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Show 12 Jordan Loftus SeD. Texaco Inc - August 24. 1989 where ~X, ~Y, ~z are the edges of the gas volume zone and N is an integer. Each zone is then divided into subzones by dividing X, Y and Z dimensions by the integer of ~X/B etc. The direct interchange areas (DIA) of each subzone are computed by the Hottel and Cohen correlations 14 . The zone DIA is then calculated by the double summation of the subzones DIA's. 2. Compute the leaving flux density by inverting the Hottel and Sarofim's matrix 11-2. 3. Compute the TIAs by Hottel and Sarofim's equations 11-5, 6 and 7. Verify fit by their equations 8 & 9. C. Flow Field Generation A simplified similarity of jet theory algorithm is used to compute the three dimensional flow field. There are 3 axial regions in the jet Z direction and a fourth to account for exit locations as well as flue gases ow entering the gas space from previously computed gas space(s). These regions are referred to as: 1. Conservation of Momentum 2. Dissipation of Momentum 3. Plug Flow 4. Dissipation Flow The mesh size is refined to 6 by 8 by 8 subzones per gas volume. Each burner is assigned a portion of its XY boundary surface zone. The first three regions are depicted in Figure lOa and the fourth for flue gas flow from an adjacent gas space, in Figure lOb. 1. Conservation of Momentum When a fluid issues from a opening into a quiescent fluid a jet flow pattern is set up. This pattern is characterized by a forward flow within a central conical section and an aspirated fluid from the surroundings. Within the jet, the flow is Gaussian: uz,r - uz,o EXP [ - K (r/z)2j Eq. 11._ where u is the axial velocity, r is the radial distance at z, and z is the distance from jet origin, K is the flow constant. 14. · Hottel, H.C. and E.S. Cohen: AIChE J, 4:3 (1958). |