Tip-Timing Steam Turbine Rotor Blade Simulator

Background The traditional method of experimentally determining bladed disc vibration is with the use of strain gauges. The disadvantage of this method is the fact that only a few rotor stage blades can be measured, i.e. vibration data are limited to only a few blades. This problem led to the development of a different approach, one using the non-intrusive blade tip-timing technique. Methods Presented in this paper is a tip-timing simulator with one sensor in the casing and one in the shaft for a steam turbine rotor blade rotating up to 3000 rpm. Results The simulator results were compared with the experimental results of a 380-MW steam turbine. Conclusions The presented simulator gives only the blade vibration amplitudes instead of blade displacements. This approach can be applied to many other sensors. Simulators such as the one described above are able to replace costly physical experiments, verify any tip-timing system's operation and accuracy and serve as a very useful designing tool for the development of prototype tip-timing systems.