EFFECTS OF ENTRAINED AIR MANNER ON CAVITATION DAMAGE

• Published in: Journal of hydrodynamics. Series B Vol. 23; no. 3; pp. 333 - 338
• Main Authors: WU, Jian-hua, LUO, Chao
• Format: Journal Article
• Language: English
• Published: Singapore Elsevier Ltd 01.06.2011; Springer Singapore; College of Water Conservancy and Hydropwer Engineering, Hohai University, Nanjing 210098, China
• Subjects: air entrainment; air pressure; air tube area; Cavitation; cavitation damage; Damage; Dams; Engineering; Engineering Fluid Dynamics; entrained air manner; Entrainment; Fluid dynamics; Fluid flow; Hydrodynamics; Hydrology/Water Resources; Numerical and Computational Physics; Simulation; Tubes; 几何参数; 应用程序; 水力参数; 破坏控制; 空气压力; 空气夹带; 空气管; 空蚀破坏; entrained air manner; air entrainment; air tube area; air pressure; cavitation damage
• ISSN: 1001-6058; 1878-0342
• DOI: 10.1016/S1001-6058(10)60120-5

Early in 1953 the experiments by Peterka proved that air entrainment has effects on decreasing cavitation damage. This technology has been widely used in the release works of high dams since the inception of air entrainment in the Grand Goulee Dam in 1960. Behavior, mechanism and application of air entrainment for cavitation damage control have been investigated for over half century. However, severe cavitation damage happened due to complex mechanism of air entrainment. The effects of air entrainment are related to many factors, including geometric parameters, hydraulic parameters and entrained air manners. In the present work an experimental set-up for air entrainment was specially designed, the behavior of reducing cavitation damage was experimentally investigated in the three aspects of entrained air pressure, air tube aera and air tube number. The results show that magnitude of reduction of cavitation damage is closely related to the entrained air tube number as well as entrained air pressure, air tube aera, and that the effect through three air tubes is larger than that through single air tube although the entrained air tubes have the same sum of tube aera, that is, 1 ＋ 1 ＋ 1 〉 3. Therefore, it is important to design an effective manner of air entrainment.