Gas-to-blade convection heat-transfer coefficients were obtained on a forced-convection, water-cooled, single-stage aluminum turbine over a range of gas-flow Reynolds numbers and inlet-gas temperatures at several computed gas-flow inlet angles. Radiation to the blades was negligible. The convection coefficients were obtained for the nominal-design gas-flow inlet angle of 37° over a range of gas-flow Reynolds numbers from 30,000 to 110,000 and for a limited Reynolds number range at computed inlet angles of 25°, 43°, and 49°. The range of inlet-gas temperatures covered was from 250° to 1250° F.nGas-to-blade convection coefficients were correlated at each inlet angle by the general relation for forced-convection heat transfer that expresses Nusselt number as a function of Reynolds and Prandtl numbers. The root-mean-square deviation of the data from the correlation curve obtained at the nominal-design gas-flow inlet angle of 37° was 5*1/2 percent.nIndividual gas-to-blade convection heat-transfer correlation curves resulted from turbine operation at several gas-flow inlet angles. As the computed inlet angle was increased from 25° to 43°, the gas-to-blade heat-transfer rate increased an average of 34 percent for the range of Reynolds numbers considered.nThe correlation curve for the data obtained at the 37° gas-flow inlet angle was compared with those from static-cascade results for impulse blades and showed agreement within 9 percent. From the agree¬ment between the experimental and computed gas-to-blade heat-transfer results, theory may be used to compute the gas-to-blade convection heat-transfer correlation for this turbine configuration at the design gas-flow inlet angle.
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