Experiments and Computations of Localized Pressure Gradients with Different History Effects
2014 (English)In: AIAA Journal, ISSN 0001-1452, E-ISSN 1533-385X, Vol. 52, no 2, 368-384 p.Article in journal (Refereed) Published
The study of high-Reynolds-number wall-bounded turbulent flows has become a very active area of research in the past decade, where several recent results have challenged current understanding. In this study, four different localized pressure gradient configurations are characterized by computing them using four Reynolds-averaged Navier-Stokes turbulence models (Spalart-Allmaras, k-epsilon, shear stress transport, and the Reynolds stress model) and comparing their predictions with experimental measurements of mean flow quantities and wall shear stress. The pressure gradients were imposed on high-Reynolds-number, two-dimensional turbulent boundary layers developing on a flat plate by changing the ceiling geometry of the test section. The computations showed that the shear stress transport model produced the best agreement with the experiments. It was found that what is called "numerical transition" (a procedure by which the laminar boundary conditions are transformed into inflow conditions to characterize the initial turbulent profile) causes the major differences between the various models, thereby highlighting the need for models representative of true transition in computational codes. Also, both experiments and computations confirm the nonuniversality of the von Karman coefficient kappa. Finally, a procedure is demonstrated for simpler two-dimensional computations that can be representative of flows with some mild three-dimensional geometries.
Place, publisher, year, edition, pages
2014. Vol. 52, no 2, 368-384 p.
Turbulent-Boundary-Layers, Moderate Reynolds-Numbers, Large-Scale, Pipe-Flow, Models, Transition, Simulation, Region
Engineering and Technology
IdentifiersURN: urn:nbn:se:kth:diva-148274DOI: 10.2514/1.J052516ISI: 000337804700012ScopusID: 2-s2.0-84894248925OAI: oai:DiVA.org:kth-148274DiVA: diva2:736035
QC 201408042014-08-042014-08-042014-08-04Bibliographically approved