Bergles Symposium
Effects of Blade Profile on Turbine Blade Heat (Mass) Transfer
R. J. Goldstein, E. R. G. Eckert, H. P. Wang and S. J. Olson
Process, Enhanced and Multiphase Heat Transfer
A Symposium in Honor of Professor Arthur E. Bergles
Georgia Institute of Technology
Atlanta, Georgia, November 16, 1996.
Abstract
The effects of turbine blade profile on the development of secondary flows and heat transfer in turbine blade passages are discussed based on flow visualization and naphthalene mass transfer measurements in linear cascades. Two blade profiles are examined in the central span, where the flow is two-dimensional, and near the endwall, where secondary flows develop. From the results a comparison of the global secondary flow fields can be made. While the blade profiles are quite different, there are striking similarities in the secondary flow field. For both blades, a passage vortex system develops which strongly affects the magnitude of heat/mass transfer coefficients on the suction surface near the endwall. The mass transfer coefficient distribution in this region is explained with support from the flow visualization results. Although the variation of mass transfer coefficients on the blade surface are similar for the two blades, the magnitude of the mass transfer coefficients is different and is attributed to the strength of the secondary flow in the passage.
Steve Olson (sjo@me.umn.edu)