Natural gas is a promising alternative fuel to petrol for vehicles. However, one of the factors hampering the design of natural gas burning engines for domestic cars is the long delay from the time of ignition to the commencement of significant heat release. This is mainly due to the substantially endothermic phase during the early development of the combustion in natural gas. It is well known that high-energy, extended or multiple ignition sources can reduce this problem. The present article uses a large-scale computer simulation of a natural gas engine to examine the issues affecting the optimization of such ignition sources.
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