| 摘要 |
A downstream side fluid pressure is a fluid pressure of a fluid stagnation portion within a flow path that is internal to a regulator valve. A pressure ratio that is internal to the regulator valve is calculated from an upstream side fluid pressure, the downstream side fluid pressure, and a saturated vapor pressure for the fluid, calculated from a fluid temperature. A pressure ratio table that establishes relationships between a threshold value and a relative flow coefficient of the regulator valve, where the pressure ratio that is internal to the regulator valve, at the time at which the occurrence of cavitation within the regulator valve begins, is defined as the threshold value, is created and stored in a storing portion. The pressure ratio table is used to evaluate whether or not there is cavitation. |
