放電式翼端すきま測定法の研究

抄録

Trial manufacture of a tip clearance measurement system with spark discharge has been conducted, through which the structure of this apparatus was clarified. The characteristics of spark gap between the probe and the blade that determines the measurement accuracy of this apparatus and the effect of UV irradiation were investigated. As a result, the measurement value was affected significantly by voltage which is one of the factors of the spark discharge law (Paschen's law) . When supply voltage is more than 900 V, the scatter of measurement value increases. However, this scatter, obtained when ultraviolet irradiation was used, was found to remain in the initial range of the minimum spark discharge voltage, and the spark gap corresponding to supply voltage was also observed to approximate the Paschen curve. The measurement value was affected by the shape of the blade, but the spark gap was observed to approximate the Paschen curve when ultraviolet irradiation was used. The peripheral velocity of the rotor within 140 m/sec did not affect the measurement value.