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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.

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.

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.

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.

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.

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.

Natural gas has been considered and implemented as alternative fuel to gasoline and diesel powered vehicles worldwide. Although natural gas belongs to petroleum fuel family, it has considerable recourses worldwide to ensure long energy security and comparatively lower carbon to hydrogen ratio that make it more environment friendly. This paper presents the effect of long duration endurance test on gas engine oil along with performance and emission characteristics of 5.8 L turbocharged heavy duty natural gas engine. The six cylinder engine was chosen due to its importance for urban bus transportation. The engine was subjected to long duration endurance test of 800 hrs with closed loop monitoring and controlled conditions as per 6 mode engine load cycle. During the complete endurance test of 800 hours, performance and emission characteristics of the engine were analyzed after completion of every 100 hours as per Full Throttle Performance Test and European Transient Cycle (ETC).

CABIN design is continuously undergoing a huge change for reasons of customer comfort on for meeting regulatory requirement. Consequently the strategic design process will not only consider need for high strength structures but a pragmatic research based approach utilizing the latest technology. Though cab structure is built by a sheet metal blank as per the required dimensions, some locations encounter great amounts of stress and must be designed to withstand the same in a durable way. A possible simpler practice would be to add reinforcements in the high stress area or use high strength material for the entire part. However in this approach weight and cost of the component will be increased. As the weight of the Cabin, vehicle increases this will impact fuel efficiency. Attempts have been taken like using composite materials.

Rapid growth in the Indian economy has led to new market trends for commercial vehicles. Customers now expect high levels of comfort from all tactile points in a truck cabin; the gear lever knob is frequently used and its reactions greatly influence how a driver perceives Gear Shift Quality (GSQ) and thereby vehicle quality. The subjectivity of human perception is difficult to measure objectively; therefore this paper represents an objective methodology to correlate customer feedback of gearshift reactions. For the attribute evaluation of a set of intermediate commercial vehicles; detailed subjective appraisals were conducted by expert level assessors for GSQ sub-attributes, and a consecutive objective measurement was performed to investigate and substantiate these vehicle assessments.

In heavy commercial vehicle segment in India, driver comfort and feel was largely ignored. Fierce competition in the recent years and buyer’s market trend is compelling the designers of heavy truck to focus more on the finer aspects of attribute refinements. Steering is one driver-Vehicle interface which the driver is engaged throughout. Comfort and feel in steering wheel is defined by parameters like steering effort, manoeuvrability, on-center feel & response, cornering feel & response, Torque dead band, return-ability etc. and is influenced by a long list of components and systems in the truck. This study focuses on the influences of jacking torque and steering system friction on the on-center driving performance. Experiments to measure the Jacking torque and steering system friction were conducted in the lab and subjective and objective assessments of on-center driving performance were later conducted at test track in two similar 12 Ton truck to correlate their effects.

In this paper, experimental evaluation was carried out on a 6.0 L heavy duty CNG engine which has been optimized for 18 percent hydrogen blended CNG (HCNG). Optimization test results shows that use of HCNG results in reduced CO, THC & CH4 emissions by 39, 25 & 25 percent respectively and increase in NOx by 32 percent vis-a-vis CNG. After optimization the engine was subjected to endurance test of 600 hours as per 15 mode engine simulated city driving cycle with HCNG. The performance & emission characteristics of the engine were analyzed after completion of every 100 hours as per European Transient Cycle (ETC). Test results indicate that there were no significant changes observed in engine power output over the complete endurance test of 600 hrs with HCNG. Specific fuel consumption (SFC) measurements were consistent at all the 15 modes of engine simulated city driving cycle.

Steering gear box function is one of the important requirements in heavy vehicles in order to reduce driver fatigue. Improper functioning of steering gear box not only increases the driver fatigue, also concerns the safety of the vehicle. In this present investigation, the engine oil mixing up with steering oil has been identified and steering gear box failure has been observed in the customer vehicle. The root cause of failure has been analyzed. Based on the investigations, in particular design of steering pump has been failed at customer end. The same design of steering pump were segregated and analyzed. Initial pressure mapping study has been conducted. The pressure mapping results revealed that the cavity pressure obstructs the flow of suction pressure. It indicates that obstacle at suction port due to the existence of internal leakage that causes back pressure in the internal cavity of steering pump which sucks engine oil.

The commercial vehicle industry is evolving faster with the rise in multifarious aspects deciding a company's progress. In the current scenario, vehicle performance and its reliability in the areas of payload, fuel economy, etc. play vital roles in determining its sustenance in the industry, in addition to reducing driver fatigue and improving comfort levels. Test quality and time is the key to assure and affirm, smooth and quick launch of the product into the market. This paper details on the design of Multi-Axis road data simulator which entails realistic loads onto the components for capturing meaningful information on behavior of the product and recreate the field failure modes. The design was conceptualized keeping in mind both cost (for initial installation and running cost) and time for testing without loss in the convergence factor.

