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A simulation study of the BERL Combustor 1, 2, using Computational Fluid Dynamics (CFD), is presented. This work is part of John Zink Company’s effort to validate the CFD models most frequently used by the Simulation Technology. Solutions group to provide modelling services for its customers and to support internal R&D. The CFD results are carefully compared with the experimental data from the BERL project. The current study focused mainly on combustion models and turbulence models. To simulate combustion processes, the selection of an applicable combustion model is a key decision a CFD engineer has to make. The PDF model, multiple flamelets model, eddy dissipation model, and finite-rate/eddy-dissipation model with two different global rates were tested. Simulation results show that the finite-rate/eddy-dissipation model provided the closest agreement with the BERL data. The standard k-ε, realizable k-ε, RNG k-ε, and Reynolds Stress turbulence models were evaluated as the closures. The simulation study indicates that all the turbulence models yielded good agreement with measurements in the highly reacting zone. However, the accuracy of these models varied in areas away from the reacting zone. In some cases, the discrepancy between the predictions and measurements was as high as 20% at certain locations. Finally, discussions and future work are provided.

A double fired process heater with combination oil/gas burners has been modeled with computational fluid dynamics (CFD). The process heater was simulated with two configurations: 1) with internal walls, and 2) without internal walls. The purpose of this study is to understand the effect of the internal walls on flame shape and process tube heat flux. As a result of removing the internal wall, furnace currents are allowed to have a large influence on the flame patterns and the flames lean toward the tubes. It is also shown that higher localized heat fluxes occur on the process tubes with the walls removed. This study demonstrates that the primary function of the internal walls is to isolate cells within the furnace which create satisfactory process tube heat fluxes.

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