A Comparison of Cylindrical and Fan-Shaped Film-Cooling Holes on a Vane Endwall at Low and High Freestream Turbulence LevelsSource: Journal of Turbomachinery:;2008:;volume( 130 ):;issue: 003::page 31007DOI: 10.1115/1.2720493Publisher: The American Society of Mechanical Engineers (ASME)
Abstract: Fan-shaped film-cooling holes have been shown to provide superior cooling performance to cylindrical holes along flat plates and turbine airfoils over a large range of different conditions. Benefits of fan-shaped holes include less required cooling air for the same performance, increased part lifetime, and fewer required holes. The major drawback, however, is increased manufacturing cost and manufacturing difficulty, particularly for the vane platform region. To this point, there have only been extremely limited comparisons between cylindrical and shaped holes on a turbine endwall at either low or high freestream turbulence conditions. This study presents film-cooling effectiveness measurements on an endwall surface in a large-scale, low-speed, two-passage, linear vane cascade. Results showed that film-cooling effectiveness decreased with increasing blowing rate for the cylindrical holes, indicating jet liftoff. However, the fan-shaped passage showed increased film-cooling effectiveness with increasing blowing ratio. Overall, fan-shaped holes increased film-cooling effectiveness by an average of 75% over cylindrical holes for constant cooling flow.
keyword(s): Flow (Dynamics) , Cooling , Turbulence AND Coolants ,
|
Collections
Show full item record
| contributor author | W. Colban | |
| contributor author | K. A. Thole | |
| contributor author | M. Haendler | |
| date accessioned | 2017-05-09T00:30:46Z | |
| date available | 2017-05-09T00:30:46Z | |
| date copyright | July, 2008 | |
| date issued | 2008 | |
| identifier issn | 0889-504X | |
| identifier other | JOTUEI-28748#031007_1.pdf | |
| identifier uri | http://yetl.yabesh.ir/yetl/handle/yetl/139480 | |
| description abstract | Fan-shaped film-cooling holes have been shown to provide superior cooling performance to cylindrical holes along flat plates and turbine airfoils over a large range of different conditions. Benefits of fan-shaped holes include less required cooling air for the same performance, increased part lifetime, and fewer required holes. The major drawback, however, is increased manufacturing cost and manufacturing difficulty, particularly for the vane platform region. To this point, there have only been extremely limited comparisons between cylindrical and shaped holes on a turbine endwall at either low or high freestream turbulence conditions. This study presents film-cooling effectiveness measurements on an endwall surface in a large-scale, low-speed, two-passage, linear vane cascade. Results showed that film-cooling effectiveness decreased with increasing blowing rate for the cylindrical holes, indicating jet liftoff. However, the fan-shaped passage showed increased film-cooling effectiveness with increasing blowing ratio. Overall, fan-shaped holes increased film-cooling effectiveness by an average of 75% over cylindrical holes for constant cooling flow. | |
| publisher | The American Society of Mechanical Engineers (ASME) | |
| title | A Comparison of Cylindrical and Fan-Shaped Film-Cooling Holes on a Vane Endwall at Low and High Freestream Turbulence Levels | |
| type | Journal Paper | |
| journal volume | 130 | |
| journal issue | 3 | |
| journal title | Journal of Turbomachinery | |
| identifier doi | 10.1115/1.2720493 | |
| journal fristpage | 31007 | |
| identifier eissn | 1528-8900 | |
| keywords | Flow (Dynamics) | |
| keywords | Cooling | |
| keywords | Turbulence AND Coolants | |
| tree | Journal of Turbomachinery:;2008:;volume( 130 ):;issue: 003 | |
| contenttype | Fulltext |