Engineering Commons^™

Non-Circular Hydraulic Jumps Due To Inclined Jets, Ahmed Mohamed Abdelaziz

Electronic Thesis and Dissertation Repository

When a laminar inclined circular jet impinges on a horizontal surface, it forms a non-circular hydraulic jump governed by a non-axisymmetric flow. In this thesis, we use the boundary-layer and thin-film approaches in the three dimensions to theoretically analyse such flow and the hydraulic jumps produced in such cases. We particularly explore the interplay among inertia, gravity, and the effective inclination angle on the non-axisymmetric flow.

The boundary-layer height is found to show an azimuthal dependence at strong gravity level only; however, the thin film thickness as well as the hydraulic jump profile showed a strong non-axisymmetric behaviour at all …

Numerical Simulation And Scaling Of Thunderstorm Downburst Outflows, Cristiano Andre Rodrigues Kondo

Electronic Thesis and Dissertation Repository

A downburst is a natural phenomenon that occurs during thunderstorms, creating hazards and damage to infrastructure due to the strong winds produced. This research contributes to the current literature by applying the Lundgren et al. scaling parameters (R₀, T₀, V₀) to scale cooling source (CS) downburst simulations. The research also investigates the effects of the environmental lapse rate (ELR) on full-scale downburst outflows and compares the full-cloud model with the subcloud model simulations. The results showed that the scaling parameters preserve the temporal and vertical radial wind speed profile shape, as well as the …

Integrated Modelling Of Wastewater Treatment And Sewer Processes - Interactions Of Fluid Flow, Mass Transfer, And Biochemical Reactions, Ahmed Khalil

Electronic Thesis and Dissertation Repository

Numerical modelling of wastewater management systems is crucial for investigating alternative designs and developing strategies for operation and control that improve the performance of the treatment stage (such as improving the aeration systems in activated sludge systems). Modelling can also help operators to mitigate common problems that arise from unwanted biochemical conversions in the sewer networks (such as the production of sulfide and methane). Therefore, this work focuses on two major areas related to modelling wastewater management systems. First, it seeks to develop more accurate models for aeration systems in activated sludge reactors. Second, it seeks to study the mathematical …

Experimental Simulation Of A Density-Driven Downburst Translating Within A Turbulent Boundary Layer, Shivani Ashitkumar Jariwala

Electronic Thesis and Dissertation Repository

Downburst outflows emerging from thunderstorm producing clouds are contained within the atmosphere where the outflow interacts with the preexisting atmospheric boundary layer (ABL). This novel study employs a realistic approach for experimental simulation of downbursts by translating the downburst source within a scaled ABL within a hydraulic flume system that produces open channel flow. The density-driven model approach is used, involving an iris operated cylinder release mechanism translating inside the ABL generated over a restrictive fetch using passive turbulence generating devices at model scales of 1:5500 and 1:10,000. The velocity vector fields across a vertical plane revealed asymmetrical outflows generated …