Effect of Free-Stream Flow Turbulence on Local Fleet Transfer in Turbine Nozzle Cascades.

Results of an experimental investigation of the effect of the degree of turbulence of free-stream flow on heat transfer in nozzle cascades are presented for Mach number and Reynolds number values M//c//1 less than equivalent to 1. 0, Re//c//1 less than equivalent to 6 multiplied by (times) 10**6. Two cascades of cylindrical nozzle blades with thickened leading edges characteristic of cooled blades were tested. To create higher turbulence, turbulizing nets were set up before the leading edges at varying distances. It is shown that an increase in the degree of the free-stream turbulence intensifies heat transfer in the leading edge region.