Physics 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 …

Cfd Simulations Of Bubble Column Equipped With Bundles Of Concentric Tubes, Glen C. Dsouza

Electronic Thesis and Dissertation Repository

Bubble column reactors are multiphase contactors that have found several industrial applications owing to various attractive features including excellent thermal management, low maintenance cost due to simple construction and absence of moving parts. In order to attain desired performance for a given application, these reactors are usually equipped with internals such as vertical tube bundles to facilitate heat transfer. The column hydrodynamics and turbulence parameters are altered when the column is occluded with internals which adds to the complexity of the problem. The use of Computational Fluid Dynamics (CFD) tools for the study of multiphase flows has gained a lot …

Development Of Ultrasonic Techniques For Characterization Of Liquid Mixtures, William A. Cooke

Electronic Thesis and Dissertation Repository

To evaluate the suitability of ultrasonic techniques for on-line process monitoring applications, an ultrasonic probe was used to measure acoustic velocity, acoustic impedance, and isentropic compressibility of hydrocarbons (including n-, iso-, and cycloalkanes, toluene, mineral oil, and crude oil) and polar liquids (alcohols, water, salt water) over a temperature range of 25-60°C. Temperature, carbon chain length, molecular shape, and intermolecular forces had significant effects on ultrasonic parameters. Relationships between media characteristics and observed ultrasonic parameters were modeled using empirical-least squares equations. The same parameters were measured in binary mixtures of hydrocarbons in heptane, as well as polar liquids in ethanol. …

Plasmonic Optical Sensors: Performance Analysis And Engineering Towards Biosensing, Peipei Jia

Electronic Thesis and Dissertation Repository

Surface plasmon resonance (SPR) sensing for quantitative analysis of chemical reactions and biological interactions has become one of the most promising applications of plasmonics. This thesis focuses on performance analysis for plasmonic sensors and implementation of plamonic optical sensors with novel nanofabrication techniques.

A universal performance analysis model is established for general two-dimensional plasmonic sensors. This model is based on the fundamental facts of surface plasmon theory. The sensitivity only depends on excitation light wavelength as well as dielectric properties of metal and dielectrics. The expression involves no structure-specified parameters, which validates this formula in broad cases of periodic, quasiperiodic …