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The conventional internal combustion engines continue to dominate many fields like transportation, agriculture and power generation. Moreover, apprehension over oil price restriction has created an unprecedented demand for fuel economy. Diesel engine is mostly preferred for its higher thermal efficiency, high-torque and outstanding longevity. In recent days with flooded technologies, Uniqueness and the Differentiation of Product play vital role for a successful business in Auto Industry. The present invention is related to the Challenges of Design & Development of Conventional Diesel Engine to meet the stringent emission & performance requirements (BS-IV) of Internal Combustion engines, and more particularly to achieve the targets with conventional Fuel Injection Systems (Non-electronic Fuel Injectors, In-Line Fuel Injection Pump-Governed Electronically) with required sub-systems on IC engine.

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.

Bogie-type suspensions for trucks are comprised of two axles and a central spring pack on each side of the truck chassis. Bogie suspensions have a good load distribution between the axles and are used for severe applications in trucks, in off-road conditions thereby subjecting them to extreme stain and load. In today’s competitive market scenario, it of utmost importance to minimize down time in commercial vehicles as it directly corresponds to loss in business which leads to customer dissatisfaction. It is therefore essential to optimize and select the right material for each component in the bogie suspension system. This paper deals with the material selection and testing of one such component - Bogie Wear Pad. The bogie wear pad undergoes sliding friction throughout its lifetime during loading and unloading of bogie suspension. Three different materials are selected and their wear is measured under the same conditions of loading.

E85 (85% Ethanol + 15% Gasoline), as an alternative fuel has been widely used in spark ignited engines used in light duty vehicles. However, they are rarely used in spark ignited heavy duty engines. In this study, we used E85 in a 5.8 litre, multi cylinder, turbocharged, multi point - port injected, spark ignited heavy duty engine, to analyze the performance capability. As E85 has higher octane rating, the compression ratio was increased to 11.5:1. Experimental investigation of In-cylinder pressure was done and the engine’s ignition timing and injection duration was calibrated to operate the engine below peak firing pressure limits, without knocking. The experimental results showed that exhaust gas recirculation resulted in lower peak firing pressure and rate of heat release. The results of the engine test showed that E85 can be used in heavy duty spark ignited engines. The scope for future work is on addressing the higher BSFC and cold start from subzero temperature levels.

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.

In today’s commercial vehicle scenario, designing and developing a component which will never fail throughout its lifespan is next to impossible. For a long time especially in the field of automotive, any crack initiation shall deem the component as failed and the design requires further modification. This paper deals with studying the failure of one such component and understanding the effect the crack has on the overall life of the component i.e. understanding the remnant life of the component. The component under study was gear shift lever bracket and is mounted on the engine exhaust manifold. It experiences two types of loads: inertial load due to the engine vibration and gear shift load. Frequent failures were observed in the field and in order to simulate it at lab, an accelerated test approach was adopted. The engine operating speed was used to identify the possible excitation frequency which the component might experience.

The objective of this paper is to provide a reliable and robust mechanics based analytical approach for the accurate prediction of residual stresses in cold formed steel members. The forming residual stresses and associated equivalent plastic strains in cold formed corner sections are predicted with the assumption of elastic-perfectly plastic material model. The predicted analytical solution results are then compared with the existing analytical solution results. This work demonstrates that the exact estimation of forming residual stresses and equivalent plastic strains are possible with the inclusion of shift in neutral axis resulting from unequal thresholds of plasticity levels at the top and bottom surfaces of small radius corner sections. The predicted forming residual stresses and the associated equivalent plastic strains together define the initial conditions of corner sections for further non-linear structural behavior analysis of cold formed structures.

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.

New legislation’s, competition from global players and change in customer perception related to comfort parameters are key factors demanding manufactures to design and manufacture vehicles with very low saloon noise levels. The main causes for higher noise levels at passenger saloon compartment can be attributed to source noises (Powertrain, Driveline, Intake and Exhaust etc.), acoustic isolation and structural sensitivity of the body. Out of all above parameters, powertrain noise and acoustic isolation are two critical parameters effecting interior noise performance. This paper is an attempt to explain acoustic source contribution analysis through transfer function measurement in a passenger vehicle. Acoustic transfer function between engine bay and passenger ear level was measured using reciprocity technique (reciprocal method) with reference source placed at various locations inside the vehicle.

Bio-fuels potentially represent a more environmentally friendly alternative to fossil fuels as they produce fewer greenhouse gas emissions when burned. Ethanol is one such bio-fuel alternative to the conventional fossil fuels. Towards the initiative of sustainable transportation using alternative fuels, it is attempted to develop an ethanol powered engine for commercial vehicles and this paper attempts to explain the 1D thermodynamic simulation carried out for predicting the engine performance and combustion characteristics, as a part of the engine development program. Engine simulation is becoming an increasingly important engineering tool for reducing the development cost and time and also helps in carrying out various DOE iterations which are rather difficult to be conducted experimentally in any internal combustion engine development program. AVL Boost software is used for modeling and simulation.

Exterior noise reduction of a vehicle has become important nowadays in order to meet the stringent pass by noise regulations. First step in this process is the identification of dominant noise sources. There are several noise sources which can contribute to the pass by noise like gearbox, turbocharger, oil sump, exhaust muffler, air intake etc. The dominant noise sources can be identified with the near field noise, component vibration measurements combined with experimental modal analysis. This paper discusses about the noise source identification and exterior noise reduction of a shortest wheel base intermediate commercial vehicle, which is having a 4-cylinder inline diesel engine.

