Development and performance evaluation of a photography system for measurement of steam turbine blades

This paper presents the effective photography system for the material development of steam turbine blades. By using the proposed system, the image of the turbine blade under high-speed rotation can be visualized. To measure the rotational angle of the blade, a rotary encoder is employed. Since the jitter of electronic circuits increases due to the use of the encoder, a digital pulse generator is included in the photography system. Moreover, a timing controller is used to synchronize the timing of all components in the photography system. Experimental results show that the strain due to the stress applied to the turbine blade is visualized under the condition of high temperature and high speed rotation.