Graduation Semester and Year
Fall 2024
Language
English
Document Type
Thesis
Degree Name
Master of Science in Aerospace Engineering
Department
Mechanical and Aerospace Engineering
First Advisor
Vijay Gopal
Abstract
High-speed wind tunnels are essential facilities for conducting research and testing in external and internal flows. This thesis details the design and development of a blow-down supersonic free-jet facility with a 3-inch square nozzle in the Mach number range of and unit Reynolds number ranging. Key aspects of the facility development include the detailed design of the gas supply system, control valve selection, plenum, nozzle, test section, and the selection of an exhaust silencer. CAD designs for all the components of the facility were also generated in this effort.
A new analytical approach was developed to design supersonic contoured nozzles for wind tunnel applications. In the proposed nozzle design method, a streamline is selected as the desired contoured nozzle wall inside a reference nozzle, which is a simple, inviscid, sharp-cornered minimum-length nozzle generated using Method of Characteristics (MoC). Several streamlines are generated within the reference nozzle, and specific criteria based on the centripetal acceleration of the gas and the curvature of the sonic line for selecting a streamline as the contoured nozzle wall are discussed. The selected streamline is then corrected for viscous effects using integral boundary layer analysis. This approach simplifies the complexities of the conventional supersonic contoured nozzle design method proposed by J.C. Sivells. A comparative numerical study of the nozzle exit profiles generated by the conventional approach and the new streamline-based approach is carried out using ANSYS-Fluent. For numerical study, the model using a pressure-based solver is considered. Both nozzle design approaches generated flow conditions that are in good agreement with the targeted flow properties at . However, the streamline nozzle design method slightly outperformed the Sivells method in terms of quantifiable performance parameters, such as core flow area size, flow distortion, and flow angularity.
Finally, the expansion of the free-jet test rhombus to a constant-area test section is discussed. The pressure gradient developed in the constant-area test section due to Fanno flow and the total pressure at which shock-train enters the test section during sub-atmospheric operations is of interest. These parameters were studied using sub-scale experiments in a smaller free jet. The results were scaled up using non-dimensional parameters for the designed 3-in square free-jet facility to better understand the flow conditions in the test section and the operational envelope of the facility.
Keywords
Supersonic, wind tunnel, Free jet, Nozzle design, Streamline tracing, test section
Disciplines
Aerodynamics and Fluid Mechanics | Propulsion and Power
License
This work is licensed under a Creative Commons Attribution 4.0 International License.
Recommended Citation
Somaroutu, Gowtham Sai, "Design and Development of Supersonic Free Jet Facility" (2024). Mechanical and Aerospace Engineering Theses. 1027.
https://mavmatrix.uta.edu/mechaerospace_theses/1027