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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.

The Indian continental region encompasses various geographical terrains and climatic conditions, which necessitates automotive OEMs to build robust cabin climate control systems that ensure year round occupant comfort. Such systems comprise of, an on-board Heating Ventilation Air Conditioning (HVAC) sub-system and a control head (manual or automatic) that works as a user interface for adjusting parameters such as airflow, temperature and air directivity best suited to the occupants. In case of passenger cars, the on board HVAC system primarily serves two major purposes. To provide year round thermal comfort to the passengers and to enable defogging and defrosting action of front and rear windshield as per regulatory requirements and customer needs particularly for enhancing visibility in cold and humid ambient conditions.

Automotive exterior lighting systems has to meet several regulatory requirements & manufacture specific internal standards to achieve desired performance. These test specifications are usually generic in nature and formulated mainly to validate the standalone product under standard laboratory conditions. Most of the time these specifications are common for entire vehicle portfolio. The rationale of these standards is to define the basic illuminance in the safe braking distance. Thus, however, using the requirements in these standards to evaluate the performance of front lighting systems is only qualitative. Research on working out method for quantitative evaluation of front lighting system is necessary [1] In practice, however, the luminance levels at road surfaces are usually very dynamic; depend largely on the variations in vehicle parameters, ambient weather conditions, road surface uniformities and effects of light intensity & color contrasts on target visibility.

Self-soiling or surface contamination is usual phenomenon observed during rainy season wherein dirt on road are picked by rotating wheel and later released in air as fine particles. These released dirt particles are further carried by airflow around vehicle and as a result stick on vehicle exterior surfaces leading to surface contamination. Surface dirt contamination is one of critical issues that need consideration during early phase of vehicle development as vehicle styling plays a critical role for airflow around vehicle and therefore settling of dirt on vehicle exterior surfaces. Non consideration of such aspects in design can lead to safety issues with likely non-functioning of parking sensors, camera and visibility issues through ORVM, tailgate glass etc. Hence it is important to understand physical as well as digital techniques for assessment of vehicle for surface dirt contamination.

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.

This paper highlights the transition of multi-axis suspension test rig from fixed reacted type to semi-inertial type and the benefits derived thereof in simulation accuracies. The critical influence of ‘Mx’ and ‘Mz’ controls on simulation accuracies has been highlighted. The vital role of ‘Mz’ control in the resonance of wheel pan along ‘Z’ axis and thereof arresting unwanted failures modes in spindle has been duly emphasized. Finally, the role of constraints and boundary conditions on simulation accuracies has been demonstrated by replacing the reaction frame with vehicle body.

Electric vehicles are fast expanding in market size, and there are increasing customer expectations on all aspects of the vehicle, including its noise and vibrational characteristics. Irritable noise from traction motors account for around 15% of the overall noise in an electric vehicle, and thus, has a need to be analysed and studied. This study focuses on identifying the critical vibro - acoustic orders for an 8 pole PMSM (Permanent Magnet Synchronous Motor) for three cases - healthy, with static eccentricity and with dynamic eccentricity. PMSM motors are widely used for traction and other applications due to their higher power density along with compact size. A coupled approach between electromagnetic and vibro - acoustic simulation is deployed to characterise the NVH behaviour of the motor.

The small commercial vehicle business is driven by demand in logistic, last mile transportation and white goods market. And to cater these businesses operational and safety needs, they require closed container on vehicle. As of now, very few OEM’s provide regulatory certified container vehicle because of constrains to meet inertia class of the vehicle. This paper focuses on design of a durable and extremely reliable container, made of the low-cost economy class glass fibre & core material. The present work provides the means to design the composite container for the N1 category of the vehicle. The weight of after-market metal container ranges between 300-350 Kg for this category of vehicle, which affects the overall fuel economy and emission of the vehicle. A detailed CAE analysis is done to design composite container suitable to meet inertia class targets and to achieve weight reduction of 30-40% as compared to metal container.

Frame is one of the vital part of Light & Heavy Commercial vehicle which holds all the parts and testing the frame is not a cost effective as the complete vehicle assembly needs to be tested as the individual testing of frame is not formulated for testing. In the development stage of the vehicle we always seek for a quick, cost effective and reliable methodology so that any modification can be made by identifying the failures. In this paper we have addressed this problem by developing a generic frame test methodology by which the frame can be tested in the preliminary stage of development in a cost effective way and reliable way. The Multi Body Dynamics Simulation was carried out and rig was designed comprising of servo hydraulic actuators. The frame was instrumented to acquire the Field, Event and Torture track data for the formulation and verification of the synthetic drives.

