Development And Commissioning Of A Purge Flow System In A Two Spool Test Facility

This paper presents the design, construction and the initial commissioning of a secondary air system, applied to a one and a half stage high pressure turbine test setup at the cold flow test facility in Graz University of Technology. The unique system can provide up to eight independent airflows to analyse engine realistic rim seals ejection or cooling injection for stator or rotor blades. This paper focuses on a specific test setup which used a total of four purge flows. These are used to purge the cavities around the high pressure turbine. While two flows enter upstream of the high pressure turbine, two enter downstream, with one flow at the inner and one at the outer wall of the flow channel, respectively. This paper primarily discusses the development and commissioning of the new facility. Initial five-hole probe measurement results are presented downstream of the high pressure turbine with and without any cooling injection. The outcomes of the first-time experiment depict the importance of the purge flow on the isentropic total to total stage efficiency.