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Compressed Natural Gas (CNG) engine has proved itself to be worthy replacement for diesel in heavy commercial and passenger transport application all over the world. In India, infrastructure development of CNG distribution and stringent emission regulations have increased the interest shown by Original Equipment Manufacturers (OEM) to concentrate to development of CNG vehicles in every segment. Indian cities are fighting pollution due to high vehicle density and since contribution of light commercial vehicles in intra city application is significant, application of dedicated CNG vehicle has been made mandatory. This paper discusses the development of dedicated CNG engine using injection technology meeting the upcoming BS-IV norms. The primary modifications made are in the cylinder head, piston, intake and exhaust systems. The engine being developed for commercial application, the best in class fuel economy is of prime focus.

Beyond BS-IV, meeting emission legislation is an exigent target for diesel engine manufactures. But there always exist a compromise between engine performance and emissions. However the development of proper combination of Fuel Injection Equipment (FIE) system along with low cost after-treatment development for Indian vehicle applications to reduce the emissions plays major role to meet the engine target cost. Therefore in this study significance of using K and Ks nozzle is experimentally investigated for its effect on emission performance. In addition to maintain proper NOx/PM trade-off, an increased EGR flow rate along with higher cooling efficiency is improved. This increase in cooling efficiency is made without compromising other requirements in the design of the EGR cooler. The buildup of carbon deposits in EGR coolers causes significant degradation in heat transfer performance, often on the order of 15% - 20%.

Compressed Natural Gas (CNG) is now looked upon as a leading renewable fuel for vehicles in INDIA due to mounting foreign exchange expenditure to import crude petroleum. Impending stringent emissions regulations for diesel engines, specifically exhaust particulate emissions have caused engine manufactures to once again examine the potential of alternative fuels. Much interest has centred on CNG due to its potential for low particulate and hydrocarbon based emissions and adulteration hostile nature. Significant amount of research and development work is being undertaken in INDIA to investigate various aspects of CNG utilization in different types of engines. This paper discusses the methodology for conversion of a diesel engine to dedicated CNG engine and to make the engine to meet EURO-V norms. The primary modifications are made on the piston, cylinder head, intake manifold, throttle body adaptation and exhaust system.

The objective of the diesel engine development program is not only providing the maximum thermal efficiency but also to meet future stringent emission targets. The focus should be on controlling and reducing the unburned emissions, especially blow-by emission apart from controlling burnt emissions. In some extreme cases blow-by may contribute up to 50% of the total oil consumption of the engine. These blow-by emissions are the responsible phenomena for the engine operation, the economy and ecology expressed through the oil consumption and oil change interval rates. Engine breathing system is the most complex circuit within the engine, the air entrapment into space above oil in engine system is pushing more oil from sump. This should be avoided. In effect of controlling these factors the engine breathing system should be properly designed and maintained.

When an automobile negotiates a flooded region, water is splashed due to the rotational motion of the wheels. This water enters the air intake system of the turbocharged intercooled engine along with air and can pass through the turbocharger, intercooler and enter the engine. As water is an incompressible fluid, the piston cannot compress water inside the cylinder which leads to connecting rod bending and severe engine damage. This paper explains how the same has been resolved using CFD methodology and proposes the re-designed model of mud cover as a solution to this problem. The entire process has been streamlined and major time and cost reduction achieved by using simulation for optimization. The simulated results have been validated by extensive trials for correlation and outdoor tests for durability. Same analysis technique is used as a template to modify the air intake system.

The amount of air sucked by an I.C. engine is one of the main factors in defining the combustion efficiency, power output and volumetric efficiency. This paper discusses various geometries of the air filter and pipes to reduce the pressure losses in the air intake system of a Common Rail Direct Injection (CRDI) engine using Computational Fluid Dynamics (CFD) methodology and how integration of various available softwares can be applied to design the air intake system of CRDI engine. Reduction in the pressure losses allows more air to enter inside the engine for the same amount of compressor work. It results in better volumetric efficiency. The entire process has been streamlined and major time and cost reduction achieved by using simulation for optimization. The simulated results have been validated by extensive trials for correlation and outdoor tests for durability. Same analysis technique is used as a template to modify the air intake system.

This paper describes an effort to optimize the design procedure by integrating a suite of virtual tools using available software and at the same time fool proofing the process by imbedding a Design and Failure Mode Effect Analysis (DFMEA). The same has been applied in the field of armored vehicles for defense services where cooling requirements are unique and operational conditions at the very extreme especially in the Indian context.

Present day technology is continuously being upgraded in order to meet demand for cleaner vehicles by meeting stringent emission norms. The other driving force is vehicle performance in terms of drivability, fuel economy and comfort. Gasoline engine meets all the requirements except fuel economy, where in diesel engine has an advantage. The need of the hour is to achieve drivability, comfort and fuel economy of diesel engine. Apart from development of direct injection common rail and hybrid electric vehicle, this need has also caused development of gaseous fuels like LPG. The gaseous fuel could be CNG, LPG or Hydrogen depending upon the availability. This will also help in delay of depletion of fossil fuel reserves. Main features of this technology are its cost effective operation, modular nature and adaptation on old generation of vehicles.

This paper describes the functions and features of synchroniser system used in manual transmissions. It gives the details of the mathematical relationships involved in the synchroniser operation. A program is made in C to predict the gear shift effort required at the hand ball for a given manual transmission. The effect of various synchro parameters namely coefficient of friction, cone angle, blocker angle, synchronising time on gearshift quality and performance of manual transmission is studied. Benchmarking of a transmission, designed for usage with higher-powered engine, is carried out with proven transmissions in the same application.

Organic, inorganic and physical water quality data are reported for water transpired by several species of higher plants using an engineering and scientific testbed for high-fidelity, biological water reclamation and recycling. Biologically-reclaimed water met NASA Shuttle potable and Space Station/Manned Systems Integration hygiene standards with regard to parameters tested without post-treatment. Water reclaimed from 10% urine showed a 100-fold reduction in organics and inorganics, demonstrating the efficiency of biological water reclamation and the usefulness of this testbed for scientific and engineering studies.

Aerodynamic investigations on the models of two types of bus coaches in operation with a transport corporation show that their drag coefficients are considerably large. An attempt has been made to evolve experimentally a streamlined shape with smallest drag coefficient within the operating constraints in India. The streamlined configuration was obtained by rounding the frontal corners systematically and tapering the roof at the rear end. It was possible to obtain a drag coefficient of 0.42 compared to the values of 0.93 and 0.63 for the unstreamlined configurations.