One-equation transition closure for eddy-viscosity turbulence models in CFD

A method is presented to reduce the order of the Langtry-Menter transition model by replacing the transport equation containing the transition criterion with a locally-defined algebraic correlation. The new method has the same applicability and generality as the original form of the model, and test cases run in OVERFLOW for the S809 and E387 airfoils show that comparable accuracy is achieved. The primary validation cases use the two-equation SST model as the underlying turbulence model, as this was used in the original model. A method is presented for using the Spalart-Allmaras turbulence model with the transition closure models, but the results were found to be very dependent on free-stream conditions. The overall applicability of the transition models to one-equation turbulence models is discussed, and goals for future development are listed.