Date: Tuesday, May 14, 2013

Time:11:00am-noon (EST),

Location: NIA room 101

Speaker: Benjamin Duda

Biography: Dr. Benjamin Duda started a post-doctoral fellowship at NASA Langley Research Center, working on hybrid RANS/LES turbulence modeling. He received his Ph.D. in fluid dynamics from ISAE Toulouse, where he was working on scale-resolving simulations for jets in cross flow. The work for this industry-sponsored doctoral research study was carried out at Airbus and Ansys and supervised by ONERA.

Abstract: Numerical methods for the simulation of hot jets in cross flow at high Reynolds numbers and small momentum ratios are presented. Different turbulence modeling strategies, i.e. URANS, SAS, DDES and ELES, are validated against experimental data on a generic configuration, highlighting the necessity of scale-resolution for a correct prediction of thermal mixing. The analysis of transient flow simulations allows the identification of inherent flow dynamics as well as mixing phenomena and the application of the Proper Orthogonal Decomposition revealed the lateral wake meandering as being one of them. Due to the multi-scale problem which arises when simulating jets in cross flow on real aircraft configurations, the sequential approach based on the SAS turbulence model is introduced. As results for the exhaust of a nacelle anti-icing system comprising multiple jets in cross flow agree well with flight test data, the approach is applied in a last step to the complex exhaust of a pre-cooling system, emphasizing the capabilities of this methodology in an industrial environment.