The emerging trends in commercial vehicle technology have increased the necessity for critical attribute engineering refinements. Drivability is emerging as one of the most significant attributes in the automotive sector. The degree of smoothness in a vehicle's response to the driver's input is termed as drivability. This attribute has to be rigorously refined in order to achieve brand specific vehicle characteristics, which will ensure a thorough product differentiation. In order to calibrate for a positive drivability feel, a methodology for evaluation of drivability is a prerequisite. The scope of this paper is aimed at describing the methodology for subjective and objective evaluation of drivability attributes in commercial vehicles. Drivability is a highly subjectively perceived attribute, therefore a subjective assessment technique to assess drivability attributes and sub-attributes are essential.

Steering wheel being the most used tactile point in a vehicle, its feel and response is an important factor based on which the vehicle quality is judged. Engineering the right feel and response into the system requires knowledge of the objective parameters that relate to the driver perception. Extensive correlation work has been done in the past pertaining to passenger cars, but the driver requirements for commercial vehicles vary significantly. Often it becomes difficult to match the right parameters to the steering feel experienced by the drivers, since most of the standard ISO weave test units used to describe them are of zero or first order parameters. Analyzing the second order parameters gave a better method to reason driver related feel. Also, each subjective attribute was fragmented into sub-attributes to identify the reason for such a rating resulting in the identification of the major subjective parameters affecting driver ratings.

Engines of commercial vehicles deliver significant amount of power (more than 25% of propulsive power) for non-propulsive loads such as air-conditioner, alternator, air compressor, radiator fan, steering oil pump, lights etc. Use of these auxiliaries cause sub-optimal utilization of engine power resulting in increased fuel consumption and emissions. A fuel cell powered auxiliary power unit (FC-APU) is proposed to isolate the auxiliaries from the engine. Use of FC-APU shall help improve load carrying capacity, gradeability, fuel efficiency and emissions of the vehicle. This paper describes a mathematical system level model developed using MATLAB-SIMULINK to estimate auxiliary power consumption and simulate FC-APU system. A statistical analysis is performed on the power consumed by various auxiliaries during different duty cycles. The data is used to propose a FC- APU system. Fuel cell is the most expensive component in the system.

This paper describes a methodology for design and development of On-Board Diagnostic system (OBD) with an objective to improve current reliability process in order to ensure design & quality of the new system as per requirement of commercial vehicle technology. OBD is a system that detects failures which adversely affect emissions and illuminates a MIL (Malfunction Indicator Lamp) to inform the driver of a fault which may lead to increase in emissions. OBD provides standard and unrestricted access for diagnosis and repair. Below given Figure 1 shows the working principle of OBD system. The exhaust emission of a vehicle will be controlled primarily by Engine Control Unit (ECU) and Exhaust Gas After Treatment Control (EGAS CU). These two control units determine the combined operating strategies of the engine and after treatment device. Figure 1 Modern Control Architecture for OBD System in Commercial vehicle [1]

Generally it is observed that in city buses most of the time, passenger seat fails at the seat mounting area in buses which are used for more than 3 years. This fatigue failure doesn't get captured either in Anchorage Test or Limited Vibration Test. Passenger seats' durability should be equal to vehicle life which is 10L km or 12 Years of life span. Physical testing on the vibration test rig is time consuming and costly. Most of the time machine availability for testing will be an issue, to validate alternate seat proposals. So there is a need to establish a correlation between physical testing and CAE simulation so that alternate proposals can be easily and quickly verified using CAE alone. This paper deals with the verification and validation of passenger seat in buses for life cycle requirement, through various methodologies adopted from data collection, CAE verification and physical validation to simulate real-time environment.

Improved economic growth and infrastructure in India has led to new market trends for commercial vehicles. Customers now expect high levels of comfort from all tactile points in a truck cabin; among them the gearlever knob is frequently used and its reactions greatly influence how a driver perceives gearshift quality (GSQ) and thereby vehicle quality. The importance of the gear shift quality of manual transmissions has increased significantly over the past few years as the refinement of other vehicle systems has increased. In Gearbox, synchroniser is the major component whose performance will affect the peak engagement force to a large extent. Synchroniser mechanism allows gear change to be smooth, noiseless and without vibrations. Since the maximum synchronisation effort vary depending on the rate of the shift actuation, it is difficult to compare synchronisers in different transmissions by force alone.