Laval喷管气体超声速凝结流动实验研究

Experimental study on gas supersonic condensation flow in laval nozzle

Laval喷管是超声速旋流分离技术的核心装置,气体在喷管内高速膨胀产生的低温效应可实现混合气体中可凝组分的冷凝分离。为明确喷管内超声速凝结流动规律,建立了超声速凝结流动实验系统,研究了Laval喷管内气体凝结流动过程,并重点对比分析了膨胀角为1.5°/3°/5°时喷管内的凝结流动参数。结果表明:气体在喷管内流动,温度压力不断降低,气体在喷管喉部处发生凝结,液滴数目急剧增长。喷管膨胀角对气体凝结过程影响明显。喷管膨胀角越大,喷管压力温度下降越快,喷管制冷效果越好。与此同时,凝结产生的液滴数目越多,半径越小。

Laval nozzle is the core device of supersonic cyclone separation technology.The low temperature effect of gas ex- pansion in the nozzle can achieve the condensation separation of condensable components in the mixed gas.In order to make clear the law of supersonic condensate flow in the nozzle,a supersonic condensation flow experimental system was established.The gas condensation flow process in the Laval nozzle was studied,and the condensation flow parameters in the nozzle at the expansion angles of1.5°/3°/5°were analyzed.The results show that the gas flows in the nozzle,the temperature and pressure are continu- ously reduced,the gas condenses at the throat of the nozzle,and the number of droplets increases sharply.The nozzle expansion angle has an obvious influence on the gas condensation process.The larger the nozzle expansion angle is,the faster the nozzle pressure temperature drops with a better cooling effect.At the same time,the condensation produces more droplets with smaller radius.