Investigation of Combustor-Turbine-Interaction in a Rotating Cooled Transonic High-Pressure Turbine Test Rig: Part 1 — Experimental Results

Abstract

Within the scope of European Commission FP7 project FACTOR, dedicated to combustor-turbine-interaction research, a clean-sheet design of a rotating turbine test rig featuring a non-reacting combustor simulator was created and built among the partners. German Aerospace Center DLR provided the operational facility NG-Turb to which the rig was adapted and was responsible for global rig integration and operation, also including aerodynamic probe measurements of the flow field. The rig and experimental set-up is described and post-processed results from probe traverses in several measurement planes are presented and discussed. Special attention is paid to the comparison and influence of two combustor-NGV clocking positions on the periodic turbine flow field, made possible by rig adaptation during the campaign. The strongly distorted and nonuniform turbine inlet flow created by the combustor simulator proved challenging for the probe measurements, but at the same time set a realistic boundary condition enabling the analysis of ‘CTI’ by flow structures migrating through the blade rows.

Unsteady Flows and Component Interaction in Turbomachinery

“…Koupper et al [91], Bacci et al [165,166], Koupper et al [167], Krumme et al [168], and Gövert et al [169] developed an engine-representative combustor simulator dedicated to reproducing the expected turbine inlet profiles in terms of stagnation pressure, stagnation temperature, and flow field within the "Full Aerothermal Combustor-Turbine interactiOns Research" (FACTOR) project co-funded by the European Commission. The aims of the project were to develop both a trisector to be tested at the University of Florence (Florence, IT) and a full annular rig to be tested at DLR in Göttingen (DE).…”

“…However, in the ducted configuration, LES and HWA agreed well with the timescale maps, and continuously increasing computational capabilities will help reduce local errors by means of a higher number of through flows. Based on the activity carried out on the trisector, the rotating rig was designed and manufactured and its main characteristics are described by Krumme et al [168], where the main issues that were overcome are also reported. Gövert et al [169] also performed an integrated simulation of the annular rig, even though only a sector of 18 • was considered thanks to the periodicity of the configuration, thus using a computational domain similar to the one used by Koupper et al [170].…”

“…WCTF (Warm Core Turbine Facility) [181,182] LSRR (Large Scale Rotating Rig) [183] TATEF (Turbine Aero-Thermal External Flows) & TATEF2 [34,37,38,184] RTBDF at Gas Turbine Laboratory (MIT, Cambridge, MA, USA) [185] TRF (Turbine Research Facility) at Air Force Research Laboratory (AFRL) [53,186] SILOET (Strategic Investment in Low-carbon Engine Technology) [19] TTF (Turbine Test Facility) [55,187] LEMCOTEC (Low Emissions Core-Engine Technologies) [87,188] OTRF (Oxford Turbine Research Facility) [85,86] FACTOR (Full Aerothermal Combustor-Turbine interactiOns Research) [91,[165][166][167][168] ECAT (Engine Component Aerothermal Facility) [160,161] STech (Smart Turbine Technologies) [79] Most of the temperature distortions were in the range 0.73 < T/T < 1.21 except the LSRR case, which was characterized by a wider temperature interval 0.68 < T/T < 2.0. Among the listed ones, the most recent facilities were also the more representative of modern lean-burn combustors.…”