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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.

Vehicles wind shield are designed to provide a clear visibility in winter as its one of the most important requirement for the comfortable and safe journey. In extreme winters, wind shield of vehicle is covered with layer of ice and if frosted happened, results in reduces the visibility distance. To increase the visibility and providing the comfort to driving the vehicle, heater is used in vehicle as an integrated part of vehicle HVAC System. When the blower air passes through heater, air temperature gets increased. When the hot air is injected through grill at designed angle of injection and at selected air velocity on wind shield surface, ice on wind shield melting due to convection heat transfer phenomenon and thus achieved a clear windshield glass and clear visibility at driver and at co-driver area.

Heating, ventilation and air conditioning systems play a crucial role in our day-to-day activities. With rise in global warming, leading to climate change, HVAC unit is the need of the hour. With average temperatures on the rise, it is quite imperative that the unit provides better thermal comfort to the passengers. Off-road vehicles like tractor, is also no exclusion. Tractor drivers have to experience adverse weather conditions out in the open field. Thus it is quite fundamental that sufficient airflow reaches every point inside the driver cabin, ensuring proper cool-down. To ensure proper distribution of airflow inside the cabin, optimization of HVAC unit needs to be properly carried out. The present study shows how an HVAC of an off-road vehicle is properly optimized with the help of Computational Fluid Dynamics. STAR-CCM+ v2021.2.1 is used as solver for the simulation.

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 heating, ventilation and air conditioning system is one of the complex systems installed inside the cabin of an automobile vehicle. Each HVAC discipline has specific design requirements in terms of packaging space, performance targets, etc. Technical specifications such as airflow, noise, air distribution, allowable leakage rate vary as per vehicle segment and interior design accordingly. While maintaining the design parameters of HVAC, design engineers often face challenges related to water leakage, air leakage, water infiltration, etc. Controlling these parameters becomes crucial for customer satisfaction and for safety features. Several studies on seal proof technology have been conducted and continue to be conducted, whether for air-based applications, water-based applications, or any other fluid material.The application of sealing technology is spread almost everywhere, from domestic purposes to industrial applications.

The aim of this paper is to establish the optimized control of external variable displacement compressor (EVDC) for the automotive air conditioning (AC) system in various operating modes. The control logic was developed, calibrated and experimentally verified on test vehicle. The developed control strategy ensures the stability of AC system while achieving the desired climate control and yielding the maximum possible fuel economy. The influence of cooling load, compressor speed and icing of evaporator have been investigated theoretically and validated with test data. The proposed control strategy ensures the safety of compressor and stabilizes the AC system under high engine torque demand, cold start conditions, engine shutdown or under electrical failures reported by on board diagnostics services (OBD). The results reveal improved thermal comfort and improvement in fuel economy with the use of established baseline control logic presented in the paper.

Vehicle air conditioning and heating system is one of the most important part of an automobile system. Computational fluid Dynamics (CFD) is widely used to predict air flow rates and distribution in such Heating Ventilation and Air Conditioning (HVAC). Commercial CFD codes such as FLUENT and STAR-CCM+ are widely used in simulation for industrial research. But usage of these software comes with a heavy cost. Cost is one such parameter which industries try to bring down, without compromising on the deliverables in product development. OpenFOAM is one such license free, open source code that can be used to modify and compile its code based on the needs and the physics of the problem in hand. This study assessed the performance of airflow magnitude and distribution in an HVAC using OpenFOAM. The results between STAR-CCM+ and OpenFOAM were compared in terms of grid-independent solutions using various scalar and vector plots.

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.

