通气参数对水下两相冲压式发动机内推力影响的数值模拟研究

Effect of aeration parameter on inner thrust of underwater two-phases ramjet

排水下两相冲压式发动机是基于泡状两相流在Laval喷管中运动的理论开发的一种新型发动机。采用CFD数值分析的方法对水下两相冲压式发动机的工作机理进行了初步的研究。在定常流动工况下,不考虑空气的可压缩性和热交换,设来流速度和通气角度不变,得到了发动机内推力随通气参数变化的规律。通气速度为超音速的情况下,得到发动机的内推力随着通气速度的增大而增大,但是当通气速度达到一定范围时,发动机的内推力波动较大。通入单一空气时,温度对发动机内推力几乎没有影响。通入的空气体积流量不变且其中含有水蒸汽时,空气的湿度越大,发动机内推力就越小。

The underwater two-phases ramjet is one kind of new style jets which are based on the development of two phases bubbly flow throughout Laval nozzle. The working mechanism of ramjet was studied numerically by using CFD commercial software FLUENT 6.2. The steady flow, non-compressible air and non-exchanging heat were concerned. When the aeration speed is supersonic and keeping the velocity of ship and the aeration angle is steady, the inner thrust of the ramjet increases as the aeration speed increases. The inner thrust fluctuates in a wide range when the aeration speed increases to certain high level. When the pure air is aerated, the temperature of the air almost doesn't have effect on the inner thrust. When the gas aerated is composed of air and vapour, and the volume flux of the gas remains invariable, the increase of gas humidity will cause a drop of the inner thrust of the underwater two-phases ramjet.