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In commercial vehicles, exhaust system is normally mounted on frame side members (FSM) using hanger brackets. These exhaust system hanger brackets are tested either as part of full vehicle durability testing or as a subsystem in a rig testing. During initial phases of product development cycle, the hanger brackets are validated for their durability in rig level testing using time domain signals acquired from mule vehicle. These signals are then used in uni-axial, bi-axial or tri-axial rig facilities based on their severity and the availability of test rigs. This paper depicts the simulation method employed to replicate the bi-directional rig testing through modal transient analysis. Finite Element Method (FEM) is applied for numerical analysis of exhaust system assembly using MSC/Nastran software with the inclusion of rubber isolator modeling, meshing guidelines etc. Finite Element Analysis (FEA) results are in good agreement with rig level test results.

Cold formed carbon steel C sections are often employed as load carrying structural members in heavy commercial trucks. The cold forming operations employed during the making of these members generate certain amount of residual stresses throughout the sections. As the residual stresses play a significant role in determining the structural behavior of truck frame rail members, a careful assessment of residual stresses resulting from cold forming operation is needed. In the present investigation, residual stresses in frame rail corner sections were numerically predicted with the help of non-linear Finite Element (FE) analysis in ABAQUS and compared with the experimentally measured residual stress values using X-ray diffraction technique. It has been observed that the numerically predicted residual stresses are in agreement with the experimentally measured residual stresses in forming direction.

Linear static analysis of heavy commercial truck chassis assembly has become an industry practice during the concept stage evaluation. Non-linear analysis of chassis is rarely performed due to computational time and resource constraints. However, linear assumptions might not be appropriate for certain regions in the chassis assembly. In this paper, sub-modeling technique is applied for solving specific regions in the full chassis assembly to capture the actual boundary information for local non-linear analysis without intervention of user.

In the recent years, due to rising fuel costs, transportation technologies that provide better fuel economy than conventional vehicle are gaining in popularity with masses. Also, tighter emission norms by various governments have prompted OEMs to look at alternate solutions such as hybrid vehicles. Hybrid vehicles employ an internal combustion engine as well as an alternate energy source to power road vehicles. Various types of hybrid vehicles are available such as mild hybrid, full hybrid, series, parallel and series-parallel hybrids. The level of hybridization (mild or full) and the different powertrain combination (series or parallel) result that on the same route, the engine in a hybrid vehicle operates very different to that of conventional vehicle. The fuel consumed and emissions are also significantly lower in hybrid vehicle. To certify hybrid vehicles, regulators in many countries have modified existing procedures applicable to conventional vehicles.

A roof fairing is a commonly used add-on for trucks or tractor-trailers, where a significant difference in height exists between the cabin and the container. A roof fairing reduces the aerodynamic drag on the vehicle by directing the onward wind flow smoothly onto the container and thus reducing flow separation in front of the container. Since standard containers are available in two different heights and there are cases when vehicles ply without load i.e. without a container, it is necessary to adjust the height of the fairing accordingly to maintain an optimum aerodynamic configuration. While adjustable fairings have been in use in the commercial vehicle industry, these fairings are usually shaped as flat plates, often with open sides for ease of folding. A highly curved and bulbous fairing helps in reducing drag better, especially in presence of side winds, although it makes adjustability difficult.