Engine mounts and mounting brackets play a critical role in determining NVH performance of a vehicle. A lot of work has been done in the area of virtual simulation using FE models to study engine mounting system performance and its impact on vehicle level performance. An overall approach towards engine mounting system validation at vehicle level is also very critical to validate simulation results in a prototype based on which further refinement work will be carried. In this paper a detailed procedure for engine mount and mounting bracket physical validation at vehicle level is presented. Various tests to be performed at vehicle level to quantify engine mount and mounting bracket performance parameters is discussed in detail along with measurement procedures and techniques. Test results are interpreted and its impact on overall performance is also explained. These test results will help design engineers to further improve engineering parameters of mounts and mounting brackets.

Engine noise reduction is one of the highest priorities in vehicle development from the viewpoint of meeting stringent noise regulations. Engine noise reduction involves identification of noise sources and suppression of noise by changing the response of sources to input excitations. Noise can originate from several mechanical sources in engine. The present work focuses on systematic study of the behavior or response of engine structure and its ancillaries to engine excitation and thereby assess their contribution to overall engine noise. The approach includes engine noise and vibration measurement and component ranking using engine noise and vibration measurement in a non-anechoic environment, structural analysis of engine including experimental modal testing of engine and its components, etc. Correlation of the above obtained results is performed to identify the noise sources. Later, ranking of critical components was performed based on results of cladding exercise.

Powertrain is the major source of noise and vibration in commercial vehicles and has significant contribution on both interior and exterior noise levels. It is vital to reduce the radiated noise from powertrain to meet customer expectations of vehicle comfort and to abide by the legislative noise requirements. Sound intensity mapping technique can identify the critical components of noise radiation from the powertrain. Sound intensity mapping has revealed that oil sump as one of the major contributors for radiated noise from powertrain. Accounting the effect of dynamic coupling of oil on the sump is crucial in predicting its noise radiation performance. Through numerical methods, some amount of work done in predicting the dynamic characteristics of structures filled with fluid. This paper discusses on the capability of numerical approach in predicting the oil sump modal characteristics with fluid-structure interaction and consequent verification with experimental modal test results.

Cross flow heat exchangers are very common in automotive vehicle thermal management systems. The most important and standard fitment of any vehicle is the radiator, a cross flow heat exchanger for engine cooling systems. As a vehicle manufacturer, selection of a cooling system based on the requirements is very critical especially when the radiators are sourced from multiple sources and of different configurations. So, these different types of radiator have to be compared on the same level for effective selection of heat exchangers. This demands the common methodology to be created to understand the heat exchanger performance with different geometrical input from different sources. In this study, an empirical cum analytical based methodology has been developed for generating the performance characteristics of the louvered fin heat exchanger using the thermal resistance and Number of Transfer Units (NTU) method.

In this paper, valve spring parameters are optimized based on an iterative logic with constraint on space availability, stress limit, stiffness and natural frequency of the system. The optimized valve spring configuration is used in the push rod type valve train and the valve train dynamics for different engine speed is studied using commercially available multi-body dynamic ADMAS software. The valve train components such as cam, tappet, push rod, rocker arm, valve retainers and valve are modelled as rigid bodies and the valve springs (inner and outer valve springs) are modelled as flexible bodies. Each coil of the springs is modelled as separate flexible body and contact between these coils are established. A comparative valve train dynamics analysis is also carried out with the existing and optimized valve spring combinations.

The two major areas of engine development, the automobile industry is concentrating and putting its major product development efforts on are emission control and improved fuel efficiency. These developments either directly or indirectly impact the cooling system requirements significantly. A small change in cooling system requires the vehicle to undergo cooling tests before commercial release to make sure it performs as per requirements. Normally, on an average, 4-5 trials are conducted before clearing the vehicle for production. This involves a lot of time, efforts and resources. The objective of this study is to develop a methodology to predict the cooling system performance analytically and validate the results with experimental data. This study will help in reducing the number of trials thereby saving cost, time and efforts involved. Basic components of cooling system include radiator, charge air cooler and fan.

The mechanical and wear behaviour of an alloyed gray cast iron with ausferrite microstructure directly obtained on solidification has been compared with austempered alloyed gray iron. As-cast ausferritic gray iron shows finer ausferrite and graphite flake morphology compared to austempered alloy. The volume of retained austenite is about 30% higher in as-cast ausferritic iron due to higher amount of alloying additions. The mechanical and wear properties of as-cast ausferritic iron are almost similar to austempered alloy.

In the emerging commercial vehicle sector, it is very essential to give a product to customer, which is very reliable and less prone to the failures to make the product successful in the market. In order to make it possible, the product is to be validated to replicate the exact field conditions, where it is going to be operated. Lab testing plays a vital role in reproducing the field conditions in order to reduce the lead time in overall product life cycle development process. This paper deals with the design and fabrication of the steering column slip endurance test rig. This rig is capable of generating wear on the steering column splines coating which predominantly leads to failure of steering column. The data acquired from Proving Ground (PG) was analyzed and block cycles were generated with help of data analyzing tools.

All automotive components undergo stringent testing protocol during the design validation phase. Nevertheless, there are certain components in the field which are seldom captured during design validation. One of these components is the battery isolator switch. This project aims at optimizing a validation methodology for this component based on field usage and conditions. The isolator switch is the main control switch which connects and disconnects the electrical loads from the battery. This switch is used in the electrical circuit of the vehicle to prevent unwanted draining of battery when it is not needed and when the vehicle is in switched off. An electrical version of this switch uses electromagnetic coils to short the contacts. The failure mode being investigated is a high current load causing the input and output terminal to be welded.