Session: 38-05 Gas Turbine Engine Transition Ducts and Flow Interactions II

Paper Number: 82449

82449 - Experimental Investigation of an Aggressive S-Shaped Intermediate Compressor Duct 

Reducing the fuel consumption of airplanes is one of the main research topics of the aero industry. Due to this, the bypass ratio in modern aero engines is increasing and the radial offset between the low pressure compressor (LPC) and the high pressure compressor (HPC) is getting larger. Motivated by shortening the length of the duct between the LPC and HPC, called the intermediate compressor duct (ICD), a workgroup from DLR Institute of Propulsion Technology, MTU Aero Engines and GKN Aerospace set up a measurement series in the new DLR ring cascade wind tunnel, that simulates a shorter and therefore aerodynamically more aggressive s- shaped ICD. The setup consists of an full annulus channel. It provides 60 swirler blades, 120 HPC outlet guide vanes (OGV), 10 struts and 30 LPC inlet guide vanes (IGV). Behind the OGV, there is a bleed air outlet which can be varied between 3% and 35% of the mass flow. This paper describes the highly instrumented test rig and its measurement techniques. Following investigations can be performed in the rig: determination of flow velocities and angles, performance behavior, pressure losses, temperatures, local total pressures and local Mach numbers, pressure fluctuations, turbulence level, particle image velocimetry, laser two focus measurements and oilstreak pattern. Seven different measurement planes are available. The paper presents the results of multi-hole probes, total pressure rakes, temperature rakes and hotwire measurements. The tests are conducted at eight different operating points, varying in Mach number, Reynolds number, bleed rate, angle of swirler and angle of HPC IGV. The high number of measurements leads to a profound understanding of the behavior of the ICD. The resulting conclusion is that in spite of the reduced axial length the flow through the aggressive s-shape of the ICD is without separation and therefore the desired performance is archived.

Presenting Author: Aaron Kasper DLR German Aerospace Center

Presenting Author Biography: 2006-2013: University of Apllied Science FH Aachen Germany<br/>2014-2016: Porsche AG Germany<br/>2016-today: DLR Cologne Germany

Authors:

Aaron Kasper DLR German Aerospace Center
Marcus Lejon GKN Aerospace Sweden AB
Thomas Dygutsch German Aerospace Center DLR, Institute of Propulsion Technology
Sebastian Grund German Aerospace Center DLR, Institute of Propulsion Technology
Manfred Beversdorff German Aerospace Center DLR, Institute of Propulsion Technology
Sebastian Hakansson German Aerospace Center DLR, Institute of Propulsion Technology
Eberhard Nicke German Aerospace Center DLR, Institute of Propulsion Technology