Spray cooling is considered to be one of the most promising electronic cooling methods, since it has several unique advantages such as high heat dissipation, small fluid inventory, and uniformity of heat removal. However the spray cooling performance could be further improved, which can be expressed by the combination of a better heat removal capability, a higher cooling efficiency, and the more uniform surface temperature distribution. In this paper, recent research developments on spray cooling characteristics under different working conditions are reviewed, possible approaches to improve the spray cooing performance are also proposed. Especially spray cooling systems with both enhanced surface and lower system pressure would be be full of attraction.

The mathematical and physical model of the liquid propellant spray in straight nozzle was proposed for studying the performance characteristics of the small-scale liquid rocket engine. With the Fluent software, the numerical simulation was carried out. Sauter mean diameter (SMD) of the HAN-based liquid propellant (LP1846) in the engine combustor changing with spray pressure, nozzle diameter and the liquid surface tension were analyzed. The results indicate that: in the spray pressure region of 1.8MPa~3.0MPa, at a fixed spray pressure, the smaller is the nozzle diameter, the smaller is the droplets’ SMD and the relationship between the SMD and the nozzle diameter is approximately linearity; for the same nozzle diameter and spray pressure, the larger is the surface tension, the larger is the liquid droplets’ SMD.