INVESTIGATION OF COOLING PERFORMANCES AT THE GAS TURBINE BLADE CHANNEL
The cooling of the turbine blades in different parts of the turbine is carried out using different cooling techniques. Approximately 20% of the air produced in compressors is used in cooling systems. The air is sent into the wing through the internal channels. It travels through the outer profile of the wing and is vented through the far edge of the wing. The cooling process is then completed. Among the applied cooling techniques are internal cooling, surface air film forming, and jet impingement cooling techniques. Sometimes U-shaped cooling channels are utilized for internal cooling to take place in the wing.
An attempt to increase the cooling performance has been made with the utilization of wings (rips) at various angles. The change in the Nu number and the heat transfer coefficient on the channel surface as well as the impact of positioning 90° and 45° blades on a U-shaped 180° smooth (straight) channel on the cooling performance for three different Reynolds numbers (22000, 27500 and 33000) has been investigated experimentally using the method of liquid crystal thermography. The effect of the jet geometry, impact of the Reynolds number, velocity distribution within channels, and the heat transfer coefficient distributions are shown in the results.
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