The Indian automotive industry is going through a rapid transformation phase. Regulatory emission norms such as, migration from BSIV to BSVI engine, increased adoption of μ-hybrid, full electric and autonomous cars are examples of such rapid transformation. The upgradation of internal combustion engines for compliance with new regulatory norms (e.g., from BSIV to BSVI) has caused a significant change in the automotive acoustic performance. As the powertrain system are being upgraded and getting quieter, the on-board Heating, Ventilation and Air-Conditioning system (HVAC) system emerges as one of the prominent noise sources which strongly influences overall refinement levels inside the cabin. This in turns is affecting overall feeling of passenger’s comfort. The HVAC system of an automobile is a compact and yet a complex system designed to provide thermal comfort inside the car cabin.

Electric Vehicles (EVs) have started gaining notable attention from the industry and customers in India over last couple of years. However, OEMs are still cautious for wider customer acceptance of EVs as their products are challenged with expensive component costs, lack of charging infrastructure, issues of driving range anxiety amongst the customers. In such a scenario, OEMs are constantly looking for innovative solutions which will enhance the driving range of EVs by optimizing the power consumption in every possible way. In an electric vehicle, Heating Ventilation and Air Conditioning (HVAC) system is essentially required for providing all season thermal comfort and maintain operating temperature of High Voltage battery pack (HV battery). While catering to such requirements, HVAC system becomes one of the major power consuming aggregate in EVs.

With the advent of new technologies and rigorous research and development work going on vehicle engines, cars are becoming quieter and more refined than ever before. This has led to the observance of subjective noises being audible to passenger compartment which were earlier masked behind engine noise. The vehicle HVAC system has several moving parts and transient flow of refrigerant which can cause certain types of irritant noise. Thus having a refinement in of air-conditioning (AC) system would aid us in cutting down on this parasitic noise source. Thus noise refinement should be one of the important parameters during the design and development of the Heating, Ventilation and Air-Conditioning (HVAC) system for a vehicle program.

The automotive application places very special demands on the air conditioning system. As is the case with any other process, system efficiency is very important and the automotive air-conditioning application is no exception. While the characteristics of all the major components in the air conditioning system like compressor, condenser, evaporator and blower contribute to overall system efficiency, localized inefficiencies do play a part and so must be kept to a minimum, especially in this day and age when extra emphasis is being laid on sustainability. One such phenomenon that contributes to the system inefficiency is heat pick-up in suction line. Since the temperature at the evaporator-outlet is quite lower than ambient and also its surroundings (steering system pipes and hoses, engine, air intake pipes and so on), the refrigerant picks up heat as it moves along the suction line up to the compressor inlet. This heat pick-up is detrimental to the overall system performance.

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.

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.

In current days electric vehicles (EVs) are being promoted on significant scale through various government initiative as a zero-emission means of transport. However the major hurdle for wider customer acceptance of EVs are being comparatively expensive, lack of charging station infrastructure and ambient based limited driving range. It is known that Heating Ventilation and Air Conditioning (HVAC) system is major contributor in overall power consumption of electric vehicles. The HVAC system architecture and working logics in EVs are different from the one in fuel based vehicle.

Electric vehicles (EVs) carries two main anxieties in users which are its range and battery life, hence these are important parameters to be taken care of during electric vehicle development. Range of EV depends on many parameters such as vehicle weight, heating ventilation and air conditioning (HVAC) system, battery cooling system (BCS), traction cooling system (TCS) and other electrical loads, which consumes power from a High Voltage (HV) battery. Severe hot ambient in India requires a big size HVAC system, on the other hand, the battery pack needs refrigerated cooling system to keep its temperature in control. Hence, the major parasitic consumers in an EV are HVAC and BCS. In order to enhance the overall efficiency, a trade-off between these two systems is crucial, as both the systems are served with common compressor and condenser in dual loop refrigerant circuit.

In regions like Indian Subcontinent, Gulf or Saharan & Sub-Saharan Africa, where the sunshine is abundant almost all year round, air-conditioning is an important aspect of vehicles (passenger cars, buses etc.). Higher heat means higher cooling demand which in turn means bigger AC system. Like other auxiliaries, AC compressor is a parasitic load on the engine. The best way to beat heat and reduce cabin heat load is to stop heat build-up itself. The present paper explores one such means of reducing cabin heat build-up by leveraging latent heat properties of phase change materials and thus improving the air condition performance. With the help of a case study this paper aims at detailing comprehensive effect of phase change material (PCM) and its application on the heat build-up inside the cabin of a vehicle, the air conditioning cooling performance, the time required to achieve comfort temperature, work of compression performed by AC compressor and COP.

In an automotive air conditioning system, evaporator is well designed for effective heat transfer between refrigerant and air flowing over the evaporator. This cold and dehumidified air obtained at evaporator is then supplied to passenger cabin. There are various parameters like air flow over evaporator, ambient temperature, humidity condition and condensate drain mechanism which can cause frost formation over the evaporator core. This study presents the probable causes of frost formation and their effects on the performance of evaporator and thus affecting overall performances of the automotive air conditioning system. In this study effect of variation in four major independent factors such as poor response of thermistor, undercharged refrigerant system and overcharged refrigerant system, drop in air flow by blower due to clogged air-filter, and also the effect of type of compressor has been studied.