Detailed film cooling measurement for a gas turbine blade with air and CO2 injection /
A transient liquid crystal technique is developed to measure the detailed heat transfer coefficient and film effectiveness distributions for a linear gas turbine blade cascade under the effects of mainstream Reynolds number, free-stream turbulence intensity, upstream unsteady wake, trailing edge coo...
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
1996.
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| Subjects: | |
| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=739667571&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | A transient liquid crystal technique is developed to measure the detailed heat transfer coefficient and film effectiveness distributions for a linear gas turbine blade cascade under the effects of mainstream Reynolds number, free-stream turbulence intensity, upstream unsteady wake, trailing edge coolant ejection, and film injection. The experiments are performed on a five-blade linear cascade in a low-speed wind tunnel facility. The test blade coated with liquid crystals is located at the middle of the blade cascade. The exit Reynolds number based on the blade axial chord and cascade exit velocity is varied from 5.3 x 10[] to 7.6 x 10[]. Higher turbulence intensity is generated with a turbulence grid upstream of the blade cascade. Unsteady wakes are produced using a spoked wheel-type wake generator located between the linear cascade and the turbulence grid. Upstream trailing edge ejection is simulated using coolant holes located in the hollow spokes of the wake generator. The mass flux ratio of the jets to the free-stream is varied from 0.0 to 1.0. Seven rows of film holes on the turbine blade are used to simulate the film cooling injection. Film blowing ratio is varied from 0.4 to 1.2 by controlling the flow rate of the coolant, and the coolant-to-mainstream density ratio is varied from 1.0 to 1.5 by using air and C02 as injectants. The results show that the transient liquid crystal technique provides detailed film cooling heat transfer information on the blade surface which is very useful to gas turbine blade design. The present spanwise-averaged results are in good agreement with results obtained for a similar blade using thin foil-thermocouple technique for smooth surface blade. It is found that mainstream Reynolds number, free-stream turbulence intensity, upstream unsteady wake, trailing edge coolant ejection, and film injection are all important factors that affect the blade surface heat transfer distributions. |
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| Item Description: | Vita. "Major Subject: Mechanical Engineering". In title, subscript numerals are used. |
| Physical Description: | xvi, 143 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilms Inc. |
| Bibliography: | Includes bibliographical references: pages 129-136. |