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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.

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.

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.