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汽蚀是流体在流动过程中所发生的复杂现象,在水轮泵的运行中有着很大的影响,运行时所出现的汽蚀,破坏流体的正常流动,降低水轮泵的效率和材料遭受破坏。汽蚀现象的产生是:当水流在水轮机转轮中流过,到达转轮出口与吸出管进口处,往往出现负压和局部压力降低到水流的汽化压力,水就开始沸腾汽化,液体在汽化时产生蒸汽泡。加以自然界的水中,溶解有约5%的气体,当水汽化时,这些气体也从水中逸出而成气泡。这些气泡汇聚成群随着水流移至压力较高处,便骤然溃裂,此时,水流质点以高速度向汽泡中心撞击,这种撞击引起局部压力的增加(可达几十至几百个大气压),而被强烈撞击的水流质点遭到压缩后又向相反
Cavitation is a complex phenomenon that occurs during the flow of fluid and has a great influence on the operation of the water pump. The cavitation that occurs during operation corrupts the normal flow of the fluid and reduces the efficiency and materials of the water pump damage. Cavitation phenomenon is generated: When the water flow in the turbine runner to reach the runner exit and suction pipe inlet, there is often a negative pressure and partial pressure is reduced to the flow of vaporization pressure, the water began boiling boiling vapor in the liquid Generate steam bubbles. To the nature of the water, dissolved about 5% of the gas, when the water vaporized, these gases also escape from the water into a bubble. These bubbles converge into groups with the water flow to a higher pressure, they suddenly burst, at this time, the water particles at high velocity impact center of the bubble, this impact caused by an increase in local pressure (up to tens to hundreds A barometric pressure), while the highly impacted water mass is compressed and then reversed