A Study on Hydrodynamics in Fixed Bed with Cross Flow

The pressure distribution of the fixed-bed embedded a crossed tube or two tubes was measured and the velocity distribution and stream function were got according to the two-dimensional mathematical model simulation. It indicates that the zone of the velocity field affected by tube is near the wall of the tube. For the case of one crossed tube embedded, the velocity component u, along the main gas flow direction, increases remarkably in the range of twice tube diameter in y direction and this effect reaches to the bed boundary. Maximum of u is 1.5 times the bulk gas velocity. Before and after the tube, u descends to 40% of the bulk gas velocity because of the tube hindrance. The distance that velocity u affected by tube is 1.5 times tube diameter in x direction. Far from the tube, the velocity component v, vertical to the main gas flow direction, is zero. Its maximum appears at the close tube wall and is 50% of the bulk gas velocity. The distance that velocity component v affected by the tube is 1.5 times diameter in x direction while it is about twice diameter in y direction. The bigger Reynolds number, the deeper the tube effect on velocity. For the case of two tubes embedded, the velocity component u descends before and after two tubes and increases between two tubes. The curve peak and width have relation to the space between two tubes, distance to tubes center and Reynolds number.