The present numerical study attempts to demonstrate the moving surface riblets ef- fectiveness of altering separated-reattached transitional flows affected by adverse pressure gradient (APG). The European Research Community On Flow Turbulence and Combustion (ERCOFTAC) T3-C4 test case has been selected as benchmark for testing this dynamic wall-shaping effect. Among all the experiments performed in the well known T3 series the T3-C4 is the only one presenting a separated flow transition caused by the standing APG and a typical laminar separation bubble. The Reynolds number based on the flat plate length is 1.36 · 10^5 and this makes the usage of RANS and LES approach feasible for the numerical prediction. The k-kl-ω and k-e Launder-Sharma closure models have been used to assess the transition phenomenon with hydraulically smooth walls, firm surface riblets and riblets with a pre-determined motion. To achieve flow validation, outcomes are compared with wind-tunnel data and previously conducted numerical simulations.
Campitelli, G., Huebsch, W., Krastev, V.k. (2014). Effects of moving surface riblets on a transitional flow affected by adverse pressure gradient. In 7th AIAA Flow Control Conference. American Institute of Aeronautics and Astronautics, Inc. [10.2514/6.2014-2651].
Effects of moving surface riblets on a transitional flow affected by adverse pressure gradient
Krastev V. K.
2014-06-13
Abstract
The present numerical study attempts to demonstrate the moving surface riblets ef- fectiveness of altering separated-reattached transitional flows affected by adverse pressure gradient (APG). The European Research Community On Flow Turbulence and Combustion (ERCOFTAC) T3-C4 test case has been selected as benchmark for testing this dynamic wall-shaping effect. Among all the experiments performed in the well known T3 series the T3-C4 is the only one presenting a separated flow transition caused by the standing APG and a typical laminar separation bubble. The Reynolds number based on the flat plate length is 1.36 · 10^5 and this makes the usage of RANS and LES approach feasible for the numerical prediction. The k-kl-ω and k-e Launder-Sharma closure models have been used to assess the transition phenomenon with hydraulically smooth walls, firm surface riblets and riblets with a pre-determined motion. To achieve flow validation, outcomes are compared with wind-tunnel data and previously conducted numerical simulations.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
