NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Transition Heat Transfer Modeling Based on the Characteristics of Turbulent SpotsWhile turbulence models are being developed which show promise for simulating the transition region on a turbine blade or vane, it is believed that the best approach with the greatest potential for practical use is the use of models which incorporate the physics of turbulent spots present in the transition region. This type of modeling results in the prediction of transition region intermittency which when incorporated in turbulence models give a good to excellent prediction of the transition region heat transfer. Some models are presented which show how turbulent spot characteristics and behavior can be employed to predict the effect of pressure gradient and Mach number on the transition region. The models predict the spot formation rate which is needed, in addition to the transition onset location, in the Narasimha concentrated breakdown intermittency equation. A simplified approach is taken for modeling turbulent spot growth and interaction in the transition region which utilizes the turbulent spot variables governing transition length and spot generation rate. The models are expressed in terms of spot spreading angle, dimensionless spot velocity, dimensionless spot area, disturbance frequency and Mach number. The models are used in conjunction with a computer code to predict the effects of pressure gradient and Mach number on the transition region and compared with VKI experimental turbine data.
Document ID
19980206235
Document Type
Conference Paper
Authors
Simon, Fred (NASA Lewis Research Center Cleveland, OH United States)
Boyle, Robert (NASA Lewis Research Center Cleveland, OH United States)
Date Acquired
August 18, 2013
Publication Date
June 1, 1998
Publication Information
Publication: Minnowbrook II 1997 Workshop on Boundary Layer Transition in Turbomachines
Subject Category
Fluid Mechanics and Heat Transfer
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

Related Records

IDRelationTitle19980206205Analytic PrimaryMinnowbrook II 1997 Workshop on Boundary Layer Transition in Turbomachines
Document Inquiry