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Global climate change is a major concern worldwide and most refrigerants which are being used today are Hydro-fluorocarbon (HFC), which are potent green house gases. With the rising popularity of electric vehicles, there has been an increased demand for effective and efficient cooling system, not only for cabin cooling for bus but for battery pack Thermal Management Systems also. This has led to an increase in the refrigerant amount and it is even more in case of commercial electric vehicle. Alternate refrigerant with low global warming potential like R1234yf (GWP = 4), Co2 (GWP = 1), R- 152a (GWP = 124) emerged to cater this challenge; But due to their high cost, risk regarding flammability and relative performance, some researchers found secondary loop cooling system as the next possible solution.

Air-conditioning and Refrigeration systems are widely used in many industries for cooling and preservation, and the evaporator is a crucial component responsible for heat absorption. The choice of refrigerant has a significant impact on the evaporator's performance, affecting the overall efficiency of the system. This paper investigates the effect of three common refrigerants, R134a, R407c, and R1234yf, on evaporator performance. A comparative analysis was performed using the conventional air-conditioning system consisting of a compressor, condenser, expansion valve, and evaporator. The evaporator performance was evaluated based on the cooling capacity, Refrigerant Side Pressure Drop (RSPD) and Superheat (SH). The results show that evaporator has highest cooling capacity with R134a, followed by R407C and R1234yf. In comparison to R134a, R1234yf had the lowest refrigerating effect followed by R407C.

Electric vehicles (EV) have become very significant and potential way to reduce greenhouse gas emissions on a worldwide scale. EV also provides Energy security, as it reduces the dependency on petroleum producing countries of the world. Similar to the conventional Internal Combustion Engine Cars, in Electrical Vehicles also the efficient air conditioning system is very important for providing thermal comfort and for giving safe driving conditions. In Air Conditioning systems for EV, the heating option is available in the form of Electrical heaters and Heat Pump systems. The Heat pumps have become more popular compared to the electrical Positive Temperature Coefficient (PTC) heaters because of their highly efficient and energy saving designs. However, there are still some issues with using heat pumps. One of such issue is their less Coefficient of performance (COP) at low ambient conditions.

The automotive industry is a gigantic industry as millions of vehicles are running on the road and it’s growing at a rapid rate. The emissions are causing various global problems such as global warming, green house effects, air pollutions etc. due to the use of fossil fuels in abundance. This drives to think for alternative solutions, which are eco-friendly and having less or no emissions. The electric vehicles (EVs) are the most reliable solution as it is having high performance and efficiency with zero emissions. The evolution of EVs has fuelled the two-wheeler EVs industry to flourish at a fast pace. Li-ion battery and traction motor are the most important components in two-wheeler EVs and the thermal management for battery is more important for higher efficiency with longer life and better reliability along with the traction motor to have long range and better durability.

In electric vehicles, along with cooling and heating requirement of battery, cabin atmosphere also need to be controlled according to human comfort level. Productivity level of humans decreases when cabin’s environment (including temperature, relative humidity and air velocity) varies too far from comfort range. For cold ambient conditions, waste heat from internal combustion engine is enough for heating passenger cabin in conventional vehicles. In contrast to that, electric vehicles do not have enough waste heat available to warm up cabin atmosphere during winters. Using battery power for heating in winters reduces vehicle mileage drastically. Consequently, many alternative cabin heating technologies and their combinations are proposed and designed to reduce the dependency on battery energy to improve thermal comfort under cold weather conditions.

The rapid evolution of electric vehicles (EVs) has considerably forced the automotive industry to design compact and highly efficient heat exchangers due to low-temperature applications. The plate type heat exchanger (Also known as “Chiller” in automotive industry) is one of the most important components in EVs thermal management systems. It is a type of heat exchanger, which uses metallic plates arranged like a staggered sandwiched structure and brazed together to exchange heat between two working fluids. The heat transfer between the plates occurs due to highly compact structural design as compare to any conventional heat exchangers. The chiller is having very large surface area, which is exposed to the working fluids as the distribution happens all across the plates. The chillers are more suitable design for transferring heat between ranges of working fluids pressure varying from low to high. Various types of welded, semi-welded plate heat exchangers are available in the market.

The thermal heat load requirement for the cabin and the cockpit of aerial vehicle varies with various conditions comprises of altitudes and different weather conditions. The mapping of the heat load w.r.t. the above conditions is a complex phenomenon, which involves difficult mathematical modeling. The aerodynamic design of the aerial vehicle allows the flow of ambient air to contribute in the cabin and cockpit heat load along with passengers, pilots & co-pilots heat load at various weather conditions. The current study considers the mathematical modeling of the cabin and cockpit of aerial vehicle w.r.t. various weather conditions and altitudes and simulate the heat load requirements. The estimation of the heat load plays a key role in thermal management systems of the aerial vehicle for both the cabin and cockpit. The objective of this study is to highlight the importance of heat load requirement of the aerial vehicle and methods to simulate it.

