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In today’s competitive scenario, the automotive product life cycle has drastically reduced and all Auto OEM’s are coming up with their updated products with lesser development time. These frequent product upgrades are possible due to use of various digital tools during product design and development. Design and optimization of engine coolpack (powertrain cooling unit) to attain engine cooling performance is one of the important parameter during vehicle development or upgrade. Hence, to keep control over development cost and time of delivery, quick and accurate digital validation capability like one dimensional (1D) simulation is the need of the hour. To predict the powertrain cooling (PTC) performance at vehicle concept stage, when physical prototypes are not available, airflow data from similar developed platforms is considered as an input for 1D simulation.

The growing demand of fuel and cost saving on vehicle, today’s vehicle manufacturer are working on various weight reduction initiative in EV. Lighter weight vehicle have bigger challenges to meet NVH requirement. There are two types of EV called modified and adopted EV’s are commonly in use. The sub frame type of EV system comes under the category of modified EV. In this paper, a mounting system is studied and compared for a cradle type EV as well as sub frame or saddle type EV. MATLAB based optimization tools are used for parameter optimization. The focus is put on the optimization of mounting system location and stiffness for energy optimization, CoG and TRA-EA optimization. The best engine mounting system is compared and adopted based on simulation. 12 DOF studied to address high frequency resonance issues for a sub frame type EV. Finally robustness of the system is checked based on various simulation and optimization.

In present day passenger cars, Mobile Air Conditioning (MAC) system is one of the essential features due to rise in overall ambient temperatures and comfort expectation of customers. During the development of MAC system, the focus is on cooling capacity of system for maintaining in-cabin temperatures. However, parameters like solar radiation, air velocities at occupant, relative humidity, metabolic rate and clothing of occupants also influence occupant’s thermal comfort and normally not considered in design of the MAC system. Subjective method is used to evaluate thermal comfort inside vehicle cabin which depends mainly on human psychology. To better understand the effect and minimize the human psychological factors a large sample of people are required. That process of evaluating the comfort inside the vehicle cabin is not only time consuming but also impractical.

In the modern era of automotive industry, occupant comfort inside the cabin is a basic need and no more a luxury feature. With increase in number of vehicles, the expectations from customers are also changing. One of the major expectations from real world customers is quick cabin cooling thru all seasons, particularly when the vehicle is hot soaked and being used in summer conditions. Occupant thermal comfort inside the vehicle cabin is provisioned by a mobile air conditioning (MAC) system, which operates on a vapor compression-based cycle using a refrigerant. The main components of a direct expansion (DX) based MAC system are, a compressor, condenser, evaporator, and expansion valve. Conditioned air is circulated inside the cabin using a blower, duct system and air vents. The AC condenser is the most critical component in AC circuit as it rejects heat, thereby providing for a cooling effect inside the cabin.

Steering system deliver a precise directional control to the vehicle chassis and ensure the safe driving at all maneuvers. Hydraulic power assisted system (HPAS) helps drivers to steer by boosting steering assistance of the steering wheel while retaining the road feel. HPAS performance is associated with the design characteristics of rotary valve, steering, suspension, kinematics, brake, tire, vehicle speed and load transfer. Thus a detailed power steering system model is absolutely necessary to evaluate and optimize the performance characteristics. However, many components of HPAS system are proprietary in nature so it is very challenging to get component characteristic of each sub-system for the complete power steering system model. Hence, it is very important to establish a technique to extract all such influencing characteristics with available test facility.

Today urban buses are equipped with more air consuming devices for an example pneumatic doors, exhaust brake, air suspension and in SCR system to name a few. This has resulted in higher air demand leading to high compressor duty cycles which cause conditions (such as higher compressor head temperatures) that may adversely affect air brake charging system performance. These conditions may require additional maintenance due to a higher amount of oil vapor droplets being passed along into the air brake system. Factors that add to the duty cycle are air suspension, additional air accessories, use of an undersized compressor, frequent stops, excessive air leakage from fittings, connections, lines, chambers or valves, etc. This paper discussed about methodology used to reduce air consumption of air consuming devices used in urban bus application. Performance assessment of air consuming devices with minimum available air pressure was conducted and found satisfactory.

