A large-scale high pressure and temperature air system to enable representative metal effectiveness in multiple gas turbine facilities

Conference item

This paper details the design of a 1 MW compressed air system and infrastructure upgrade to supply heated air at 327°C (600 K) and 50 barg to two world-leading gas turbine test rigs: the Oxford Turbine Research Facility (OTRF) and the Engine Component Aero Thermal (ECAT) facility. These are two established, high technology readiness level (TRL) facilities for high pressure turbine research and have been constantly developed over 40 years. This high temperature air supply system represents the latest such development program. The motivation for this is to reduce the development time for novel gas turbine cooling technology, by providing complimentary test facilities with a high degree of engine similarity that can evaluate component thermal performance before committing to expensive full-scale engine testing.

The new air supply system enables both facilities to match engine mainstream-to-coolant temperature ratio with run times over 60 seconds, in addition to previously matched Reynolds number, Mach number, combustor temperature, swirl and turbulence profile. The new air supply system consists of four air storage tanks with a total volume of 136m3, three of which are electrically trace heated across 23 individually PID controlled zones. The system heat-up time is 29 hours from ambient and the final temperature stability is better than 5 °C/hour. Up to three liquid-cooled multistage reciprocating compressors deliver 2400 sm3/hr at 50 barg. Desiccant dryers remove water vapour to -30 °C and oil content is reduced to less than 0, 01 mg/m3 at 20°C. A single 300 kW inline electric heater raises the air temperature from 35 °C to 327 °C before entering the storage tanks. The connecting pipework is designed to accommodate nozzle loadings imposed during 8 different operating configurations, depending on whether individual tanks are heated or operated at ambient temperature. The discharge from the tanks feeds one facility at a time, through 8” NB flanged pipework that is also trace heated and maintained at the setpoint. Traceable critical flow venturi nozzles provide flow rate measurements up to 30 kg/s dry air (at 327°C) with an accuracy better than 0.5 % actual reading. Details are provided on the overall system design, the commissioning tests and performance measurements of the flow metering system.

Authors: Goodenough, J; Messenger, A; Beard, PF

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Euroturbo
• Journal: Conference Proceedings Repository
• Article number: ETC2023-172
• Publication date: 2023-10-28
• Acceptance date: 2023-02-19
• Event title: 15th European Conference on Turbomachinery Fluid dynamics & Thermodynamics
• Event location: Budapest, Hungary
• Event website: https://etc15.eu/
• Event start date: 2023-04-24
• Event end date: 2023-04-28
• DOI: 10.29008/ETC2023-172
• EISSN: 2410-4833
• ISSN: 2313-0067
• Language: English
• Keywords: metal effectiveness; test; facility; design; turbine; aerothermal