F2008-09-018
Methods to Improve the Performance of the New Generation of CNG Vehicles
Natural gas is an environmentally clean, plentiful, low cost, and domestically produced fuel for motor vehicles. It is increasingly seen as an effective alternative to gasoline and diesel in many internal combustion applications. The inherent environmental benefit of natural gas over gasoline and diesel fuel is a reason for this popularity. Many investigations have been carried out on the performance and exhaust emissions of natural gas fuelled engines. However, there are some challenges in using CNG (compressed natural gas) for spark ignition engines, which result in low power and increase in some of emission vaues, such as NOx and THC, in spite of considerable decrease in CO and CO2 values with respect to gasoline engines. Therefore, there is a need to do more research on this topic. This paper present some new technological improvements in injection system, ignition equipment, and engine management programming to obtain better results in performance and exhaust emissions of CNG vehicles. The study includes experimental results which compare the power, efficiency, and emissions of modified CNG vehicles with respect to the previous ones with older systems. For this purpose, several bifuel CNG passenger cars of differents brands are used, which may run either on natural gas or gasoline. All the tests are done in a certified laboratory. The effects of each modifying parameter on power and emission are observed through experiments. The scientifical aspects of observed results are discussed. The future trend in this technology is illustrated.
Poster presentation: Resources and ecology