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The hybrid structure of Engine Mounts made of rubber casing with cast iron reinforcing. Use of two materials made it unique both in application and testing. The rubber provides damping for engine vibrations and the cast iron provides necessary strengthening to hold the heavy engine in place. In this research paper the FEA (Finite Element Method) methodology is being discussed to evaluate and optimize the design analysis to enhance overall engine mount capacity. The existing and modified designs are validated and considerable improvement is being observed in modified design in physical testing. Accurate modeling of engine mounts assembly is presented in this paper. FEA analysis results have good correlation with physical validation for both designs. Impact of design parameters of rubber mounts has been presented.

Euro 6 emission norms are getting implemented in India from April 2020 and it is being viewed as one of the greatest challenges ever faced by the Indian automotive industry. In order to achieve such stringent emission norms along with top performance for vehicle, a good strategy should be incorporated to control system out NOx emissions and soot regeneration. Extruded Vanadium catalyst is deployed for this passive regeneration system with DOC (Diesel Oxidation Catalyst), DPF (Diesel Particulate Filter) and SCR (Selective Catalyst Reduction), where the amount of catalyst loading in DOC plays an apex role in deciding conversion efficiency of SCR and passive regeneration capabilities. This study mainly focuses on the impact of catalyst loading of DOC over SCR efficiency. NO2 to NOx ratio should be close to 0.5 for optimum conversion efficiency of SCR. Catalyst loading in DOC decides the amount of NO2 coming upstream to SCR.

With implementation of stringent BSVI emission norms and regulations like OBD-II on vehicle, it is essential to define the life of exhaust after treatment along with the vehicle. Diesel after treatment generally consists of DOC, DPF and SCR. Lubricating oil contains phosphorus and zinc which adversely affect the DOC. Unburned hydrocarbons (UNHBC) and SOF in tail pipe get accumulated in the DPF. This requires regeneration process where in, high temperatures in exhaust after treatment (EATS) burn the adsorbed Sulphur or phosphorus, thereby improving the conversion efficiencies. Repeated regenerations lead to ash accumulation in DPF and this reduces its capability for soot accumulation. Sulphur in the exhaust impacts SCR through NOx conversion. The present study analyzes the effect of (1) Chemical aging (2) Thermal aging on 3.77 liter diesel engine after treatment. A test cycle was prepared to run the durability for EATS.

Diesel engines have always been popular for their low end torque and lugging abilities. With their higher thermal efficiencies through technical advancements, diesel engines are preferred powertrains in mass transportation of goods as well as people [14] [15]. A diesel engine always banks on excess air, which is subjected to higher compression ratios so as to achieve temperatures, enough to facilitate auto-ignition of diesel. With the advent of turbocharging and intercooling, the air availability is further enhanced, ensuring better combustion efficiency, lesser HC, CO and particulate matter (PM) emissions together with improved fuel efficiencies [2] [15]. Higher air availability also has its own shortcomings in the form of higher NOx (Nitrogen oxides) emissions. With stringent emission norms in place, reduction of NOx as well as PM, without sacrificing performance and fuel economy, is of utmost importance.

Highway transportation using truck is an important transport mode of goods and product to their destination. Commercial vehicle is expensive mode of transportation so it will be protected from failure. For Heavy duty truck they are fully loaded at one side of transportation and other side empty transportation. In such case lift axle grounded when truck is loaded and when truck is empty it is in lift condition. Lift axle is play important role while loading so it is important that it should not fail. Many times lift axle fails at weld location due several load come on the axle. In this paper study of weld failure to vertical, braking and lateral load come on lift axle when truck is in loading condition. Weld failure check in CAE analysis with various load cases and compare with actual physical vehicle failure. Weld failure correlation well correlate when actual loading are consider in analysis. For analysis loading data is measure from RLDA data that will be used for analysis.

Virtual validation of automobile components poses a huge challenge and needs continuous process improvements. One of such challenge in FE modelling of welds and understanding its behavior with respect to physical behavior. With the ongoing development of BSVI line of products in commercial vehicle industry, the virtual validation needs to be accurate and close to the physical behavior of the components. The learning and challenges faced during the previous development is implemented in the current study for weld simulation and correlation activity. The brackets welded to the power train components is taken as a challenge in the present work. Initially weld model was depicted in the CAD and was analyzed in CAE by providing proper FE connection. This practice had lot of flaws, approximations due to perpendicularity and flatness concerns in the models leading to consuming a lot of time in model preparation.

In recent times there has been rising demand for noise level reduction in commercial vehicles. Vehicle engine exhaust system is one of the key sources of noise at driver ear, especially in smaller wheel base vehicles, as well as critical for meeting pass by noise regulations. Several techniques are used to reduce the noise level of an exhaust system such as resonators, dissipative mufflers for low & high frequencies respectively. In this paper sound transmission loss (STL) measurement for a LMD bus exhaust system was carried out at rig level. It has been found from the measured data that noise attenuation of current exhaust system is poor in low frequency zone & therefore lower STL frequencies were identified. To attenuate the noises at identified frequencies Helmholtz resonator was introduced, which is particularly effective for low frequency noise attenuation.

