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Thermal Management System (TMS) is equally or more important part of Battery Electric (BEV)/Hybrid Electric vehicle (HEV) than an internal combustion engine (ICE) vehicle. In an ICE vehicle, TMS ensures performance of power train/engine, after treatment/exhaust system and HVAC (Climate control) whereas it connected with safety and Range anxiety elimination additionally for the case of Electric Vehicle. Electric powertrain is not a new technology to the world but the technology is evolving in last few decades, to overcome the cost and make it commercially viable, charging infrastructural development and elimination of Range Anxiety. In last few years, Indian automotive industry has taken some major steps towards electrification journey for both passenger car and commercial vehicle. In BEVs, Battery Cooling or Battery thermal management System (BTMS or BCS) and Traction cooling system (TCS) are couple with nearly conventional HVAC circuit used in any ICE vehicle.

Large number of studies have been carried out and references are available on the use of synthetic rubber with non-carbon black fillers. Use of carbon black reinforced natural rubber is very common in automotive applications especially suspension top cups, cab mounts, suspension bushes, engine mounts etc Carbon black plays key role in the alteration of the rubber compound properties to suit the end product requirements for hysteresis, stiffness, hardness, compression set etc. This paper gives experimental details, results, and conclusions on and effect of carbon black in natural rubber compound. Carbon black reinforced natural rubber formulations were made and keeping all other ingredients of the formulation constant including type of carbon black and by varying only the amount of carbon black dosage. Since the rubber components call for different specifications based on the end product requirements, it is not possible to have common rubber formulation for all the end products.

Recycle, Reuse, Repair have become a mantra today for cost reduction. More importantly it reduces the demand of natural resources and helps protect environment. There are many ways in which cutting tools can be recycled. Some examples are used up extra long drill [1] and used up crankshaft grinding wheel [2]. Used up indexable inserts can also be reused by grinding a groove to remove the blunt/dull portion [3], selecting an application where the unused portion of a large cutting edge can be put to reuse [4], reuse by grinding a corner radius to remove the blunt/dull portion [5]. This article explains the concept of reuse of used up tangentially mounted plain inserts and shows that such mounting is best suited for the recycling of indexable inserts and can substantially reduce the tool cost. This recycle can reduce the consumption by almost 50% or more depending on the nature of dullness of insert during the initial use. Conserving natural resources is therefore a good possibility.

Increasing fuel cost and constant pressure to maximize the fuel economy are forcing OEMs in India to look for alternate engine cooling mechanism which will minimize the power take off from the engine without affecting the system reliability. Aim of this paper is to analyze the potential benefit of incorporating Electro-magnetic fan (EMF) drive in terms of fuel economy and reduced load on the engine. These benefits were compared with the conventional viscous coupled fan drive system. In vehicle with viscous coupling, fan RPM is based on the ram air temperature at coupling face which takes heat from turbo-charged air and coolant. On the other hand, EMF drive have a separate controller and control the fan RPM based on the coolant temperature enabling itself to respond directly to changes in the heat load as compared to viscous coupling having indirect representation of Coolant/charged air temperature.

With the advent of most advanced diesel engines the demand for upgraded engine cooling modules capable of handling more heat rejection in a smaller space is surging. Moreover, the variance in the operating conditions, i.e., the simultaneous cooling demands for peak load as well as partial load in different ambient conditions of the vehicle operation, broadens the scope of development of a cooling system. Also, the cooling system needs to be configured judiciously so as to cater effective cooling at peak loads and efficient cooling at partial loads. This research paper deals with a cooling system developed using modularity approach in order to have a control over tuning of subsystems for varying operating conditions and also to achieve the performance targets with a compact design adhering to packaging constraints. Kuli simulation of different designed configurations were carried out for identification of best concept.

Small goods carrier and passenger vehicles powered by Naturally Aspirated (NA) Direct Injection (DI) diesel engines are popular in Indian automobile market. However, they suffer from inherently high radiated noise and poorly perceived sound quality. This paper documents the steps taken to reduce the radiated noise level from such an engine through structural modifications of major noise radiating components identified in the sound power analysis. The work is summarized as follows; Baseline radiated noise measurements of power train and identification of major noise sources through sound intensity mapping and noise source ranking (NSR) in an Engine Noise Test Cell (ENTC) Design modifications for identified major sources in engine structure Vehicle level assessment of the radiated noise in a Vehicle Semi-Anechoic Chamber (VSAC) for all the design modifications. A reduction of 7 dB at hot idle and 4 - 8 dB in loaded speed sweep conditions was observed with the recommended modifications.