Radiators are types of heat exchangers, which are used to transfer the heat from one fluid to another fluid. It is mainly used in automobile engine cooling systems and the radiators are the major source of heat rejection from the system by cooling the working fluid (generally water or glycol mixture). The application of radiators in the two-wheeler vehicle segment plays a vital role in increasing engine efficiency by maintaining the optimum temperature inside the engine assembly. As the technology advances with higher power requirements for the two-wheeler vehicle segment, thermal management of combustion engine becomes a critical part of it, resulting in the advancement of radiator technology in terms of compactness and thermal performance. In order to cater to the increasing demand for high-powered engines, performance optimization of two-wheeler radiators becomes an important aspect of design.

High vehicle emission resulting in increasing the air pollution day by day has challenged and forced the automotive industry to look for alternate and more environment friendly technologies. The transformation of the automotive industry in near future towards green energy solutions has also fuelled the technological advancement in this industry. In order to fulfil this requirement, Electrical Vehicles (EVs) have emerged as the best solution available till now. It has become very popular because of the zero emission and higher wheel-drive efficiency. The vehicle has some limitations in terms of performance, cost, lifespan & battery safety. The EVs have lithium ion batteries incorporated to cater the drive power requirement. In order to maximize the vehicle performance, thermal management of the batteries becomes very critical. The battery thermal management system (BTMS) has crucial role in controlling the thermal behaviour of the batteries.

Recently, the use of air conditioning systems is growing rapidly due to increasing global temperatures. Considering enormous growth in the application of the air conditioning system, there is an urgent need to improve design, performance, and efficiency thereof. For example, the air conditioning systems that are being used these days are required to provide improved efficiency per unit of power consumed, and they are also required to have a smaller form factor as compared to conventional air conditioning systems. Therefore, a lot of modern air conditioning systems employ components such as internal heat exchanger, thermal expansion valves and forth to improve their performance while having a small form factor.

Compact heat exchangers are extensively used in the automotive sector especially in engine cooling and passenger cabin cooling systems. Considering the evolution of compact heat exchangers from the past several years, development on the compactness has grown up rapidly with the market demand. In line with the futuristic view, it has become mandatory to optimize their thermal performance along with compactness, manufacturing feasibility and durability requirement. The present work investigates the cumulative impact of various geometrical parameters of tube & fin design on heat transfer coefficient and pressure drop. The parametric study determines the most optimized core matrix by considering the manufacturing constraints using the mathematical & analytical modeling. The system is mathematically modeled and then simulated to estimate the heat transfer rate, weight, free flow area, wetted area, etc.

In recent times, overall thermal comfort and air quality requirement have increased for vehicle cabin by multifold. To achieve increased thermal comfort requirements, multiple design innovation has happened to improve HVAC performance. Most of the advance features like multizone HVAC, dedicated rear HVAC, Automatic climate control, advance air filters, and ionizers etc. lead to increase in cost, power consumption, weight, and integration issues. Besides this in the vehicle with only front HVAC, airflow is not enough to meet rear side comfort for many cars in the B/C/SUV segment. This study aims to analyze the various parameters responsible for human thermal comfort inside a car. The focus of study is to use light weight, low power consumption, compact Rear Blower to provide passengers comfort by providing optimum airflow inline of mean radiant temperatures and cabin air temperature.

The aim of this paper is to highlight the unique requirement of air conditioning systems for very high ambient temperature and dusty environment. Typical requirement of such applications is needed for off road vehicles, tractors, railway etc. Among them the system requirement for railway has its own challenges in terms of performance, reliability and serviceability. In one of such applications existing design of air conditioning system was facing the issue of frequent tripping during the peak summer condition. One of the reasons was very high dust environment around its condenser area. The level of dust was so high that mesh filter was deployed at condenser front area to prevent choking of condenser fins heat transfer area. The condenser filter cleaning was needed on daily basis to run the Air Conditioning (AC) properly. To solve this problem a newly designed multi-flow wave fin type condenser was deployed in place of regular multi-flow louver fin condenser.

With stringent requirements of fuel efficiency and emissions, the airflow and thermal management within the under-hood environment is gaining significance day by day. While adequate airflow is required for cooling requirements under various vehicle operating conditions, it is also necessary to optimize it for reduced cooling drag and fan power. Hence, the need of the day is to maximize cooling requirements of Condenser, Radiator, CAC and other heat exchangers with minimal power consumption. To achieve this objective and due to the complicated nature of 3D flow phenomenon within the under-hood environment, it is useful to perform 3D CFD studies during preliminary stages to shorten design time and improve the quality and reliability of product design. In this paper we present the results from a CFD under-hood analysis that was carried out for design, development and optimization of a CRFM (Condenser, Radiator and Fan Module).