Vehicle Ergonomics is one of the most vital factor to be considered in vehicle design and development, as the customer wants a comfortable and performance oriented vehicle. An uncomfortable driving posture can lead to painful driving experiences for longer hauls. The control pedals viz. Accelerator, Brake and clutch pedal (ABC Pedals), are the most frequently used parts in the vehicle, their proper positioning with respect to human anthropology is of prime importance, from driver comfort viewpoint. The methodology currently used for optimizing ergonomics with respect to the positioning of pedals in a vehicle included; measuring anthropometric angles manually with the help of H-Point Machine, subjective jury analysis and through software like RAMSIS, JACK, etc. Manual measurement doesn’t give the flexibility of iterations for optimization. The subjective analysis is based on insinuations thereby, cannot be standardized.

Vehicles subjected to Indian duty cycles have to undergo extreme environments & road terrains, stone chipping. Underbody wear from this is one of the most significant forms of deleterious corrosion. Automobile companies deal with this by going for exotic & expensive underbody coating, which compositionally are "Polyvinyl Plastisol also popularly known as Poly Vinyl Chloride (PVC)". Across automotive industry, the stone chipping is prevented via applying PVC-coating to the extent of 800-1000 microns. The application of PVC-material throughout the vehicle underbody will add approximately 8-12 Kgs of weight. Our objective was to reduce the weight of applied PVC-material.

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.

BSR noise is an important parameters for customer discomfort. According to a market survey, squeaks and rattles are the third most important customer concern in cars after six months of ownership. The high quality acoustic environment of a car, annoying noises like buzz, squeak, and rattle is related to various parameters such as material assembly, tolerance, aging, humidity, surface contact, and surface hardness. BSR is originated from frictional movement between two parts or from the impact between two parts. The rattle noise is caused when surfaces close to each other move perpendicular to each other due to insufficient attachments or insufficient structural strength. In our study, we have shown the impact of various front suspension component in front suspension assembly on BSR noise and also the method to detect and attenuate the same. A methodical analysis process is shown to identify the contributing part and resolve the BSR issue.

In the past five years, Indian cities have been consistently appearing in the list of top 15 world’s most polluted cities. Every day, a common man in India spends more than 2 hours on the road due to numerous reasons, thus exposed to inhale highly polluted air. Further, the passenger car users is exposed to ~ 6 times more polluted air as compared to ambient air reason being the air is recirculated through the air conditioning system. Prolonged exposure to such polluted/ recirculated air shows increasing trend in respiratory illnesses, breathing discomfort and fatigue. This paper discusses the key challenges involved in incorporating cabin air filter as cabin air quality enhancer in current mobility solutions.

This paper quantifies and compares the cooling performance and refrigerant and fuel cost savings to automobile manufacturers and owners of secondary-loop mobile air conditioners (SL-MACs) using refrigerants hydrofluorocarbon (HFC)-134a and the available alternatives HFC-152a and HFO-1234yf. HFC-152a and HFO-1234yf are approved for use by the United States Environmental Protection Agency (US EPA) and satisfy the requirements of the European Union (EU) F-Gas Regulations. HFC-152a is inherently more energy efficient than HFC-134a and HFO-1234yf and in SL-MAC systems can generate cooling during deceleration, prolong comfort during idle stop (stop/start), and allow powered cooling at times when the engine can supply additional power with the lowest incremental fuel use. SL-MAC systems can also reduce the refrigerant charge, emissions, and service costs of HFO-1234yf.

With the introduction of Connected Vehicles, it is possible to extend the limited horizon of vehicles on the road by collective perceptions, where vehicles periodically share their information with other vehicles and servers using cloud. Nevertheless, by the time the connected vehicle spread expands, it is critical to understand the validation techniques which can be used to ensure a flawless transfer of data and connectivity. Connected vehicles are mainly characterized by the smartphone application which is provided to the end customers to access the connectivity features in the vehicle. The end result which is delivered to the customer is through the integrated telematics unit in the vehicle which communicates through a communication layer with the cloud platform. The cloud server in turn interacts with the final application layer of the mobile application given to the customer.

Brake system design is intended to reduce vehicle speed in a very short time by ensuring vehicle safety. In the event of successive braking, brake system absorbs most of vehicle’s kinetic energy in the form of heat energy, at the same time it dissipates heat energy to the surrounding. During this short span of time, brake disc surface and rotor attains the highest temperatures which may cross their material allowable temperature limit or functional requirement. High temperatures on rotor disc affects durability & thermal reliability of the brake rotor. Excessive temperature on brake rotors can induce brake fade, disc coning which may result in reduced braking efficiency. To address the complex heat transfer and highly transient phenomenon during successive braking, numerical simulations can give more advantage than physical trials which helps to analyze complex 3D flow physics and heat dissipation from rotors in the vicinity of brake system.

