Master of Science (MS)
Mechanical and Aerospace Engineering
cfd, compression corner, expansion corner, expansion wave, oblique shock, viscous flow
Oblique shocks and expansion waves are commonly found in aerospace applications such as wings and nozzles. These types of shocks change the properties of the flow, thus causing changes in the lift, drag, and/or heat transfer. Hypersonic flow is important to study as its impacts are significant. In this thesis, computational fluid dynamics (CFD) is utilized to characterize the physics of the flow. Parametric studies of the Mach number and turning angle were conducted. Simulations included both inviscid and viscous flows to demonstrate the effects of boundary layer on flow properties. The majority of the viscous flows were focused on the compression corner where the boundary layer started growing. The simulations produced evidence of flow separation at high turning angles. In addition, the boundary layer turned the flow upward at an angle, causing an oblique shock before reaching the corner. This phenomenon is known as shock-shock interaction. A turbulent flow developed a boundary layer faster than a laminar flow and can delay the separation of the flow. In general, the boundary layer can offset the properties of the flow, and a part of this study was performed to obtain the percentage difference and then use it as the correction factor for the offset.
Ngo, Freddy, "Numerical Investigation of Fundamental Physics for Flows over Expansion and Compression Corners" (2011). Master's Theses. 4066.