Master of Science
Computational fluid dynamics simulations are conducted to study jet flows emanating from a circular cross-sectioned orifice. Fluid is injected on a jet into a cuboid domain containing the same fluid at a quiescent state initially. Simulations are performed for a range of Reynolds number from 1050 to 2700 at various instant illustrating the secondary flows induced by well know Kelvin Helmholtz instabilities. Large eddy simulations utilizing Smagorinsky-Lilly turbulence model are performed to characterize the spatial and temporal nature of flow field. snappyHexMesh utility is used to discretize the computational domain and pimpleFoam solver is used to solve the equations governing the fluid motions. The evolution of velocity and vorticity field is presented on flow images for various values of Reynolds number. It is demonstrated that the nature of secondary flows is strongly dependent on Reynolds number. It is also demonstrated that the evolution and spatial characteristics of secondary flows is strongly dependent on the level of disturbance introduced at the inlet. Our predicted results for the flow field degree agree well with results of experimental observations documented in the literatures validating the mathematical model and the numerical method employed. This study aids in designing and optimizing combustion chambers or designing nozzles including jets emanating from orifices.
Xue, Guanyang, "Computational Study of Jet Flows Emanating from a Circular Orifice" (2017). Theses and Dissertations. 2892.