Analysis of a fuel spray subjected to coupled evaporation and decomposition

An analysis is made of a fuel spray whose evaporation rate decreases gradually due to liquid phase decomposition. The analysis is based on experimental results showing that the products of decomposition tend to nucleate and eventually form nonvolatile particular matter which is more difficult to burn. Although the details of both the decomposition rate and the mechanism of nucleation need to be further investigated, the experimental data can be used to illustrate the potential problem with decomposition. Decomposition in the liquid phase can cause a large reduction in combustion efficiency and an increase in the emission of particulate matter in the exhaust.