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| Cavitation in pipes with different length-diameter ratios and inclination angles |
| Du Huiyong, Zhang Qingfeng, Liu Jianxin, Wang Zhancheng, Li Min, Xu Bin |
| Vehicel & Transportation Engineering Institute, Henan University of Science and Technology, Luoyang, Henan 471003, China |
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Abstract Cavitation phenomenon in pipes with different length-diameter ratios and inclination angles is investigated. The cavitating flows in the pipes with 5 ∶1, 5 ∶2 length-diameter ratios, and 90°, 120°, 135° inclination angles are simulated under 0.3, 0.5, 1.0 MPa inlet pressure, respectively. The pressure and cavity contours are obtained. The simulation results show that all the cavity appears at the inlet of pipe. Under the same pressure differential across the pipe, the cavity size and intensity are shrunk and reduced with the increasing pipe diameter. Cavitation effect is remarked at 90° inclination angle, particularly a cavity appears each on the top and bottom of the pipe inlet edge. With the increasing inclination angle, the cavitation effect is weakened and the cavity size decreases; further it occurs at the bottom of the pipe inlet edge only. Meanwhile a few cavitation visualization experiments are carried out, indicting the numerical simulation results agree very well with the observations.
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Received: 20 March 2014
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