Numerical simulation of fluid dynamics in fluidized beds with horizontal heat exchanger tubes

A numerical code, Gemini, based on the implicit multifield method (IMF) of Harlow and Amsden for Eulerian two-fluid modelling, is used to simulate the fluid dynamics of bubbling fluidized beds, assuming no turbulence in the g as or solid phase. The paper gives a formulation of the equations of motion and empirical closure laws in general curvilinear coordinates for calculat ion of the fluid dynamics in beds with complex internal geometries. A speci al discretization method for general curvilinear structured grids with mult iblock connectivity is implemented, and two-dimensional non-stationary calc ulations are performed for a bed with a cross-sectional width of 0.3 m, con taining two horizontal heat exchanger tubes. The local visible bubble flow and the gas and particle motion around the tubes are briefly discussed and compared with experimental fluid dynamic results at different pressure leve ls. (C) 1999 Elsevier Science Ltd. All rights reserved.