水气比对射流预冷喷射特性影响的数值研究

Numerical Simulation for Effects for Water/Air Ratio on Injection Characteristics with Water Injection Pre-Compressor Cooling

关键词:  计算流体力学  水气比  蒸发特性  温度分布  冷却

Key words:  Computational fluid dynamics  Water air ratio  Vaporization Characteristics  Temperature distribution  Cooling

摘要:

为了研究水气比对以液态水为喷射工质的射流预冷喷射特性的影响，选取了适合的计算和求解方法，建立了研究射流预冷喷水特性计算的数学模型。采用该模型对喷射腔室中的三维两相流场进行了数值计算，并通过与已有的试验结果进行了对比，最大相对误差不超过3%，验证了模型的正确性。最后对水气比对于喷射特性的影响进行了数值模拟，并计算得到了完全蒸发距离，其中水气比0.03时的完全蒸发距离为10倍喷水腔室内径，结果表明，随着水气比的增加，出口截面的液态水蒸发量上升，蒸发率和截面平均总温下降，完全蒸发距离增加。

Abstract:

In order to investigate the effects of water/air ratio on injection characteristics of liquid water for Water Injection Pre-Compressor Cooling(WIPCC)，a numerical model incorporating the physical properties calculation method was developed for studying injection characteristics. The model was then employed for three-dimension numerical investigations of two-phase flow for the injection of liquid water into high speed airflow. The calculated results were compared and validated against the available test data，and the maximal relative error was not more than 3%，showing a good agreement. The effects of the water/air ratio on injection characteristics were also studied with the numerical model and the absolutely vaporization distance was calculated. The absolutely vaporization distance was 10 times the inner diameters of the injection chamber at water/air ratio 0.03. It was concluded that，with the increase of the water/air ratio，the vaporization ratio and temperature at exit dropped gradually，whereas the vapor mass flow rate and absolutely vaporization distance at exit increased gradually.