This experiment measures the temperature and the velocity field synchronously in the boundary layer in a rotating smooth, wall-heated channel using hot-wire. The Reynolds number based on the bulk mean velocity and hydraulic diameter is 19000 and the rotation numbers are 0, 0.07, 0.14, 0.21, 0.28 and 0.35. Four streamwise stations (X/D = 4.06, 5.31, 6.56, 7.81) were investigated. To calibrate the parallel-array hot-wire probe, a heating section is added to the original wind tunnel that could only calibrate the hot-wire at room temperature. Different gas temperatures at the outlet could be obtained by changing the heating power of the heating section. The velocity profiles and the temperature profiles are obtained. It can be seen that the viscous sublayer also exists when the wall is heated, thus the viscous sublayer profile method is also valid when the wall is heated. It is found that the velocity profile near the leading side is more sensitive to the change of rotation number and X/D than the velocity profile near the trailing edge. The critical rotation number phenomenon of velocity profile has also been found in present work. By comparing with the previous work without the wall heated, the influence of both kinds of buoyancy under this condition is discussed. Some explanations are given for the experimental results.

This experiment measured the instantaneous temperature and velocity field synchronously in nonisothermal turbulent boundary layer in a rotating straight channel with a parallel-array hot-wire probe. the Reynolds number based on the bulk mean velocity (U) and hydraulic diameter (D) is 19000, and the rotation numbers are 0, 0.07, 0.14, 0.21 and 0.28. The mean velocity u and mean temperature T as well as their fluctuating quantity u' and T' were measured at three streamwise locations (x/D = 4.06, 5.31, 6.56). A method for temperature-changing calibration with constant temperature hot-wire anemometers was proposed. it achieved the calibration in operational temperature range (15.5 °C-50 °C) of the hot-wire via a home-made heating section. The measurement system can obtain the velocity and temperature in a non-isothermal turbulent boundary layer at rotating conditions. The result analysis mainly contains the dimensionless mean temperature, temperature fluctuation as well as its skewness and flatness and streamwise turbulent heat flux. For the trailing side, the rotation effect is more obvious, and makes the dimensionless temperature profiles lower than that under static conditions. The dimensionless streamwise heat flux shows a linear decrease trend in the boundary layer. It is hoped that this research can improve our understanding of the flow and heat transfer mechanism in the internal cooling passages of turbine rotor blades.

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