For an efficient automotive AC system it is very essential to ensure uninterrupted and consistent airflow and temperature at the vent exit to help achieve the comfortable cabin space. This certainly requires temperature sensor to position at lowest possible temperature on heat exchanger and uniform flow distribution over it. However the uneven distribution of airflow on evaporator entry face leads to lowest temperature and sometimes goes undetected. This causes the condensate to get freezed and then frosting occurs at the core surface. Eventually a substantial portion of evaporator face gets choked and gradually airflow reduces and evaporator exit air temperature shoots up. Hence it is very important to prevent the frosting on evaporator core so to have uninterrupted airflow and adequate cooling in the passenger compartment. The present paper investigates the reasons for frosting occurring in one of the hatchback vehicle in bench test.

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.

Transport sector comes under largest energy consuming category, after mining and other industries, a significant fuel economy improvement are required to reduce green house emission. Till now the most promising technologies in this attempt are electric vehicle. Electric vehicles use large batteries to store energy, most common battery used in electric vehicles are lithium ion and lithium polymer preferred due to their high energy density compared to weight. The flow of current causes heating in the battery cells, performance of Lithium-Ion battery cells is greatly impacted by their temperature. For optimum performance it should operate in desired temperature range (15°C-35°C). Battery cooling system is the system which maintain optimum temperature of battery by cooling/heating to increases the thermal efficiency of vehicle. Most common Battery Thermal Management methods used today are, Air Cooled, Indirect liquid Cooled and Direct Cooled.

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.

Maintaining thermal comfort is one of the key areas in vehicle HVAC design wherein airflow distribution inside the cabin is one of the important elements in deciding comfort sensation. However, the energy consumption of air conditioning system needs to stay within the efficient boundaries to efficiently cool down the passenger cabin otherwise the vehicle energy consumption may get worsened to a great extent. One approach to optimize this process is by using numerical methods while developing climate systems. The present paper focuses on the numerical study of cabin aiming and cabin cool-down of a passenger car by using computational fluid dynamics (CFD). The main goal is to investigate the cabin aiming with a view to figure out the minimum average velocity over the passengers at all vent positions. Cabin aiming ensures substantial amount of airflow reaches to the passengers as well as every corners of the cabin across the wide climatic range.

In order to ensure a comfortable space inside the cabin, it is very essential to design an efficient heating ventilating and air-conditioning (HVAC) system which can deliver uniform temperature distribution at the exit. There are several factors which impact on uniformity of temperature distribution. Airflow distribution is one of the key parameter in deciding the effectiveness of temperature distribution. Kinematics links and linkage system typically termed as ‘mechanism’ is one of the critical sub-systems which greatly affects the airflow distribution. It is not the temperature uniformity but also the HVAC temperature linearity also depends on airflow distribution. Hence the design of mechanism is incomparably of paramount importance to achieve the desired level of airflow distribution at HVAC exit. The present paper describes the design methodology of automotive HVAC mechanism system.

Rapid advent of mobile air conditioning industry has witnessed a wide use of fixed displacement swash plate compressor due to its small size, compact structure and light weight. An accurate prediction of volumetric efficiency and power of compressor at early stages of design serves as a very useful information for designer. No work regarding the power and volumetric efficiency prediction for double headed fixed displacement swash plate compressor is reported in the existing literature. This paper presents a mathematical model for a double acting fixed displacement swash plate compressor with the objective of evaluating the shaft torque and volumetric efficiency of compressor. Shaft torque, in turn is a measure of compressor power. The geometrical description of swash plate yields a kinematic model to obtain the piston displacement as an explicit function of angle of rotation of shaft.

An Integral Receiver-Dryer Condenser (IRDC) is one amongst the many recent developments in the field of automotive air-conditioning system. With proper design, these condensers facilitate an increase in the A/C system performance with reduced packaging space and refrigerant charge. The performance of these condensers depends on different parameters like the charge quantity, size of the receiver, subcooling area, pass structure, position of the receiver with respect to the condenser passes and liquid-vapor separation in the receiver. If these parameters are not taken into consideration in the design of an IRDC, the condenser may not give the desired cooling performance, which in turn will affect air-conditioning system performance. We discuss these parameters in detail and their effect on the performance of an IRDC in an A/C system.