スワールノズルの過熱水噴霧の微粒化特性

抄録

Atomization characteristics of superheated water jet sprayed from a swirl nozzle were experimentally investigated with the immersion method which captures atomized water droplets into a sampler filled with silicone oil. The spay nozzle is used for a water / liquid nitrogen rocket engine (WNE) that utilizes the vapor pressure of nitrogen evaporation as a thrust source when the heat is supplied from superheated water by mixing these two propellants in a mixing chamber. The effects of the parameters such as superheated water temperature and injection pressure on the Sauter mean particle diameter (SMD) and particle size distribution were investigated. The results indicated that the SMD decreased as the temperature increased. Compared to the fan spray nozzle at the same flow rate, the swirl nozzle was found to be able to obtain the same or lower SMD at any dimensionless degree of superheat, suggesting that the swirl nozzle can improve the performance of this engine.