Measurement of Heat (Mass) Transfer Coefficient on the Blade Surfaces of a Linear Turbine Rotor Cascade With a Four-Axis Naphthalene Profile Measuring System

4-축 나프탈렌 승화깊이 측정시스템을 이용한 터빈 블레이드 표면에서의 열(물질)전달계수 측정

The heat (mass) transfer characteristics on the blade surface of a first-stage turbine rotor cascade for power generation has been investigated by employing the naphthalene sublimation technique. A four-axis profile measurement system is successfully developed for the measurements of the local heat (mass) transfer coefficient on the curved blade surface. The experiment is carried out at the free-stream Reynolds number and turbulence intensity of $2.09\times10^5$ and 1.2%. The results on the blade surfaces show that the local heat (mass) transfer on the suction surface is strongly influenced by the endwall vortices, but that on the pressure surface shows a nearly two-dimensional nature. The pressure surface has a more uniform distribution of heat load than the suction one.