The Influence of Incoming Boundary Layer on the Flow around the Surface Excrescence

Abstract:

This paper is concerned with the accurate prediction of parasitic drag due to excrescences introduced by structural repairs to aircraft wings and fuselage. Numerical computations are carried out to quantify the effect of isolated surface excrescences in a turbulent boundary layer on a flat plate. Both step excrescence in 2-D domain and wall-mounted hexahedron in 3-D domain are considered in the investigation. Various approaches for calculating drag coefficient increments for wing repair plates are presented. Menter's Shear Stress Transport (SST k-ω) turbulence model is employed here for its accurate prediction of aeronautics flows at typical repair locations with strong adverse pressure gradients and separation. Solutions are obtained via a high-order numerical scheme and an implicit time-marching approach on a multi-block structured mesh. A grid resolution study was carried out to confirm the accuracy of the computations. From the results curves are drawn showing the variation of parasitic drag components for a range of controlled speed (Mach 0.1 to 0.8), local Reynolds number (10⁴ to 10⁷) and the height of excrescence (y⁺=10² to 10⁴).

• Periodical: Applied Mechanics and Materials (Volume 846)
• Pages: 48-53
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.846.48
• Online since: July 2016
• Authors: Yao Zu Bi*, Ben Thornber
• Keywords: Boundary Layer, k-ω-SST, Parasitic Drag, Repair Plate

References

[1] M. Hahn, S. Lawson, A.J. Peace, A. Miller and T. Chant, Assessment of methods for the prediction of parasitic drag due to wing repairs, in 30th AIAA Applied Aerodynamics Conference, p.2891, (2012).

DOI: 10.2514/6.2012-2891

[2] J. Labroquere, R. Duvigneau, and E. Guilmineau, Impact of turbulence closures and numerical errors for the optimization of flow control devices, in 21th AIAA Computational Fluid Dynamics Conference, San Diego, USA, (2013).

DOI: 10.2514/6.2013-2846

[3] D. Driver, and H. Seegmiller, Features of a reattaching turbulent shear layer in divergent channel flow. AIAA journal, Vol. 23, No. 2, 1985, p.163–171.

DOI: 10.2514/3.8890

[4] Menter, F. R., Two-Equation Eddy-Viscosity Turbulence Models for Engineering Applications, AIAA Journal, Vol. 32, No. 8, August 1994, pp.1598-1605.

DOI: 10.2514/3.12149

[5] C. Rumsey, Turbulence Modeling Resource, Langley Research Centre, information on http: /turbmodels. larc. nasa. gov/flatplate_sst. html, Last Updated: 08/06/(2015).

[6] M. Ariff, S. M. Salim, & S. C. Cheah, Wall y+ approach for dealing with turbulent flows over a surface mounted cube: part 2 - high Reynolds number, in: Proceedings of Seventh International Conference on CFD in the Minerals and Process Industries, Melbourne, Australia, (2009).

DOI: 10.1504/pcfd.2010.035368

[7] NASA, 2D Zero Pressure Gradient Flat Plate Validation Case, Turbulence Modeling Resource Langley Research Center, (2014).

[8] A. Yakhot, T. Anor, H. Liu and N. Nikitin, Direct numerical simulation of turbulent flow around a wall-mounted cube: spatio-temporal evolution of large-scale vortices. J. Fluid Mech., (2006).

DOI: 10.1017/s0022112006002151

[9] Martinuzzi, R., Tropea, C., 1993. The flow around surface-mounted, prismatic obstacles placed in a fully developed channel flow. Trans. ASME, J. Fluid Eng. 115 (1), 85–91.

DOI: 10.1115/1.2910118