空气中逸散水蒸气传热及相变过程的行为研究

针对航母舰载机蒸汽弹射器滑道逸散水蒸气的传热与凝结现象，建立空气/水蒸气/凝结水三流体的流动、传热及相变过程数学模型。其中具有描述水蒸气复杂过程热力学行为的IAPWS模块以自定义程序并入模型中，利用Eulerian-Eulerian模型加入质量传递、能量传递和动量传递方程来实现水蒸气流动过程中传热传质问题的研究；在质量传递模型中加入液滴成核和生长理论模型，研究水蒸气的凝结过程。结果表明:在流动过程中，空气-水蒸气-液态水三流体混合，温度逐渐趋于一致；进气道入口压力越低，发动机对水蒸气的吸入量越大；伴随空气流动的水蒸气温度不断下降，并且会因有凝结现象发生；随着空气来流速度的增加，水蒸气的吸入量也会呈现先增加后下降的趋势；随着水蒸气流速的提高，水蒸气进气量上升，空气所占比例有所下降，但仍然是主导地位。 

Heat transfer and condensation of overflow steam in air

For the heat transfer and condensation of overflow steam in the aircraft steam catapult, a mathematical model was developed to understand the three-fluid flow with the air, steam and condensation water. The module of thermodynamics international association for the properties of water and steam (IAPWS) was incorporated into model system by self-developed user defined function (UDF) code. Eulerian-Eulerian model was used to solve the three fluid flow, exchange of mass, momentum, and energy was included into model equations, moreover, nucleation and growth of liquid droplet were added into mass transfer. Result showed that the mix of the air, steam and condensation water caused the temperature homogenization. Suction volume of steam increased with the decrease of inlet pressure of engine. The condensation phenomena happened with the decrease of steam temperature, and condensation water occurred. Suction volume of steam increased first and then decreased with the increase of air velocity. With the increase of steam velocity, the suction volume of steam increased and the air proportion decreased.