Aerodynamic performance of a transonic turbine cascade at off-design conditions

The paper presents detailed measurements of the midspan aerodynamic performance of a transonic turbine cascade at off-design conditions. The measurements were conducted for exit Mach numbers ranging from 0.5 to 1.2. and for Reynolds numbers front 4 X 10(5) to 10(6). The profile losses were measured for incidence values of +14.5 deg. +10 deg, +4.5 deg. 0 deg, and -10 deg relative to design. To aid in understanding the loss behavior and to provide other insights into the flow physics, measurements of blade loading, exit flow angles, trailing-edge base pressures, and the axial velocity density ratio (AVDR) were also made. It was found that the profile losses tit transonic Mach numbers can be closely related to the base pressure behavior The losses were also affected by the AVDR.