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Commercial electric vehicle air conditioning system keeps occupants comfortable, but at the expense of the energy used from the battery of vehicle. Passengers around the world are increasingly requesting buses with HVAC/AC capabilities. There is a need to optimise current air conditioning systems taking into account packaging, cost, and performance limits due to the rising demand for cooling and heating globally. Major elements contributing to heat ingress are traction motor, front firewall, windshield & side glasses and bus body parts. These elements contribute to the bus’s poor cooling and lack of passenger comfort. This topic refers to the reduction of the heat ingress through usage of different glass technology like IR Cut & solar green glass with different types of coating.

AC system provides the human comfort inside the cabin of a vehicle but at the expense of consumption of energy from the vehicle. On a global perspective for the bus segment, there is an increased demand for cooling in tropical countries. Optimization needs to be done in existing AC systems w.r.t packaging, cost & performance constraints. Major elements contributing to heat ingress are engine hood, front firewall, windshield & side glasses and bus body parts. Due to these reasons inadequate passenger comfort and poor cool down performance of the vehicle is observed. This paper refers to the reduction of heat ingress through different DOE (Design of Experiment) in the area of design & validation for duct & vent layout, insulation, glass & paint technology, evaporator blowers. The new duct design has been evaluated using a CFD tool by varying various parameters to generate desired output. The integrated use of the modifications was found significant improvement at vehicle level.

HVAC system design has an accountability towards acoustic comfort of passengers of a vehicle. Owing to larger cabin volume of a bus, multiple air blowers have to be installed to ensure comfort of passengers. Such multiple blowers produce significant flow induced noise inside the cabin. For commercial success, it becomes essential to predict intensity of such a flow induced noise at very early stages in product development. Conventionally sliding mesh based CFD approach is deployed to predict flow and turbulence noise around each blower. However due to complexity, this method becomes computationally intensive resulting in cost and time inefficiency. Hence it is desirable to innovate around an alternative rapid, reliable prediction method, which ensures quick turnaround of prediction.

Mobile Air Conditioning (MAC) system provides year round thermal comfort to the occupants inside vehicle cabin. In present scenario, 1D CAE simulation tools are widely used for MAC system design, component sizing, component selection and cool down performance prediction. The MAC component sizing and selection mainly depends on cooling load which varies with ambient conditions, occupancy, cabin size, geometry and material properties. Therefore, detailed modeling of vehicle cabin is essential during MAC system digital validation as it helps to predict performance across wide number of contributing factors. There are two different methods available in 1D Simulation for vehicle cabin modeling, viz. ‘simple cabin’ and ‘advance cabin’. With the simple cabin modeling approach, vehicle cabin is modelled as a group of lumped masses, which only enables prediction of average vent and average cabin temperatures. In advance cabin modeling approach, vehicle cabin is modelled more comprehensively.

Currently automotive sector is facing bi-fold challenge of light weighting and cost reduction. As end-customer is getting more focused on total cost of ownership, it is need of time that light weighting and cost reduction goes hand in hand. Presently lightweight materials such as magnesium, aluminum & composites are used but often this impact towards cost increase. In present study, a novel approach has been followed which not only focus on light weighting but also integrate design functions of two engine systems. This paper deals with the new system design to focus on low cost, light weight, NVH friendly and low development time. In design phase, function of two engine systems i.e. engine cover and Air filter were integrated followed by structural analysis. In final phase of this project, the experimental component was developed and validated for its intended function.

With Continuous increase in demand to reduce weight is forcing Automotive Designers towards finding ways to explore new materials for the Engine components. Currently, Aluminum, Thermoplastics and Composites are widely used in Engine application. This paper examines the potential of a Magnesium alloy Front Cover designed to replace the Cast iron Front Cover in a Light duty Diesel engine. In presented study, a Cast iron Engine front cover is re-designed for Magnesium alloy and components developed. Further Magnesium alloy component tested at vehicle level and it has been demonstrated that a magnesium alloy Front cover can achieve key functional requirements such as Structural durability, Sealing, NVH, while providing substantial Weight saving.

Virtual Product Development (VPD) with a vision to eliminate prototype testing is the recent trend in the automotive industry. Reducing the total vehicle development period with optimized output has been the major advantage of this new trend, fueled by increasing competition and shorter product life cycle. In this regard, Computer Aided Engineering (CAE) has taken a more significant role than ever in the vehicle development programs. Prediction of road noise in passenger cars is one of the important attributes to NVH (Noise Vibration Harness) Simulations. In the present work, CAE - NVH simulation of road noise is carried out on the finite element model of the vehicle, eliminating the costly and laborious test procedures & the process of awaiting information from various departments. One of the major challenges in these simulations are generating the load inputs for the structure-borne road noise in a cost and time saving method with accuracy.

Currently automotive industry is facing bi-fold challenge of reduction in greenhouse gases emissions as well as low operating cost. On one hand Emission regulations are getting more and more stringent on other hand there is major focus on customer value proposition. In engine emission the blow by gases are one of the source of greenhouse gases from engine. Blow-by gases not only consist of unburnt hydrocarbons but also carry large amount of oil. If oil is not separated from these gases, it will led to major oil consumption and hence increase total operating cost of Vehicle. Considering the above challenges, effort taken to develop a low-cost closed crankcase ventilation with oil mist separation system on diesel engine. For cost-effective solution, two different design and configuration of oil mist separation system developed.