The micro hybrid system, also known as the engine stop start system, has recently gained prominence world over due to its considerable fuel saving potential and relatively low costs. In spite of being a relatively non-complex function, the stop start system works hand-in-hand with a wide range of vehicle systems and components, specially the starting system and the battery. Frequent idle stop periods during city driving conditions can result in excessive battery discharge and gradually lead to loss of engine restartability. Increased number of charging and discharging cycles tend to reduce the life of the battery significantly. Hence it is very essential that the micro hybrid vehicles have a system in place that monitors and maintains the battery status within its operating limits.

This paper is related to a vehicle with rear engine which is turbo charged and inter cooled. Due to packaging constraints the intercooler was placed in front of turbocharger and was exposed to hot air radiated out from the turbo charger. This was in turn reducing the efficiency of the intercooler. In such scenario, it is essential to shield the turbo charger from the intercooler for proper hot air management. Also rear engine vehicles don't have the benefit of ram air affect. This necessitates increasing the air entering in to the core of the intercooler. Both the above mentioned issues associated with such a vehicle was resolved by ensuring that the hot air from turbo-charge is guided away from the intercooler as well as the air flow to Intercooler is increased. Guiding or throwing out the hot air away from Intercooler was done by introducing a heat shield or a baffle between the two.

The direct injection common rail technology coupled with variable geometry turbocharger on the modern diesel engine has improved the diesel engine performance (power and torque) greatly as compared to the conventional diesel engine. Diesel engine performance is greatly dependent on the abundant air availability. And it is facilitated by Variable Geometry Turbocharger (VGT) in modern engines. The engines with variable geometry turbocharger offer quick response to the demand in various driving conditions especially in transient driving conditions. During transient driving conditions, the air intake system experiences a rapid air flow pressure and velocity changes. The pressure differentials across air intake system during transient events allow flow direction changes in the system. This kind of phenomenon generates unusual “Multiple Whoosh” noises in the air intake system of the sport utility vehicle engine.

Lift axles of heavy commercial vehicles are deployed to handle increased payload. These axles of Commercial vehicles are made of low alloy carbon steel materials. Lift axles are designed in hollow condition for weight reduction opportunity. Two types of tube materials are used for the manufacturing of lift axles. These are either Cold Drawn Seamless (CDS) tubes or Hot Finished Seamless (HFS) tube material. The vanadium micro-alloyed steel grade, 20MnV6 is an excellent choice for the manufacturing of lift axles. The 20MnV6 has favorable mechanical properties for lift axles and also offers good weldability. However, lift axles made of 20MnV6 when manufactured in hot-finished condition, shows significant scatter in terms of durability performance. This requires further heat treatment of 20MnV6 to be deployed for reducing the scatter in the material properties to reduce scatter in durability performance and thus increasing the reliability of the lift axles.

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.

Current Air Conditioning (AC) system uses hydrofluorocarbons (HFC) as refrigerant to transfer heat from cabin and cool the passengers. However, most refrigerants used today have severe environmental effects due to high global warming potential leading to global warming effects. Montreal Protocol and Kigali amendment calls for all nations to reduce refrigerant usage and transport sector being one of the main consumer of refrigerant, regulations regarding refrigerant usage and emission are becoming more stringent day by day. In this paper, a novel air-cycle refrigeration system has been designed and also tested for passenger vehicle applications. Automobile industry in developed countries has pivoted to R1234yf refrigerant for the most part, and has also rolled out R744 refrigerant for mass production to limited extent, which are in much lower Global warming potential (GWP) range than R134a.

Unfavorable climates, fatigue, safety & deprived sleep of driver’s leads to use of AC system for their quick thermal comfort during night with engine ON. This scenario is very critical from a human’s safety & vehicle functionality point of view. This also consumes an additional 10-15% of fuel requirements in AC running conditions. So, to address the social problems of driver’s sleep and pollution-free environment by reducing the use of fossil fuels, there is a need for alternative techniques for air cooling which work during engine OFF condition. Various alternative options for air cooling have been reviewed. Accordingly, the packaging flexibility of phase change material (PCM) technology makes it easy to implement, yet effective usage of large quantity stored PCM, needs optimization. This paper proposes a design of a hybrid air conditioning system for sleeper commercial vehicles using a combined conventional compression and phase change material.

