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Rotational effects on impingement coolingThe present consideration of rotation effects on heat transfer in a radially exhausted, impingement-cooled turbine blade model gives attention to experimental results for Reynolds and Rossby numbers and blade/coolant temperature ratio values that are representative of small gas turbine engines. On the basis of a model that encompasses the effects of Coriolis force and buoyancy on heat transfer, bouyancy is identified as the cause of an average Nusselt number that is 20-30 percent lower than expected from previous nonrotating data. A heuristic model is proposed which predicts that the impingement jets nearest the blade roots should deflect inward, due to a centripetal force generated by their tangential velocity counter to the blade motion. Potentially serious thermal stresses must be anticipated from rotation effects in the course of blade design.
Document ID
19870058564
Document Type
Conference Paper
Authors
Epstein, A. H. (Massachusetts Inst. of Tech. Cambridge, MA, United States)
Kerrebrock, J. L. (Massachusetts Inst. of Tech. Cambridge, MA, United States)
Koo, J. J. (Massachusetts Inst. of Tech. Cambridge, MA, United States)
Preiser, U. Z. (MIT Cambridge, MA, United States)
Date Acquired
August 13, 2013
Publication Date
January 1, 1987
Subject Category
FLUID MECHANICS AND HEAT TRANSFER
Funding Number(s)
CONTRACT_GRANT: NAG3-335
Distribution Limits
Public
Copyright
Other