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Because electric vehicles (EVs) do not generate pollutants during usage, and they can potentially rely on energy provided by a selection of renewable sources, they are the focus of much current interest. However, due to the present capabilities of battery technology, the overall range of such a vehicle is limited. Furthermore, once the battery is depleted relatively long recharging times are currently required before the vehicle is available for use again. Extended range electric vehicles (E-REVs) overcome many of the short-comings of EVs by having a ‘range extender’ unit, which consists of an onboard electric generator powered by an internal combustion engine. In this type of powertrain, the engine configuration either used the spark ignition or compression ignition engines. The engine operation in cold-start conditions can have a significant impact on drivability, fuel economy and tailpipe emissions.

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].

The range of Plug-In Electric Vehicles (EVs) is highly influenced by the electric power consumed by various sub systems, the major part of the power being used for vehicle climate control strategies in order to ensure an acceptable level of thermal comfort for the passengers. Driving range decreases with low temperatures in particular because cabin heating system requires significant amount of electric power. Range also decreases with high ambient temperatures because of the air conditioning system with electrically-driven compressor. Both thermal systems reduce EV driving range under real life operating cycles, which can be a barrier against market penetration. 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.

During cabin warm-up, effective air distribution by vehicle climate control systems plays a vital role. For adequate visibility to the driver, major portion of the air is required to be delivered through the defrost center ducts to clear the windshield. HVAC unit deliver hot air with help of cabin heater and PTC heater. When hot air interacts with cold windshield it causes thermal losses, and windshield act as sink. This process may causes in delay of cabin warming during consecutive cabin warming process. Thus it becomes essential to predict the effect of different windscreen defrost characteristics. In this paper, sensitivity analysis is carried for different windscreen defrosts characteristics like ambient conditions, modes of operation; change in material properties along with occupant thermal comfort is predicted. An integrated 1D/3D CFD approach is proposed to evaluate these conditions.

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.