A Simplified-Model Approach to Group Combustion of Fuel Spray

Combustion of a liquid fuel spray distributed in a uniform stream was analyzed with a distributed source model. In this model, each fuel droplet of the spray is expressed mathematically by the moving source, of which the strength is to be determined by the relevant governing equations and boundary conditions. The main equation is an integral equation which expresses the inter- relation among strengths of fuel droplets in the spray. Given the assumptions of a uniform velocity of the stream and zero-relative velocity of fuel droplets, the spatial variation of the droplet radii can be expressed by a differential equation with respect to a spatial coordinate y.

Thus, the set of coupled equations can be solved numerically and iteratively. Then nature of the distributed spray combustion in the convective flow is seen to be governed by two non-dimensional parameters, known to be group combustion numbers.