An automotive radiator cooling fan has been observed to be an important noise source in a vehicle and with increasing noise refinements, the need for a quieter but effective fan is of utmost importance. Although some empirical prediction techniques are present in literature, they are not sufficiently accurate and cannot give a detailed view of the entire noise spectrum and the various noise prone zones. Hence the need for highly accurate Computational Fluid Dynamics (CFD) study is essential to be able to resolve the minute acoustic stress. Large Eddy Simulation technique in CFD is used to resolve the minute scales of motion in the flow as the sound pressures simulated are very small compared to system level pressures and require immense accuracy. Detailed mesh dependency and Y+ studies are conducted to implement higher accuracy as well as keep mesh requirements within computationally feasible zone.

For sustainability, industries are now focusing on methodologies for Recycle, Reuse, Repair of a variety of industrial material. Cutting tools used in manufacturing of automobiles have therefore become a part of it. There are many ways in which cutting tools can be recycled. Be it by reshaping a used up throwaway type tool [1] or by redesigning a tool holder for the use of unused cutting edges [2]. An automobile part was redesigned for reuse of a used up tool [3]. By reforming, very large size grinding wheel used for crankshaft grinding can be reused after it gets smaller in diameter during crankshaft grinding operation [4]. This paper deals with two more implemented ideas to show that with a redesigned tool holder it was possible to reuse used up carbide inserts and significantly cut the manufacturing cost in addition to avoid manufacturing of new inserts and thus conserve natural resources.

Vehicle aerodynamic design has a critical impact on fuel efficiency of the vehicle. Reducing aerodynamic wind resistance of the vehicle's exterior shape and reducing losses associated with requirements for engine compartment cooling through vehicle front openings plays key role in achieving desired aerodynamic efficiency. Today fairly large number of computational fluid dynamics (CFD) simulations are being performed during the vehicle aerodynamic design and development process and it is rapidly increasing day by day. Vehicle aerodynamic design and development process involves mainly aerodynamic shape development, aerodynamic optimizations of vehicle external components (side view mirror, spoilers, underbody shield etc.) and number of” what if studies during preliminary design process. Licensing costs of the available commercial CFD simulation solver has significant impact on product development cost when numbers of aerodynamic simulations expand.

Single plate dry clutch is most commonly used in automotive transmission. This paper proposes a unique approach of modelling a single plate dry clutch in Simulink and Simscape simulation environment. Clutch model is divided into two subsystems as translational and rotational. The translational system is linear system of diaphragm and cushion spring as a two-degree freedom system. Nonlinearity of the diaphragm and cushion spring has been modelled based on experimental data. This enables to simulate friction torque variation during clutch engagement. In rotational system, frictional torque generation between flywheel-clutch disc and pressure plate-clutch disc has been modelled separately. This novel approach of developing separate friction models helps in understanding variation in torque carrying capacity due to rise in the temperature of the friction pads because of frictional and engine heat.

EU directive 2005/64/EC on type approval of motor vehicles with respect to their Reusability, Recyclability and Recoverability ( RRR ) requires vehicle manufacturers to put in place the necessary arrangements and procedures for Parts, Materials and Weight (PMW ) data collection from full chain of supply. This is required to perform the calculations of recyclability rate and recoverability rate in line with ISO 22628. Commonly practiced data collection methodologies included spreadsheet and use of internationally available IT support system for collection of material data. Data complexity and prohibitive cost for using Internationally available IT Support systems like IMDS (International Material Data System) has led to the in-house development of IT enabled Solution customizing Siemens PLM software product (Team centre Enterprise) and SAP (SRM suite).

Vehicle aesthetic appearance is critical factor in the perceived quality of a vehicle. Auto OEM focuses on the improvement of perceived quality. The perceived quality of a vehicle is improved by achieving a superior finish on the visible parts. Plastic parts used in visible areas are painted to achieve a superior finish & aesthetic. However, the painting process is very energy intensive, releases a lot of harmful VOCs into the environment, emits carbon di-oxide into the environment & is a very costly process. Also, painted parts pose a challenge for recycling at the end of life. For painting one square meter area, around 6.5 Kg of co2 is released. Additionally, the painting cost contributes to around 60 % of the part cost. As the emphasis has increased on sustainability & reducing the cost, we took the challenge to develop novel mold in color material to eliminate the painting process without compromising the aesthetic & functional requirements of part.