Abstract

Combustor-exit conditions in modern gas turbines are generally characterized by significant temperature distortions and swirl degree, which in turn is responsible for very high turbulence intensities. For this reasons combustor-turbine interaction studies have gained a lot of importance. Past studies have focused on the description of the effects of turbulence, swirl degree and temperature distortions on the behavior of the high pressure stages of the turbine, both considering them as separated aspects, and accounting for their combined impact. Concerning the external heat transfer coefficient, swirl and temperature distortions represent a severe challenge for the commonly adopted measurement techniques. The work presented in this paper was carried out on a non-reactive, three-sector test rig made by a non reactive combustor simulator and a nozzle guide vane cascade; it is able to create a representative combustor outflow, characterized by all the flow characteristics described before. A novel experimental approach, that was developed in a previous work, was exploited to experimentally retrieve the heat transfer coefficient and the adiabatic wall temperature distributions on a noncooled nozzle guide vane. The results allowed to evidence the effect of the inlet swirl on the heat transfer coefficient distribution, as well as the evolution of the temperature distribution on the vane surface moving through the cascade, constituting the first attempt to evaluate these aspects from a purely experimental point of view.

This content is only available via PDF.
You do not currently have access to this content.