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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.

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.

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.

In automotive design and development, there are different stages for product design. In this fast changing scenario product design, digital verification of design (CAE), physical validation of the product and launching of the same in short time is important in product development life cycle of any new generation vehicle. This paper proposes a new approach towards development of a green-field platform for commercial vehicles by improving reliability of CAE and thereby reducing the need for prototype testing and hence shortening development cycle and costs - we call it “Hybrid Mule”. This Hybrid Mule has complete design intent under-body and engine-house while upper-body is made of simple representative tubular space frame. FRP skin panels are attached to this space frame to create a safe environment for test-driver. FRP skin also provides early feel of styling in running condition and evaluates basic ergonomics and visibility.

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.

As revealed from J. D. Power surveys, today most vehicle owners consider perceived quality as a direct indicator of the vehicle build quality and durability. [5] The problem has become more prominent and noticeable in recent times, due to the desire for reduced cost, reduced weight targets, aesthetic demands, and crash requirements. The performance of the door assembly when subjected to an abuse load of sag and over opening is one such perceived quality indicator which gives the customer the first impression about the engineering and build quality of the vehicle. Door hinge inclination and hinge contact flushness tolerance are the major design parameters affecting this performance. Although these are an important design parameter, the precise quantification of the effect of these design parameters on door performance under abuse loading has remained somewhat elusive.

Designing a cabin tilting system for Light Commercial Vehicles using a single torsion bar becomes challenging considering the operator safety and stringent design weight targets. Performance of a good tilting system entirely depends on cabin mass and location of centre of gravity with respect to (w.r.t) to tilting pivot point. Cabin Mass and COG location are very difficult to estimate while designing a new cabin as it is dependent on the maturation of all other cabin aggregates and also the accessories added by the customer. Incorporation design parameter changes like increasing cab tilting angle and increasing torsion bar length, in the later stages of product development, becomes expensive. The objective of this paper is to come up with an optimum design of a single torsion bar tilting employing “Taguchi optimization” for deciding the optimum levels of control factors, which ensures desired performance (i.e tilting effort vs.

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.

Enriched ventilation and driver assistance systems which plays vital role in human thermal comfort and safety, are now necessities for the whole automotive sector. For faster cabin thermal comfort, air circulation around occupant’s body reveals higher cabin comfort index. In India natural and forced ventilation system is predominantly used in commercial vehicles as an economical solution for achieving interim cabin comfort over air conditioning system. Presently used forced ventilation system consist of electrically driven blower motor to remove stale air around human body which is adding alternator load and thus affects fuel economy. Remarkably, 22% of such auxiliary electrical load is taken by electrical components from engine generated power. In order to enhance cabin thermal comfort and conceivably reduce power usage, an effective air flow control system is need of hour.

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.