離心泵的汽蝕現(xiàn)象
Centrifugal pump cavitation phenomenon
由于葉輪葉片入口附近液體壓力小于或等于液體輸送溫度下的飽和蒸汽壓力時(shí),液體就汽化,同時(shí)還可能有溶解在液體內(nèi)的氣體逸出,形成大量氣泡,氣泡隨液體流到葉道內(nèi)壓力較高處時(shí)又瞬時(shí)凝結(jié)潰滅。在氣泡凝結(jié)潰滅的瞬間,氣泡周圍的液體迅速?zèng)_入氣泡凝失形成的空穴,形成強(qiáng)大的局部高頻高壓水擊,金屬表面因疲勞而產(chǎn)生剝蝕。同時(shí),由于活潑氣體(如氧氣)的存在以及氣泡凝結(jié)時(shí)產(chǎn)生的局部高溫,導(dǎo)致金屬表面發(fā)生電化學(xué)腐蝕。上述這一過(guò)程稱為汽蝕現(xiàn)象。
As the impeller blades near the entrance to the liquid pressure is less than or equal to the liquid delivery temperatures of saturated steam pressure, the liquid will vaporize, and also may be dissolved in the liquid inside the escape of gas, the formation of large bubbles, bubbles with the liquid flow pressure in Tao Ye higher up the instantaneous condensation Shiyou Bubble Collapse. Condensation in the bubble Bubble Collapse of the moment, the bubble quickly burst into the fluid surrounding the bubble cavity formed by coagulation failure to form a strong local high-frequency high-pressure water hammer, the metal surface due to fatigue resulting from erosion. At the same time, due to active gases (such as oxygen), as well as the presence of air bubbles generated when the local condensation heat, resulting in electrochemical corrosion of metal surface. The phenomenon of this process is called cavitation. |