Flow distribution in four possible configurations, CP-z, CP-π, CF-z, and CF-π, of a radial flow reactor is investigated using computational fluid dynamics (CFD). The CFD models are validated using published experimental data. It is found that one of the π-flow configurations always has the most uniform flow distribution. Results show that the ratio of the center pipe cross-sectional area to that of the annular channel has a significant effect on the flow distribution. For a ratio less than one, the CF-π configuration gives the most uniform flow, while the CP-π is preferred for a ratio larger than one. It was also shown that the uniformity of the flow distribution is enhanced by lowering the porosity of the center pipe and that of the bed. To ensure good distribution, partial blockage of the center pipe must be avoided.

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The campaign life of a blast furnace is limited by the erosion of hearth refractories. Flow and temperature distributions of the liquid iron have a significant influence on the erosion mechanism. In this work, an improved three-dimensional computational fluid dynamics model is developed to simulate the flow and heat transfer phenomena in the hearth of BlueScope's Port Kembla No. 5 Blast Furnace. Model improvements feature more justified input parameters in turbulence modeling, buoyancy modeling, wall boundary conditions, material properties, and modeling of the solidification of iron. The model is validated by comparing the calculated temperatures with the thermocouple data available, where agreements are established within ±3 pct. The flow distribution in the hearth is discussed for intact and eroded hearth profiles, for sitting and floating coke bed states. It is shown that natural convection affects the flow in several ways: for example, the formation of (a) stagnant zones preventing hearth bottom from eroding or (b) the downward jetting of molten liquid promoting side wall erosion, or (c) at times, a vortex-like peripheral flow, promoting the ''elephant foot'' type erosion. A significant influence of coke bed permeability on the macroscopic flow pattern and the refractory temperature is observed.

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Numerical and experimental investigations of mixing in pipelines with side and opposed tees are carried out. Cold water flowing in a main pipe is mixed with hot water flowing through a tee. The temperature is measured experimentally to quantify the degree of mixing. The velocity and temperature fields are also solved numerically. The effects of the mesh size, mesh-localized refinement, dependence of the fluid physical properties on temperature, and turbulence model on numerical results were examined. Experimental results show good agreement with corresponding predictions of the numerical model over a relatively wide range of Reynolds number; however, close agreement is harder to obtain in the vicinity of the jet through the tee. The pipe length required to achieve 95% mixing is found to be a function of U j/U m. The angle at which the side jet is injected determines whether the jet impinges on the opposite wall and also affects the pipe length required to achieve 95% mixing. This work recommends that industry should not use 90° tees because of possible poor mixing at certain velocity ratios and hard impingement. For pipe diameters ranging from 1 to 16 in., if d j/d m is kept constant, then for any velocity ratio the 95% mixing is achieved at a distance corresponding to about the same number of the main-pipe diameters. For opposed jets, numerical convergence was harder to obtain at high Reynolds numbers. Some modifications, including the staggering of the two jets, made it easier for the solution to converge.