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This paper presents the first part of a 3D numerical simulation of a horizontal-bed open-channel water flow with a 90° equal-width junction. A commercially available CFD package is used. The results of the numerical simulations are compared with the experimental data published by previous researchers. The numerical simulation was carried out in two steps: (a) using a Cartesian mesh to determine the shape of the free surface, and (b) using a body-fitted mesh conforming to the free-surface shape. The first step yielded a fair comparison between simulated and experimentally determined free-surface profiles. Further work on the simulation in the second step is continuing. This study is also the first stage of a project involving numerical modeling of open channel junction flows with suspended sediment transport.

This paper describes work in the first part of an ongoing research programme on the generation and dispersion of fume from ' hot metal processes, a challenging industrial ventilation problem. '"This phase of the study involves research into a salt solution plume generated from an area source and descending into quiescent water. This is a 'cold flow' analogue of a thermal lume ascending in quiescent air. Expenments are described whereby the velocity and concentration profiles in the plume are determined using video footage and particle-tracking software, and a conductivity probe with digital traversing mechanism, respectively. Results from a transient numerical simulation of the flow using the CFD package PHOENICS are generated and compared with experimental results. These are also used to characterise the plume with respect to density and velocity distributions.

This paper describes work in the first part of an ongoing research programme on the generation and dispersion of fume from hot metal processes, a challenging industrial ventilation problem. This phase of the study involves research into a salt solution plume generated from an area source and descending into quiescent water. This is a 'cold flow' analogue of a thermal plume ascending in quiescent air. Experiments are described whereby the velocity and concentration profiles in the plume are determined using video footage and particle-tracking software, and a conductivity probe with digital traversing mechanism, respectively. Results from a transient numerical simulation of the flow using the CFD package PHOENICS are generated and compared with experimental results.

Analytical and experimental investigations exploring a new, potentially useful idea for a type of particle injector are presented. The injector is designed to work on the principles of gas dynamics, and can be used for transporting dry particulate matter to high pressure destinations and processes. The proposed device is expected to overcome many of the limitations (such as limited operating/back pressure, moving parts, clogging, deterioration due to particle agglomeration) of conventionally used particle feeders. The basic idea involves creation of a zone of relatively low pressure in a supersonic gas stream in a duct, and introducing the particulate matter into this zone. The particulate matter is then conveyed by the gas stream to the high pressure destination through a normal shock. The aim, motivation and basic concepts of the project are introduced in Chapter 1. The relevant available literature is also surveyed. Chapter 2 contains an overview of the project. The technique used for the analytical investigation of the flow in the proposed injector is introduced. Chapter 3 contains an analytical investigation of flow in the Injection Tube. Chapter 4 presents an analysis of the primary gas flow, which leads to nozzle design. Flow in the Interaction Region is investigated in Chapter 5. Chapter 6 introduces a 'Modified-Fanno' model for the pseudo-shock, developed during the course of the analytical investigation of flow in the Compression Region. In Chapter 7, the 'Modified-Fanno' model is extended to suspension flows. Chapters 8 and 9 contain two-dimensional and three-dimensional PHOENICS simulations of the flow in the injector duct, respectively. Chapter 10 contains an account of design considerations and fabrication details of the experimental facility and a description of the flow visualisation technique. Chapter 11 presents results of the experimental investigation, along with comparisons with theoretical predictions. Chapter 12 presents conclusions and recomm