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The new emission requirement norms in India calls for a robust Exhaust and After Treatment System (EATS) in automobiles. Its main purpose is to reduce the emission of harmful pollutants into the environment. EATS have a series of components that cleans the diesel exhaust emitted by the engine prior to releasing it through the tailpipe to the outside air. All the EATS components must undergo stringent testing protocol prior to its implementation in vehicle. During the exhaust treatment process, a very high temperature of about 550°C is produced in the EATS system. Hence, the effect of this higher temperature needs to be considered for validation. Moreover, the components will undergo multi-axial vibration in real road conditions which also need to be simulated during validation. In addition, engine vibrations are directly transmitted through a flex bellow to EATS system. These vibrations need to be captured and simulated in component level testing.

In the past decades, many impressive progress has been made in the rig development for the gear validation. But, the challenges are to test the entire gear box for the improvement in the single gear alone to ascertain material quality or process improvement, that too with the higher torque range gear boxes, which requires huge investment and power consumption due to high capacity test rig / dynamometer. This paper deals with an experimental validation of the dynamic model for a gear pair test system, representative of a closed loop power recirculating type test rig. Being a closed loop, this system has its own uniqueness, that, it uses the low capacity prime mover, which considers the initial starting loop torque only, to cater the high power requirement in an efficient manner. The key intend of the development of this rig is to reduce the testing from system level to sub component level with low cost operation and more competence for the gears of high torque application.

In today’s competitive world to stay in the commercial vehicle business, technological advancement is vital. Understanding the various operation modes of a vehicle considering the vibration becomes essential for developing a vehicle free from failures. ODS analysis is a method which is used to visualise the vibration pattern of a vehicle when influenced by known external operating forces. ODS provide very useful information for understanding and evaluating the behavior of the vehicle. This paper discusses about the experiments carried out in vehicle. It details the process of data collection at varying frequency input, understanding the modes at various frequencies, identifying the resonant frequency of various components, understanding the comparison between road inputs and resonance frequencies and the transfer of vibration (Transmissibility) from one component to another.

The suspension system in a vehicle isolates the frame and body from road shocks and vibrations which would otherwise be transferred to the passengers and goods. Heavier goods vehicles use tandem axles at the rear for load carrying. Both the axles should be inter-connected to eliminate overloading of any one axle when this goes over a bump or a ditch. One of the inter-connecting mechanism used is leaf spring with tie rod, bell crank & linkages, when the first rear axle moves over a bump, the linkages equalize the loading on the second rear axle. This paper details about the failure analysis methodology to simulate the tie rod field failure using a six poster road simulator and to identify the root cause of the failure and further corrective actions.

The modern day automobile customers’ expectations are sky-high. The automotive manufacturers need to provide sophisticated, cost-effective comfort to stay in this competitive world. Air conditioning is one of the major features which provides a better comfort but also adds up to the increase in operating fuel cost of vehicle. According to the sources the efficiency of internal combustion engine is 30% and 70% of energy is wasted to atmosphere. The current Air conditioners in automobiles use Vapour compression system (VCS) which utilizes a portion of shaft power of the engine at its input; this in turn reduces the brake power output and increases the specific fuel consumption (SFC) of the engine. With the current depletion rate of fossil fuels, it is necessary to conserve the available resources and use it effectively which also contributes to maintain a good balance in greenhouse effect thus protecting the environment.

A full-bodied validation of automotive system emphasis on a comprehensive coverage of failure modes of component on one hand and evaluation with full system for the intended function of single component on the other has for long been cumbersome to most commercial vehicle manufacturers. This paper focuses on optimizing the test method in rig testing to relieve the complexity in the structural validation as whole system level. The methodology proposed by authors focuses on accelerating the vibration testing of component by compressing the validation timelines by using CSCPV (Combined Systematic Calculated and Pre Validation) method. This method selects the components of the system for validation by VFTM (Vital Few and Trivial Many) approach from existing testing database failure data and selects the worst predominant failure cases. This CSCPV method uses systematically calculated representing mass from analysis to validate the intended component alone instead of entire system.

In today competitive world, gaining customer delight is the most vital part of an automotive business. Customers’ expectations are high which need to be satisfied limitless, to stay in the business. The major expectation of a commercial vehicle customer is a vehicle without failures which involves lower spares cost and downtime. The significance of a suspension system in the new age automobiles is getting advanced. There have been many improvements in the suspension system especially in leaf springs to provide a better ride comfort, and one such modern era implementation is the Parabolic Spring which comprises of fewer leaves with varying thickness from the center to the ends without inter-leaf friction. Study reveals that parabolic spring exhibits better ride comfort, but less life compared to a conventional leaf spring which leads to the increase in downtime of the vehicle.