A hybrid method for simulation of axial ̄ow impeller driven mixing vessels
نویسندگان
چکیده
A hybrid method for the simulation of Reynolds-averaged turbulent ̄ows in axial ̄ow impeller driven mixing vessels is described. The time-mean ̄ow in the impeller region is modelled using blade element theory, while the ̄ow in the remainder of the vessel is simulated using a second-order ®nite-volume Reynolds-averaged numerical scheme. The two models are iteratively coupled through boundary conditions and computation of the power dissipated in the mixing vessel. This approach is computationally cheaper than alternatives that require the details of the ̄ow in the impeller region to be resolved. Simulation results are compared to a detailed laser-Doppler examination of the ̄ow in a laboratory vessel, and it is shown that the average absolute dierence between simulated and measured velocities was of the order of 1% of the impeller tip speed. In addition the power consumption was predicted to two-®gure accuracy. Ó 2000 Elsevier Science Inc. All rights reserved.
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