This paper explains about the design & development of IHX for HCVs segment and vehicle level validation to get the actual benefits with this technology. Moreover, the data observed during vehicle testing also indicates the improvement in AC System Performance. This experiment was done on HCV platform vehicle with multiple actual test conditions with two designs of IHX. Final result shows the optimized AC system design to achieve better efficiency.

This paper summarizes the approach towards the process of computational simulation of the intake system and its experimental investigation. It is an important aspect to improve breathing of the diesel engines for performance, torque smoothening and emissions. This can be achieved by optimizing intake system parameters such as plenum volume, diameters, length of ports & runners, etc., which directly correlates the volumetric efficiency, thereby the performance of the engine. Keeping the objective of improving volumetric efficiency to achieve low-end performance, the intake system design optimization has been done on a twin cylinder, four cycle, compression ignition, In-Direct Injection (IDI) engine. For the simpler intake system, the primary pipe length & diameter can be calculated by mathematical formula applying Helmholtz Resonator principle. But, for a complex intake system, simulation software is used here.

Simultaneous reduction of NOx and PM from engine exhaust of a diesel engine is an interesting area of research due to the implementation of stringent emission regulations all over the world. Cost involved in expensive after treatment systems such as DPF and SCR necessitate minimization of engine out pollutants. With minimum engine out emission achieved through engine hardware and combustion parameter optimization, possibility of elimination or downsizing of the after treatment system can be explored. The paper presents the effect of fuel injection parameters and EGR rate on exhaust emission of a boosted diesel engine. Effects of parameters such as rail pressure, pilot-post injections, SOI, EGR rate and EGR temperature on a 4 cylinder two valve direct injection diesel engine is studied. Present study reveals the possibility of elimination of after treatment systems at BS IV level with optimization of engine hardware and combustion parameters.

Hybridization with engine downsizing is a regular trend to achieve fuel economy benefits. However this leads to a development of new downsized engine which is very costly and time consuming process, also engine downsizing demands for expensive higher power electric system to meet performance targets. Various techniques like gear ratio optimization, reducing number of gears, battery size and control functionalities optimization have been evaluated for maximum fuel economy keeping system cost very low and improving vehicle performance. With optimized gear ratios and reduced number of gears for parallel hybrid, it is possible to operate the engine in the best efficiency zones without downsizing. Motor is selected based on power to weight ratio, gradient requirements, improved acceleration performance and top speed requirement of vehicle in EV mode.

In hydraulic power assisted steering (HPAS) system higher steering oil temperature can cause deterioration of oil reservoir, thermal failure of pump/valves and can diminish system performance. Thermal analysis is performed for HPAS system architecture development in order to maintain steering oil temperature within design limits for optimal performance & increased life of HPAS steering system. In present study mathematical model of HPAS system consisting of steering pump, flow and pressure control mechanism, rotary valve, steering circuit pipes and hoses, thermal interaction with ambient is developed. The model is able to predict steering torque-hydraulic pressure dynamics of HPAS system as per design. Developed HPAS system model is integrated with steering kinematic and uniquely developed tire-road contact patch sliding model for estimating non-linear rack force behavior at higher steering angle.

Present stringent emissions norms; global fossil fuel energy scenario and competitive automotive market has driven many researches on diesel engine combustion in both academic and industry level. This work is an effort to improve the fuel economy without compromising emissions level of typical six cylinders inline CRDI diesel engine using optimized multiple injection strategy. There was some unusual nature of BSFC (Brake specific fuel consumption) observed on such typical engine. Also, Torque curve was not up to the mark for better drivability. This engine is equipped with most familiar in cylinder NOx reduction device namely EGR and multiple injections. There were few experiments conducted on same engine to optimize the BSFC using different multi injection strategies in line to marginal change of injection timing with respect to crank angle. Total exercise was done following partial Design of Experiments (DOE). EGR % has kept unaltered.

The automotive industry is facing a challenge as efficiency improvements are required to address the strict emission norms which in turn requires high performance downsized, lightweight IC engines. The increasing demand for lightweight engine needs high strength to weight ratio materials. To meet high strength to weight ratio, castings are preferable. However due to strength limitations for critical crankshaft applications, it forces to use costly forgings such as micro alloyed forging steel and Martensitic (after heat treatment) forging steel. To reduce the cost impact, high strength Austempered Ductile iron (ADI) casting is developed for crankshaft applications to substitute steel forgings. Austempered Ductile Iron is having an excellent mechanical properties due to aus-ferritic structure. The improved properties of developed ADI Crankshaft over steel forged crankshaft offers additional weight advantage.