study, fuel return line has been converted from Viton/Hypalon material to Epichlorohydrin based material. In initial phase, technical specifications and material properties has been compared. In later phase, components were developed with modified material and validated at Test bed as well as Vehicle level to understand the material behavior in Real world usage. Further, test results were compared and results shows that the new material is able to cater vehicle application requirement in terms of reliability and durability with a good cost saving.

During endurance tests on new prototypes, it is often observed that test drivers come back with some feed back on clutch slippage. This is a typical example of subjective evaluation and at times it is found that it is the test driver's perception rather than the actual clutch slippage. To over come this problem, a new method has been evolved which captures the clutch slippage automatically and quantify that to the minutest details. This is achieved using GPS based instrumentation and software for automatic detection. This system is part of intelligent control which using the GPS determines the actual speed of the vehicle and also acquires the engine speed through RPM sensor which is converted into vehicle speed. Using a dedicated software program, variation in actual speed and calculated speed provides the information on clutch slippage along with the gear shift pattern during test driving.

Engine Monitoring System (EMOS) plays a crucial role towards engine safety and monitoring for low cost commercial vehicles not equipped with a full-fledged Engine Management System (EMS). The EMOS system mainly focuses on monitoring of coolant temperature, alternator belt failure, and lubrication oil pressure and coolant level indication This paper describes various engineering design considerations for balancing the application requirements with implementation costs. It also highlights some common pit-falls in detecting alternator failures leading to nuisance trips as well as system design considerations involved in matching the gauge indication accuracy with the coolant high temperature trip point. The system designer needs to take into account, difference between alternator belt slippage versus total belt failure condition and implement different control strategies accordingly.

Common rail direct injection technologies have enabled the development of very high power and torque for a given capacity of the engine. These high performance engines have very high brake mean effective pressures and peak firing pressures. These high pressures increase the blow-by gas flow in cylinder crankcase. Vehicle brake assist systems as well as some actuators on engine need the vacuum. The vacuum is generated by the vacuum pump driven by the engine cam shaft or separately as accessory drive. The air pulled for creating the vacuum gets mixed with the lubricating oil. This air mixture with the lubrication oil gets circulated in the blow by circuit. Collectively, blow-by gases and the vacuum pump oil with air carry substantial engine oil particles. These oil particles need to be separated before connecting to the air intake circuit to reduce oil consumption and to reduce exhaust emissions. Generally cyclone type oil mist separation systems are used on the automobile engines.

Electric radiator fan is a vital component within IC and EV passenger vehicle cooling system. However, due to its operation, it induces noise and in-cab vibration affecting human comfort level. This paper primarily focus on FMS (Fan Motor Shroud) assembly induced steering wheel vibrations in a vehicle under idle + AC ON condition. The entire NVH performance was cascaded from vehicle level to component level to evaluate for high steering wheel vibration and its transfer path analysis. Unit level vibrations study was also carried out using a rigid rig under controlled conditions. Based on FMS vibration analysis, it was observed that fan blade rotating imbalance leads the high vibrations within system. Thus, a balancing method with higher precision and accuracy was used to measure and balance the fan under all operating conditions. Sensitivity analysis had been carried out for fan imbalanced boundary conditions and operating speeds.

Vehicle thermal management system (VTMS) is a means of monitoring and controlling temperatures of vehicular components and aggregates to within optimum limits, thereby ensuring the proper functioning of the component or aggregate in an automobile. An integrated approach is required for developing VTMS, to satisfy the complex requirements of performance, reliability, fuel economy and human thermal comfort in modern vehicles. Fan motors and blowers play a crucial role in vehicle thermal management. These fan motors/ blower systems need to be designed in a manner such that there is minimum parasitic load on the prime mover. This work comprises performing Transient Powertrain Cooling (T-PTC) and Transient Air-conditioning (T-AC) simulation on a vehicle for prediction of parameters affecting fan operation of Condenser Radiator Fan Module (CRFM) during simulated city drive cycles.

This paper introduces a novel approach to automate PID calibration for closed-loop control systems and the creep control function in an electric vehicle. Through a comprehensive literature survey, it is found that this method is the first of its kind to be applied in the field of automated electric vehicle calibration for Creep function. The proposed approach utilizes a systematic methodology that automatically tunes the PID parameters based on predefined performance criteria, including energy consumption and jerk. To implement this methodology, the ETAS INCA FLOW software, which provides guided calibration methods for in-vehicle testing & calibration, is employed. The calibration process is performed on a real-time electric vehicle platform to validate the effectiveness of the proposed approach. The results of this study showcases the advantages of automated PID calibration for closed-loop control systems and creep control function in small commercial electric vehicle.