Diesel engines are facing stringent norms and future survival with its lower availability is one of the biggest concerns for OEMs of heavy duty commercial vehicles. This is leading to uplifting of new, latent and innovative techniques to achieve these norms with best possible BSFC to reduce overall diesel consumption. The prime objective of this study is to identify and explore the latent strength of pre and post injection on engine performance, emissions and oil dilution due to soot. The post injection strategy has the potential to reduce soot with almost same NOx and fuel consumption depending on the delay of post injection and its quantity. It aids to increase the engine out temperatures for assistance of after-treatment devices, thus meeting higher temperature requirements for NOx and PM conversion for stringent norms of BSVI.

A propeller shaft is a mechanical component of drive train that connects transmission to drive wheels/axle with the goal to transfer rotation and torque. It is used when the direct connection between transmission and drive axle is not possible due to large distance between their respective assigned design spaces. In commercial vehicles especially in heavy duty (GVW/GCW>15 tons) a single piece propeller shaft is seldom used due to its inherent disadvantages and therefore, most if not all, of the setups consists of multiple pieces of propeller shaft which are directly mounted on to frame cross members with the help of mounting brackets. As such the mounting bracket assembly undergoes various dynamic and static loading conditions and should be able to withstand these loads. This paper will focus on the FEA analysis of propeller shaft mounting assembly system. Furthermore, these results will be correlated with physical tests results collected from test rig and physical vehicle testing.

Air Pollution is a major concern in our country due to which Indian Government has taken a decision to move from BS-IV to BS-VI which is nearly 90% reduction in NOx and 50% in particulate matter along with addition of particulate number regulation for BS-VI in comparison to BS-IV norms in very short span of time. Vehicle manufacturers are also having the challenge to produce low cost and fuel efficient product with BS-VI solution in order to meet tightening emission regulations and increasing needs of lower fuel consumption. Detailed study is done with different approaches to meet BS-VI emission which is elaborately explained in different aspect of engine design and after treatment parameter with its pros and cons. After Treatment selection plays an important role in engine development to meet stringent emission legislations and customer demands. Strategies for BS-VI were described with the advantage and drawbacks for after treatment selection.

Engine down speeding is rapidly picking up momentum in many segment of world market. Numerous engine down speeding packages from OEM have been tailored to take advantage of the increased efficiencies associated with engine down speeding. Running engine at lower rpm has numerous advantages. The most obvious of these is reduced fuel consumption, since the engine can spend more time running within its optimum efficiency range. By down speeding, the engine is made to run at low speeds and with high torques. For the same power, the engine is operated at higher specific load- Brake Mean Effective pressure (BMEP) which results in higher efficiency and reduced fuel consumption-Brake Specific Fuel Consumption (BSFC). The reasons for increased fuel efficiency are reduced engine friction due to low piston speeds, reduced relative heat transfer and increased thermodynamic efficiency.

In an automobile, main function of the steering system is to allow the driver to guide the vehicle on a desired course. Steering system consists of various components & linkages. Using these linkages, the torque from steering wheel is transferred to tyre which results in turning of the vehicle. Over the life of vehicle, these steering components are subjected to various loading conditions. As steering components are safety critical parts in the vehicle, therefore they should not fail while running because it will cause vehicle breakdown. In commercial vehicle segment, vehicle breakdown means delay in freight delivery which results in huge loss to costumer. Therefore, while designing steering components one should consider all the possible loadings condition those are possible. But, it can’t be done through theoretical calculation. Therefore, physical tests have to be carried out to validate design of steering system, which is very costly & time-consuming process.

At the time of invention of road coaches, the vehicle consisted only of an axle with wheels and a body attached. Smooth roads were built for a better ride comfort however they were not consistent. The road coaches were too bumpy and uncomfortable for the passenger along with the driver who was not able to control the vehicle. That's why the engineers had to shift their attention to the suspension system for a better ride comfort and handling. The technology has advanced with time so as the suspension system. Rubber ended type leaf spring is one of the suspension system types available in the industry. The main function of a suspension in order of importance is as below: 1 Acts as a cushioning device ensuring the comfort of the driver and passengers; 2 Maximizes the contact between the tires and the road surface to provide steering stability with good handling; 3 Protects the vehicle itself and any cargo or luggage from damage and wear.

To compete with the current market trends there is always a need to arrive at a cost effective and light weight designs. For commercial vehicles, an attempt is made to decrease weight of the current design without compromising its strength & stiffness, considering/bearing all the worst road/engine load cases and severe environmental conditions. The topic was chosen because of interest in higher payloads, lower weight, and higher efficiency. Automotive cylinder head must be lighter in weight, to meet increasingly demanding customer requirements. The design approach for cylinder head has made it difficult to achieve this target. A designer might make some judgment as to where ribs are required to provide stiffness, but this is based on engineering experience and Finite Element Analysis (FEA) of the stand-alone head.