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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.

The aim of this paper is to optimize flow distribution on various ports of the ventilation unit. To improve the passenger comfort, ventilation unit need to be redesigned to get the uniform distribution in all ducts. There were challenges for the design modification on the unit to meet the distribution. The major challenge was to meet the distribution on the duct outlet without doing any design changes on the ducts. Hence the adapter which is the intermediate part between the blower and duct assembly is modified and simulation is done on the various design changes by changing the design of the adaptor part. CFD analysis is carried out on the ventilation unit with iterative design changes and achieved the target airflow and distribution. The analysis has been carried out on STAR CCM+ software.

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.

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.

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.

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.

As the current market trend is emerging towards the compactness, better comfort and less emission, it is quite important that factors contributing to these aspects should be kept under control and maintained within the desired range. Heating ventilation and air conditioning (HVAC) noise is one such factor which significantly contributes in occupants’ acoustic comfort. It creates discomfort to the occupants while HVAC is in operation and eventually lead to fatigue. In a HVAC, there are several different types and sources of noise which cumulatively impacts the overall noise level. However, few of them are quite prominent and has maximum impacts on overall noise. It is very important to identify and measure these sources in order to take appropriate countermeasure to mask or eliminate them. In order to identify and measure the noise sources, various methods are used.

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.

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.

As the automotive industry is transitioning from conventional engine driven to electric battery driven, many of the vehicle aggregates are getting re-engineered and changing accordingly. Being air-conditioning manufacturer one of the aggregates that needs attention and focused effort is the Heating Ventilation and Air Conditioning system (HVAC). Acoustic comfort of electric vehicle gets impacted due to the HVAC noise in absence of engine and hence other noise sources becomes prominent which were earlier masked by the engine noise. It is important to understand the HVAC noise sources for implementing right countermeasures for masking the noise. There are three methods of noise source identification namely acoustical duct method, cocooning or lead covering method and near field method. Out of these method, acoustical duct method and near field methods are used for minor and major noise identification in this study.

As HVAC noise is becoming one of the key factors to end users in terms of enhanced comfort, it is important to understand and evaluate various noise sources of HVAC in details. With detailed understanding of various sources, it becomes easier to take appropriate countermeasures in design and subsequently eliminate. There are many methods available in industry to investigate the noise sources in details however those options are expensive and time consuming and require deep understanding of the acoustic. Acoustical duct methods are one such method which proves to be very much helpful in identifying the noise sources from different aggregates like kinematics mechanism, door/damper, servomotors, heat exchangers etc. These sources are typically defined minor noise sources. The present paper describes the detailed investigation of those minor noise sources through the use of acoustical duct method. An existing HVAC from passenger car was considered for this study.