METHOD OF MEASURING NON-STEADY HYDRODYNAMIC FORCE ACTING ON CASCADE AND VIBRATOR USED FOR METHOD OF MEASURING NON-STEADY HYDRODYNAMIC FORCE ACTING ON CASCADE

摘要

PROBLEM TO BE SOLVED: To provide a method of measuring a non-steady hydrodynamic force acting on a cascade, capable of accurately measuring the hydrodynamic force acting on an entire blade surface including a blade height direction without using a pressure sensor for measuring the hydrodynamic force.;SOLUTION: A holding portion is provided in each of a vibration blade and stationary blades in a cascade of blades, a vibrator is provided in the holding portion of the vibration blade, a gap sensor detecting a displacement of the vibration blade is provided to be proximate to the holding portion of the vibration blade, a strain gauge detecting a strain of the vibration blade is provided in a spring portion supporting the holding portion of the vibration blade, the vibrator is driven to vibrate the vibration blade and a vibration frequency for vibrating the vibration blade is changed, a vibrating force of the vibration blade is computed on the basis of the strain of the vibration blade detected by the strain gauge, a frequency for vibrating the vibration blade is computed on the basis of the displacement of the vibration blade detected by the gap sensor, values of the displacement/vibration force are computed on the basis of the detected displacement of the vibration blade and the computed vibration force of the vibration blade, and a non-stationary hydrodynamic force acting on the vibration blade and the stationary blades is computed on the basis of these computed values.;SELECTED DRAWING: Figure 9;COPYRIGHT: (C)2016,JPO&INPIT