Experimental study on flow in diffuser of liquid-jet gas pump
Xiang Qingjiang1,2, Wang Chao3, Wu Yanlan1, Li Hong1
1.National Research Center of Pumps, Jiangsu University, Zhenjiang, Jiangsu 212013, China; 2.Department of Mechanical Enginee-ring, Inha University, Incheon 402-751, Republic of Korea; 3.Patent Examination Cooperation Jiangsu Center of the Patent Office, SIPO, Suzhou, Jiangsu 215011, China
Abstract：The liquid-jet gas pump has found its applications in jet aeration system and gas absorption etc. A study on the two-phase flow in diffuser of the pump is essential for the pump design and application. Thus, the pressure on the diffuser wall of a liquid-jet gas pump(LJGP)was measured by means of pressure sensors and the pressure recovery profile in the diffuser was obtained under various water working pressures and liquid-to-gas volumetric flow rate ratios. The LJGP was installed vertically; its diffuser and throat were made of Plexiglas. The results showed that the wall pressure recovery is in the range of about 2-5 kPa, the pressure profile drops initially then rises along the diffuser wall. Therefore, the effect of static pressure caused by the height of a vertical LJGP on flow in its diffuser needs to be taken into account. According to an analysis of flow in the diffuser, it was shown that the flow pattern has a great influence on its jet mixing characteristics; further the change in the location where the liquid-jet starts to mix with the gas can affect diffusing angle of the diffuser significantly. Particle image velocimetry(PIV)was used to map the liquid velocity in the diffuser, and the axial velocity distributions in cross-sections were obtained at two liquid-to-gas volumetric flow rate ratios. The results illustrated that the axial velocity is reduced by about 20%, and it was not uniform in cross-sections; the flow with high velocity has been deflected to one side wall in the diffuser at a low flow rate ratio.
向清江,, 王超, 吴燕兰, 李红. 液气射流泵扩散管内部流动试验研究[J]. 排灌机械工程学报, 2014, 32(7): 558-562.
Xiang Qingjiang,, Wang Chao, Wu Yanlan, Li Hong. Experimental study on flow in diffuser of liquid-jet gas pump. Journal of Drainage and Irrigation Machinery Engin, 2014, 32(7): 558-562.
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