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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.

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.

As the global warming due to carbon footprint is very alarming, vehicle emissions are getting stringent day by day. In such situation vehicle hybridization or fully electric vehicles are of obvious choices. However in any of the cases the battery cooling is a big concern area. As the heat produced by the battery need to be dissipated in the long run, it is of utmost need to develop and understand the battery cooling system. Present paper describes the experimental investigation of a battery cooling circuit. A complete bench comprising of both primary and secondary circuit is used for the testing. The primary circuit has a cooling unit with TXV, condenser and electric compressor run by high voltage. The secondary circuit consists of a chiller (integrated with TXV) unit responsible for battery cooling. The whole circuit typically resembles with one of dual air conditioning unit and uses one of known refrigerant used in vehicle AC system.

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.

Automotive Air Conditioning is the process of removing the heat and moisture from the interior of an occupied space to improve comfort of occupants. A condenser is a device or unit used to condense refrigerant from its gaseous to its liquid state, by cooling it. In so doing, the latent heat is given up by the substance and transferred to the surrounding environment. It is made of Aluminum Alloy Material and subjected to very high internal stresses due to refrigerant pressure, thermal / inertia and dynamic load. In order to evaluate the structural integrity of the condenser assembly under these loading conditions, operating frequency should be far away from the resonance frequency and component design should be robust to sustain external excitation load coming from the engine & road. The above design evaluation criteria is also applicable for piston of AC’s reciprocating compressor.

The total thermal management system development of electric vehicles requires identification of all inter-dependent thermal sub systems and optimized control strategy formulation. Each of the subsystems requires a favorable working environment for sustained reliability, performance and vehicle’s battery power savings. Controller Area Network (CAN) bus technology is established communication protocol for the unmatched merits it offers over wiring based systems. It coordinates all thermal devices, sensors and systems and will be more detrimental to the success of electric vehicles (EVs) in future. The functional requirements imposed by the vehicles’ batteries & charging systems, air conditioning systems, heating systems and electric powertrain raise new challenges particularly with regard to the power optimization and control.

The aim of this paper is to analyze Train Driver Cabin AC kit to improve performance of Rail AC unit. First CFD analysis has been carried out on the existing design to find the airflow on the condenser side. Based on the analysis result, design modification has been done to improve the air flow on the condenser side and thereby improving the cooling capacity of the unit. CAE analysis has been carried out to strengthen mount brackets of condenser fan. With the design changes, there is significant improvement found on the structural integrity. Modal frequency improved and dynamic stress been reduced. Based on final modified design, proto was developed, tested and found OK which further verified with CAE/CFD results.CAE analysis has been carried out using ABAQUS/Hypermesh software and CFD using STAR CCM+.

Compressor plays an important role in Automotive Air Conditioning (AC) System. It compresses the low pressure refrigerant and discharges the high pressure refrigerant vapour to condenser. Compressor performance mainly depends on two parameters, compressor oil and refrigerant gas charge quantity. Compressor oil is used to lubricate the movable parts in reciprocating compressors. Compressor oil is miscible in refrigerants in liquid state and amount of oil present in compressor increases the life of compressor. But, huge amount of oil may also reduce the thermal performance of system. Minimum gas quantity gives poor cooling performance and due to maximum quantity, increasing suction/discharge pressures, results in more compressor work and low cooling. This paper discusses the experimental analysis of refrigerant quantity, oil quantity in different ratios to improving the cooling performance of a passenger vehicle. Experimentation was conducted on 7 seater passenger car (hatchback).

Air Conditioning System is one of the key elements of vehicle to provide thermal comfort for passengers. The optimization of fuel economy of the vehicle while delivering best in class cabin comfort is one of the biggest challenges for any thermal engineer. However to reduce the risk of compromising vehicle energy consumption performance with respect to thermal comfort, optimization need to be done during the initial design stage. Internal Heat Exchanger (IHX) is one of the major components which can be used to balance both parameter. In recent studies, different types of IHX like co-axial IHX, spiral type IHX has been evaluated by designers for energy and performance optimization. Beside this micro design IHX and other IHX design have been studied and experimented. One of the problems highlighted during all these studies is optimization of IHX length for a given system is very difficult to avoid any adverse effect in performance.