Study of Tip Clearance Measurement System Using a Fixed Discharge Probe

• Published in: Nihon Kikai Gakkai rombunshuu. B hen Vol. 62; no. 598; pp. 2290 - 2295
• Main Authors: WATANABE, Takayuki, MATSUKI, Masakatu
• Format: Journal Article
• Language: Japanese
• Published: The Japan Society of Mechanical Engineers 1996
• Subjects: Spark Discharge
• ISSN: 0387-5016; 1884-8346
• DOI: 10.1299/kikaib.62.2290

We have devised a new method for tip clearance measurement which does not require an actuator to move the discharge probe. The applications of this method and its characteristics were investigated, and tip clearance measurements were attempted. As a result, it was found that UV irradiation was indispensable for obtaining a constant discharge voltage in the range of 98kPa∼196kPa. The discharge characteristics varied with pressure, but a linear relationship could be obtained. The discharge characteristics varied with the shape of the rotor. Hence, this factor must be checked prior to measurement. The probes produced were not affected by the peripheral velocity of up to 80m/s. Measurement accuracy using a core-type probe was within ±0.05mm, and with a cylinder-type was within ±0.lmm. The cylinder-type probe was able to measure the tip clearance up to a peripheral velocity of 270m/s.