Cascade

The effects of the swirling combustor exit flow on the high pressure nozzle guide vane dynamics shall be detemined using a level model combustor segment and a downstream positioned nozzle guide vane segment which equals a modern blading of a high pressure turbine. To improve the resolution of the measurement results and to get a realistic Reynolds number both the combustor segment and the nozzle guide vanes are used in an increased scale. The middle section of the model NGV is equipped with film cooling holes.

The measurement of the losses and the mixing of the film cooling air with the primary stream is done using a fiveholeprobe upstream and downstream of the casade section. The use of Particle Image Velocimetry, especially in the area of the combustor segment and the vane passage is also intended. Furthermore, the film cooling effectivity can be measured in the area of the nozzle guide vane. To do this, the Ammonia-Diazo technique developed by Friedrichs is used. The controlling of the test rig is realized using the software Lab View by National Instruments.

Primary Blower
Blower Type Radial Compressor
Performance 123 kW
Maximum Pressure Difference 0,22 bar
Maximum Volume Flow Rate 16200 m3/h
Secondary Blower
Blower Type Side Channel Blower
Wind Tunnel
Type Eiffel Tunnel with swirl generators and transparent measurement chamber
Operation Mode Suction mode
Measurement Chamber Cross Section 1200 mm x 200 mm
Velocity Range 2 m/s – 20 m/s

AG Turbo COORETEC:

The experiments with the CTI cascade wind tunnel will be done within the COORETEC 3.2.2 A “Interaction between Combustor and Turbine” research project in coorporation with Rolls-Royce Deutschland and MAN turbo.

Description:

The continuous reduction of fuel consumption of power stations, stationary gas turbines and flight engines is one of the most important aims of the industry from an economic as well as from an ecologic point of view. The demand for a better efficiency has resulted in a continuous impovement of the effectiveness of the single components. From a technological point of view it becomes more and more difficult to further raise the efficiency of the single components. It is certain that with the introduction of new technologies and concepts there will be further progress in raising the effectiveness of the seperate components but besides that, new ways of improving the whole efficiency of the gas turbine have to be found. In fact, the height of the efficiency strongly depends on how the seperate components interact. Because of that, it is most important to view the gas turbine in all, especially in the design process. The aim of the project is an experimental analysis of the interaction of the combustor swirl flow with the high pressure turbine nozzle guide vane. The swirl has a major influence on the aerodynamic losses of the nozzle guide vanes and the distribution and mixing of the cooling film. Because of the regard of the complex combustor outflow in the design process, an aerodynamic optimisation of the high pressure nozzle guide vanes and an improvement of the distribution of the cooling film will be possible. With that, an improved efficiency and a reduction of the CO2 Emissions will be achievable.