Numerical Simulation of High-Speed Flow Using Computational Dynamics

Undergraduate #332
Discipline: Technology and Engineering
Subcategory: Civil/Mechanical/Manufacturing Engineering

Uthman Clark - Tuskegee University
Co-Author(s): Ovais Khan, Tuskegee University

Cavity flows are very common in everyday life. The undesirable effects of wind moving over an opening such as the cavity manifest itself as loud noise and this phenomenon is a common occurrence in many practical applications. Some of the examples include the noise experienced while driving with anopen sunroof or when the windows are rolled down, noise emanating from the wheel wells of the airplanes during landing or takeoff etc. In several other applications such as internal weapons bays and airborne platforms flying at high speed, the resulting flow results in severe vibrations due to resonance and structural failure. The proposed study will investigate the capabilities of numerical algorithms for characterizing the flow field over an open cavity exposed to high-speed flow using computational fluid dynamics (CFD). CFD utilizes the numerical techniques such as finite control volume method, finite difference method, or finite element method to approximate governing equations into forms more suitable for algorithm implementation. CFD has been commonly utilized by industrial and academic organizations to perform design and analysis of several complex aerodynamics and thermal engineering problems in the economical and efficient way.

The proposed study will encompass fundamental research in the understanding of the numerical solver to treat shock/boundary layer interaction. The development of two numerical models based on CFD approach is under progress. One model utilizes conventional numerical algorithm to simulate the supersonic and high-subsonic cavity flow field. However, the second numerical model will utilize the high-order shock capturing scheme to solve the governing fluid dynamics equations for modeling the shock/boundary layer interaction phenomenon.
Initial numerical simulations using CFD code based on fixed stencil scheme demonstrate that the computed flow field was not depicting the actual features of the flow. Expansion fan at the corner of the step does not appear and the location of oblique shock wave is not correct either. However, results obtained from the CFD model based on high-order shock capturing show appearance of an expansion fan followed by formation of an oblique shock wave at the base. A recirculation region at the corner that contains a complex structure of vortices was also formed. Work on this project is in progress and further results will be presented in the Emerging Researchers National (ERN) Conference in STEM.

References: 1. Peng, S. H., “Simulation of Turbulent Flow Past a rectangular Open Cavity Using DES and Unsteady RANS”, AIAA Paper 2006-2827, 2006.
2. Nayyar, P., Barakos, G. N., and Badcock, K. J., “Numerical Study of Transonic Cavity Flows Using Large-Eddy and DetachedEddy Simulation,” The Aeronautical Journal, 2007, pp.153

Funder Acknowledgement(s): NSF

Faculty Advisor: Ovais Khan, okhan@mytu.tuskegee.edu