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Crankshaft is one of the critical components of an engine (5C: cylinder head, connecting rod, crankshaft, camshaft and cylinder block). It is subjected to repetitive and dynamic loads due to cyclic operation of an engine and inertia forces. Due to uneven mass distribution, failure zones occur near fillets and holes in journal locations during operation of the engine. Hence, this topic was chosen because of increasing interest in higher payloads, lower weight, higher efficiency and shorter load cycles in crankshaft equipment. Calculation of Crankshaft strength consists initially in determining the nominal alternating bending and nominal alternating torsional stresses, which multiplied by the appropriate SCF (Stress Concentration Factor), result in an equivalent alternating stress. This equivalent alternating stress is then compared with the fatigue strength of the selected crankshaft material. This comparison will show whether or not the crankshaft concerned is dimensioned adequately.

To compete with the current market trends, there is always a need to develop cost effective frame designs to meet the needs of the customer. During the development of new vehicles, the major focus is on weight reduction, so as to improve the load carrying capacity and fuel efficiency. Due to the introduction of new high strength materials, the static strength conditions can be met by the use of thinner frames, but the dynamic behavior of the frame deteriorates. The dynamic behaviors like ride and handling, comfort are affected by the stiffness of the vehicle frame. The stiffness of the frame is majorly defined by its vertical stiffness, lateral stiffness and torsional stiffness. The vertical stiffness of the frame plays major role in isolating road vibrations to frame mounted aggregates. The lateral stiffness plays a very important role in the handling of the vehicle and cornering ability of the vehicle. Torsional stiffness effects the roll and lateral load transfer distribution.

To compete with the current market trends there is always a need to arrive at a cost effective and light weight designs, hence the need for upgrading the existing/proven integral connecting rod to fracture split connecting rod. This technique provides gains as weight reduction and consequently reducing noise and vibration due to the decrease of the oscillating mass from the system. Using the proposed fracture split connecting rod, it is estimated that cost savings of up to 10%, reduction in weight and better fatigue performance (25% - 30%) can be achieved. For this, we have used simulation tools to reduce number of physical tests and thereby achieving considerable reduction in design and development time and cost. High carbon alloy steel used for manufacturing fracture split connecting rod and it doesn’t require additional heat treatment after hot forging.

Crankshaft is one of the critical components of an engine (5C: cylinder head, connecting rod, crankshaft, camshaft and cylinder block). It is subjected to repetitive and dynamic loads due to cyclic operation of an engine, inertia forces due to uneven mass distribution with failure zones as fillets and holes in journal locations. Fatigue is most common cause in failure of the crankshaft. Its failure will cause serious damage to the engine so its reliability verification must be performed. The load is applied as per the firing order of the cylinder for 2 revolutions of crankshaft, to cover firing condition of each cylinder. Loads with respect to crank angle or time are applied at respective locations and results are taken on 360 steps for 2 complete revolutions of crank. The topic was chosen because of increasing interest in higher payloads, lower weight, higher efficiency and shorter load cycles in crankshaft equipment.

The cabin or cab is an enclosed space where the driver and co-driver are seated. Structural parameters such as modal and stiffness characteristics are of key importance for its durability study and driver’s comfort. The desired strength and stiffness value of the cabin have to be met at the development phase itself. In developing new cabin models numerical simulations are used for estimating vehicle performance to reduce the development cycle. But, the conventional method of modeling the cabin using 2-d elements and performing subsequent iteration steps to arrive at the desired stiffness and strength value will be cumbersome and time consuming. Thus, a methodology of FE modeling of the truck cabin using 1-D elements has been proposed in this paper which will reduce the analysis time of successive iterations. For this purpose an existing proven driver’s cabin is modeled using 1-D elements.

A Coupled CFD - FE Analysis, referred as Conjugate Heat Transfer (CHT) Analysis or Fluid Structure Interaction (FSI), is very important for the processes that involves simultaneous energy exchange between solid and fluid domains. If we consider IC engines, Exhaust Manifold is one of the critical areas where above mentioned phenomenon takes place. In this paper, temperature distribution in solid parts of exhaust manifold is obtained through Computational Fluid Dynamics (CFD) analysis which uses Finite Volume Method (FVM) for solving Navier-stokes equation and energy equation. Whereas thermal stresses are predicted through FE analysis which is based on Finite Element Methods (FEM). It is obvious to validate CFD process before evaluating thermal stress. Therefore initially CFD results are compared with experimental results and found more than 88% correlation. Thereafter in FE analysis, temperature field from CFD is mapped to nodes of FE model and thermo-mechanical stresses are evaluated.

Advanced Non-linear topology optimization methods have been addressed as the most promising techniques for light weight and performance design of Powertrain structures. The theoretical achievements are obtained both mechanically and mathematically. Nowadays, the great challenge lies in solving more complicated engineering design problems with multidisciplinary objectives or complex structural systems. The purpose of this paper is to provide a forum to present new developments in structural Non-linear topology optimization. The advantage of the proposed method is that structural optimization on irregular design domains can be carried out easily. Furthermore, this method integrates the stress analysis and the boundary evolution within the framework of finite element methods. In this paper, mainly focused on the Commercial Vehicles Powertrain component i.e. Transmission Housing.

Proper sealing of an engine is very important parameter in an engine design. Even small amount of gas leakage from the engine can affect the overall performance of the engine during operation. There are two important factors in enhancing the efficiency of the sealing of the gasket are right tightening torque of bolts & gasket design. In this study, both the distribution of the contact pressure on the gasket, and the stresses of the cylinder head at different loading conditions, such as cold assembly, hot assembly, cold start, and hot firing, is simulated by commercial tool, based on the finite element method (FEM). The results shows that the efficiency of the sealing of the cylinder head gasket depends on the tightening torque of the hold-down bolts, without taking into consideration any thermal load resulting from the temperature distribution in the cylinder head.

The need to develop products faster and to have designs which are first time right have put enormous pressure on the product development timelines, thus making computer aided optimization one of the most important tool in achieving these targets. In this paper, a design of experiments (DOE) study is used, to gain an insight as to, how changes to different parameters of front suspension and steering of a passenger bus affect its kinematic properties and thus to obtain an optimized design in terms of handling parameters such as bump steer, percent ackermann error and lock to lock rotation angle of steering wheel. The conventional hit and trial method is time consuming and monotonous and still is an approximate method, whereas in design of experiments (DOE), a model is repeatedly run through simulations in a single setup, for various combinations of parameter settings.