| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To diagnose the presence/absence and state of cavitation while reducing time and efforts required for preparing data. <P>SOLUTION: A cavitation diagnosis apparatus comprises a diagnostic coefficient calculation section 7 which calculates a diagnostic coefficient from an upstream-side fluid pressure P1 of a control valve 1, a downstream-side fluid pressure P2, and a fluid pressure P3 in the middle of recovery from a pressure loss caused by the control valve 1, a storage section 8 which stores therein a threshold valueσth0 that is the diagnostic coefficient when starting generating cavitation, a threshold valueσth1 that is the diagnostic coefficient in the case where a state meeting a condition of a characteristic pressure ratio XFz is reached, a threshold valueσth2 that is the diagnostic coefficient in the case where a state of critical cavitation is reached, and a threshold valueσth3 that is the diagnostic coefficient in the case where a choke-flow state is reached, and a determination section 9 which calculates the threshold valuesσth0,σth1,σth2 andσth3 corresponding to the relative capacitance coefficient of the control valve 1 and determines the presence/absence and state of cavitation in comparison with the calculated diagnostic coefficient. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
