Key factors affecting the cold start of diesel engines

Diesel engines are the versatile power source for passenger cars and commercial vehicles but have difficulties in engine cold start and idle stability. As the diesel engine combustion ignition depends upon the temperature at the end of the compression, the cold ambient conditions make the fuel ignition difficult and thus the engine start. When the ambient temperature drops to a very low level, it will further aggravate the cold start, idle stability and cold start emissions. The cold start performance of diesel engines depends upon a number of factors which can be classified into four categories; fuels properties, lubricants, engine geometry and fuel injection strategy. This review paper gives an insight into these factors and highlights the cold start aids in the modern engine design.