NUMERICAL-ANALYSIS OF CONVECTING, VAPORIZING FUEL DROPLET WITH VARIABLE PROPERTIES

Detailed analysis of a cold fuel droplet suddenly injected into a hot gas stream is examined. The effects of variable thermophysical properties, transient heating and internal circulation of liquid, deceleration of the flow due to the drag of the droplet, boundary-layer blowing, and moving interface are included. Several parametric studies are performed by changing the following quantities: initial droplet temperature, ambient temperature, initial Reynolds number, fuel type, and droplet heating model. The results show that for higher transfer numbers, the vaporization rate is larger and the drag coefficient is significantly reduced mainly due to a large reduction in friction drag. For lower transfer numbers, the boundary-layer blowing effect is weaker and the drag coefficient is dominated by the Reynolds number only. The results also indicate that the constant-property calculation overestimates the drag coefficient.