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].

Durability of an exhaust system of an automobile is vital to its overall performance as well as customer satisfaction. Existing CAE approach involves simplified modelling & approximations and hence, offers a good scope to model critical details that have a definite bearing on the reliability of its prediction. In this work, an attempt has been made to capture all details such as effect of bolt pre-load on the rubber bushes/isolators, actual 3D model of the rubber bushes/isolators, material property based on measured load-deflection characteristics of the rubber bushes/isolators & contact interactions of mating surfaces that were apparently missing in the existing approach. All such modelling enhancements were incorporated in the model, which was then solved using non-linear solution technique.

OEMs are seeking to develop vehicle light weighting strategies that will allow them to meet weight and fuel economy targets hence increasingly shifting their focus towards incorporating lighter material solutions at mass produced scales. Composites are seen by automotive manufacturers as the solution to lightweight vehicles without affecting their performance. More and more parts are made of short fiber reinforced plastics (SFRP) as well as continuous fiber composites. However, replacing metals by composites requires a new design approach and a clear understanding of the composite behavior. This paradigm however requires a dedicated tool for composite design in order to take into account the specific composite behavior. Traditional design tools are not able to state accurately the composite material behavior and sometime leading to use high safety of factors and lack of confidence in the design.

Emission norms across the world are getting more and more stringent day by day, in pursuit of saving the mother Earth. Automotive industry is quick to respond to this huge challenge. One solution lies in making the vehicles lighter. That's why scope of the lightweight materials is more and more realized and explored during the last decade. One of the front runners in the lightweight material is Carbon Fiber Reinforced Polymer (CFRP). CFRP comes with own challenges in its understanding, designing and engineering. For effective use of the CFRP material, from a design and mass point of view, it has to be optimized in such a way that every section and layup is utilized to its maximum potential. Current paper demonstrates the multi-step optimization approach used in a design and development of car hood. Initial assessment of the hood showed that few attributes were falling short of the requirement targets, and could only be achieved with a mass penalty.

In today’s manual transmissions of car, gearshift system requires high performance with particular emphasis on low effort, minimal travel and positive feel. To meet these targets, a high capacity multi cone synchronizers along with higher co-efficient of friction material used for lower gears. The design of synchronizer with these specifications is influenced by torsional fluctuations from engine. Excessive torsional vibrations leads to wobbling of synchro rings within the peripheral clearances with surrounding parts. Wobbling leads to abrasion wear of frictional area of synchro ring causing grating or crashing noise of gears during shifting. This paper presents the optimization of the multiple cone synchronizer design exposed to excessive torsional vibrations and validation of the same on test bench during development stage instead vehicle level validation.

Physical testing of a vehicle wading through water is performed to gauge its capability to traverse through shallow to deep levels of water, wherein various vehicle performance parameters are observed, recorded and analysed. Jaguar Land Rover (JLR) has instigated and established a comprehensive CAE test procedure for assessing the same, which makes use of overset mesh (in a CFD environment) for a non-traditional approach to vehicle motion. The paper presents investigations made into the established wading physics, in order to optimise the splashing and water jet modelling. Large Scale Interface model was implemented instead of the previously standardised VOF-VOF fluid phase interaction model, and a comparison is made between the two. The implemented wheel rotation approach was scrutinised as well and appropriate inferences are drawn.

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.

The entire commercial vehicle industry is moving towards weight reduction to leverage on the latest materials available to benefit in payload & fuel efficiency. General practice of weight reduction using high strength steel with reduced thickness in reference to Roark’s formula does not consider the stiffness & dent performance. While this helps to meet the targeted weight reduction keeping the stress levels within the acceptable limit, but with a penalty on stiffness & dent performance. The parameters of stiffener like thickness, section & pitching are very important while considering the Stiffness, bucking & dent performance of a dumper body. The Finite Element Model of subject dumper body has been studied in general particularly on impact of dent performance and is correlated with road load data to provide unique solution to the product. The impact of payload during loading of dumper is the major load case.

Safety and Comfort are the core requirements of the automotive seating systems. Number of the occupants, determines type of the seating system requirement. The second row seat often needs to fold and slide, to allow the passenger to enter inside the car. Folding second row seat will also allow accommodating larger length cargo. The over folding of seat is controlled by hard stop mechanism. The hard stop mechanism generally consists of the seat arm stopper at back seat and hard stop located at base of the seat. These stoppers will limit the further motion of back seat. The folding speed of back seat is governed by various factors e.g. adjacent seat foam/structure friction, location, structural mass of seat etc. The scope of the paper is to evaluate various folding speeds of the back seat. Its effects are evaluated for the stresses and fatigue life of the hard stop components.

Success of the vehicle in the market depends on comfort provided while usage, which also include level of noise, vibration and harshness (NVH). In order to achieve good cabin comfort, the NVH levels have to be as low as possible. Powertrain is main source of NVH issues on vehicle and typically mounted on vehicle using rubber isolators. The dynamic characteristics of rubber isolators play vital role in reducing the vibrations transfer from powertrain to vehicle structure while operation and during dynamic conditions. Traditionally, isolators are manufactured using Natural Rubber (NR) to meet functional requirements which include vibration isolation and durability. At times either of above requirements has to be compromised or sacrificed due to the limitation in compounding process and other practical problems involved with manufacturing of rubber parts.