Influence of temperature on erosion by a cavitating liquid jet

摘要

The influence of water temperature on cavitation erosion has previously been studied using a vibratory apparatus, but no researches have been conducted at a constant cavitation number in flow condition. This study deals with the influence of the water temperature on cavitation erosion using a cavitating jet apparatus. The optimum stand-off distance at 25℃ was 11, 15, 21 and 25 mm at cavitation number of a = 0.03, 0.025, 0.02 and 0.015, respectively, and was almost the same as that of a guideline in the ASTM G134 standard. The optimum stand-off distance at 75℃ is similar to that at 25℃. The erosion rate increases with the liquid temperature and reaches a peak, followed by a decrease. The relative temperature was defined as 0℃ for freezing temperature and 100℃ for boiling temperature of pressurized water. The peak appears at the approximate average of freezing and boiling relative temperatures. The erosion rate increases by 1%/℃ between 5 and 45℃ of relative temperatures, and decreases by 2%/℃ between 45 and 80℃.