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In India, around 70 million people travel by public transport buses. With rising air pollution across cities, there is a need to safeguard passengers from inhaling polluted air. Contaminants in such polluted air could be fine to coarse dust (2.5 micron to 100 micron), exhaust gases (oxide of sulphur, nitrogen and carbon), total volatile organic compounds, bacteria and viruses arising out of covid-19 pandemic. Passengers commuting in buses are continuously inhaling air that is re-circulating through the Air Conditioning system (AC) and also comes in contact with multiple co-passengers and touch points. This air potentially carries a high dose of contaminants and inhalation of such air can lead to health issues. Vehicle manufacturers intend to provide clean air inside the vehicle cabin by configuring various Air Purification systems (AP) which reduce air contaminants in the closed space of a cabin.

Mobile Air Conditioning (MAC) system provides year round thermal comfort to the occupants inside vehicle cabin. In present scenario, 1D CAE simulation tools are widely used for MAC system design, component sizing, component selection and cool down performance prediction. The MAC component sizing and selection mainly depends on cooling load which varies with ambient conditions, occupancy, cabin size, geometry and material properties. Therefore, detailed modeling of vehicle cabin is essential during MAC system digital validation as it helps to predict performance across wide number of contributing factors. There are two different methods available in 1D Simulation for vehicle cabin modeling, viz. ‘simple cabin’ and ‘advance cabin’. With the simple cabin modeling approach, vehicle cabin is modelled as a group of lumped masses, which only enables prediction of average vent and average cabin temperatures. In advance cabin modeling approach, vehicle cabin is modelled more comprehensively.

The interior components of a passenger vehicle are designed to provide comfort and safety to its occupants. In the event of accident, vehicle interiors are primary source of injuries when occupants interact with them. Vehicle interiors consists of Instrument panel (IP), center console, seats and controls in front of seating position etc. Severity of the injuries depends on the energy dissipating characteristics, profiles, projections of different interior components. These are assessed by ECE R21 and IS12553 head form impact tests. To evaluate the Head form impact performance on Interior components, Computer Aided Engineering (CAE) simulations are extensively used during the vehicle development. In order to predict failure of plastic components and snap joints which might lead to expose sharp edges, it is critical to model plastic material and snap joint.

Energy efficient HVAC System is getting a significant attention from the automotive industries. By reducing environmental thermal load, it is expected to achieve a vehicle climate control system that requires less AC power on a vehicle while maintaining the occupant thermal comfort. In order to accomplish this, several technologies to reduce the environmental thermal load are required that includes a glazing system with solar reflecting glasses, highly effective thermal insulation materials, and vehicle interior weight reduction strategies. The structure of a vehicle can absorb a significant amount of heat when exposed to hot climate conditions. 50-70% of this heat penetrates through the glazing and raises both the internal cabin air and the interior trim surface temperature [1].

In recent years, car manufacturers have been working intensively on new ways to improve the quality of interior trims. Elimination of squeak and rattle has become one of the main concerns for car manufacturers lately, given the significance of these incidences in customers' perception of overall quality. Traditionally, rattle problems are found and fixed with physical tests at the late design stage, mainly due to lack of up-front CAE simulation prediction methodology and tools availability. This article presents a finite element based methodology for the improvement of rattle performance of a vehicle tailgate. In this study, appropriate finite element (FE) modeling technique was introduced to accurately predict occurrence of tailgate rattle. Simulation process using commercial software “Nastran” employing modal and forced frequency response analyses was illustrated. Design modifications were incorporated for performance improvement of rattling on present and future SUVs.

The current paper focuses on the compact HVAC component development for electric passenger vehicles running in countries where the external ambient conditions are harsh. Various previous studies have shown that the energy required for HVAC system alone is about 12-15 percent of the overall vehicle energy demands. Due to very high thermal loads, the Electric Vehicles operating in such countries will obviously fall under the higher HVAC energy consumption band. In addition to the energy demand, the cooling requirements like shorter pull-down time adds further challenges to the HVAC design. Another major challenge being faced by the EV manufacturers is the concerns due to range which has resulted in compact vehicles having less space for HVAC and other subsystem components. The current paper proposes an approach for replacing the conventional air-cooled condenser by liquid-cooled condenser. A liquid-cooled condenser will be much more compact than a conventional condenser.

Commercial electric vehicle air conditioning system keeps occupants comfortable, but at the expense of the energy used from the battery of vehicle. Passengers around the world are increasingly requesting buses with HVAC/AC capabilities. There is a need to optimise current air conditioning systems taking into account packaging, cost, and performance limits due to the rising demand for cooling and heating globally. Major elements contributing to heat ingress are traction motor, front firewall, windshield & side glasses and bus body parts. These elements contribute to the bus’s poor cooling and lack of passenger comfort. This topic refers to the reduction of the heat ingress through usage of different glass technology like IR Cut & solar green glass with different types of coating.

Safety and Comfort are the core requirements of the automotive seating systems. Number of the occupants, determines type of the seating system requirement. The second row seat often needs to fold and slide, to allow the passenger to enter inside the car. Folding second row seat will also allow accommodating larger length cargo. The over folding of seat is controlled by hard stop mechanism. The hard stop mechanism generally consists of the seat arm stopper at back seat and hard stop located at base of the seat. These stoppers will limit the further motion of back seat. The folding speed of back seat is governed by various factors e.g. adjacent seat foam/structure friction, location, structural mass of seat etc. The scope of the paper is to evaluate various folding speeds of the back seat. Its effects are evaluated for the stresses and fatigue life of the hard stop components.

The structure of a vehicle is capable of absorbing a significant amount of heat when exposed to hot climate conditions. 50-70% of this heat penetrates through the glazing and raises both the internal cabin air temperature and the interior trim surface temperature. When driving away, the air conditioning system has to be capable of removing this heat in a timely manner, such that the occupant’s time to comfort will be achieved in an acceptable period [1]. When we reduce the amount of heat absorbed, the discomfort in the cabin can be reduced. A 1D/3D based integrated computational methodology is developed to evaluate the impact of vehicle orientation on cabin climate control system performance and human comfort in this paper. Additionally, effects of glazing material and blinds opening/closing are analyzed to access the occupant thermal comfort during initial and final time AC pull down test.

Enriched ventilation and driver assistance systems which plays vital role in human thermal comfort and safety, are now necessities for the whole automotive sector. For faster cabin thermal comfort, air circulation around occupant’s body reveals higher cabin comfort index. In India natural and forced ventilation system is predominantly used in commercial vehicles as an economical solution for achieving interim cabin comfort over air conditioning system. Presently used forced ventilation system consist of electrically driven blower motor to remove stale air around human body which is adding alternator load and thus affects fuel economy. Remarkably, 22% of such auxiliary electrical load is taken by electrical components from engine generated power. In order to enhance cabin thermal comfort and conceivably reduce power usage, an effective air flow control system is need of hour.

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.

Downsizing is one of the crucial activities being performed by every automotive engineering organization. The main aim is to reduce - Weight, CO2 emissions and achieve cost benefit. All this is done without any compromise on performance requirement or rather with optimization of system performance. This paper evaluate one such optimization, where-in radiator assembly with two electric fan is targeted for downsizing for small commercial vehicle application. The present two fan radiator is redesigned with thinner core and use of single fan motor assembly. The performance of the heat exchanger is tested for similar conditions back to back on vehicle and optimized to get the balanced benefit in terms of weight, cooling performance and importantly cost. This all is done without any modification in vehicle interface components except electrical connector for fan. The side members and brackets design is also simplified to achieve maximum weight reduction.