Date of Award
Master of Science
Supersonic wind tunnels allow scientists and researchers to evaluate and analyze the behaviors of objects under real-life conditions when subjected to supersonic speeds. One of the main complexities when building a wind tunnel is the design of the convergent-divergent nozzle that is used to produce high-speed and high-quality flows. To achieve supersonic speeds, this nozzle adopts a specialized approach that incorporates the complexities of flow compressibility. The compressible effect is accurately evaluated using isentropic relations, allowing for precise determination of stagnation pressure and temperature, and static pressure and temperature relevant to the desired Mach number. Isentropic equations used to define these values, as well as the geometry of the nozzle that generates the supersonic behavior are a fundamental part of the overall design of this nozzle. The project focuses solemnly on three Mach numbers: 4.0, 5.0, and 6.0. These contours are determined by implementing the method of characteristics (MoC) assuming that the environment is under steady, axisymmetric, isentropic, and irrotational flow. The design focuses on a 2-dimensional geometry. The MoC is assumed to be used under inviscid conditions, therefore, the use of the boundary layer correction (BLC) is used to generate viscous contours after analyzing and calculating the boundary layer thickness by running Computational Fluid Dynamic (CFD) simulation using Siemens STAR-CCM+ and analyzing the Mach contour at steady state and transient conditions to visualize the flowâ??s behavior. The optimized geometries present an enhanced flow development achieving the designed Mach numbers, although the flow progression is quite unable to perfectly perform near hypersonic speeds due to the difficulties presented at these velocities, the presented Mach numbers are still achieved.
Recieved from ProQuest
Omar Antonio Dominguez
Dominguez, Omar Antonio, "An Optimization Procedure to Design Nozzle Contours for Hypersonic Wind Tunnels" (2023). Open Access Theses & Dissertations. 3965.