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Show 4 Jordan Loftus SeD. Texaco Inc - August 24. 1989 there are wide range of coil layouts possible in the radiant section. In the simplest case there is a single radiant gas space and the tubes are located adjacent to side walls with burners located either at the end walls or in the floor. In more complex arrangements of the firebox, there may be multi-gas spaces each with own set of burners, tubes may be located adjacent to the floor, roof, end walls as well as the side walls and burners may be located on any wall. III. Heater Design System (HDS) Development In 1939 Lobo and Evans 6 demonstrated that a single wellstirred gas zone model was a 'land mark' improvement over previous empirical methods. The main disadvantage is its inability to differentiate the heat flux to the process coil. The single well-stirred gas zone model would not be suitable to predict the maximum tube wall temperatures for cells 1 and 2 in Figure 4. Hoogendorn etal 7 measured a 3.5/1 peak to average flux in an experimental furnace. All radiative aspects of the HDS algorithm is based on the work of Professor Hoyt C. Hottel and co-workers B. The flow field model is based on axial burner recirculation for confined jet influenced by the work of the International Flame Research Foundation 9 . In 1967 Dr. J Loftus lO collaborated wieh Prof. A. F. Sarofim and Dr. H. C. Schutt to develop a pluf flow - 7 Hottel zoning of an Ethylene furnace. In 1971 Loftus l extended the model to 6. Lobo, W. E. and Evans, J. W. "heat Transfer in Radiant Section of Petroleum Heaters", Trans AIChE 35 (1939) 743-748. 7 Hoogendorn, C.J. etal, Koningklie/Shell Laboratorium, Amsterdam, "Heat Flux Studies in Vertical Furnaces", J. Inst. Fuel (Dec 70), 522-6. 8. Hottel, H.C. and A.F. Sarofim, "Radiative Transfer", ncGraw-Hill (1967). 9. Beer, J.n. and N. A. Chigier, "Combustion Aerodynamics" Halstead Press Div., John Wiley (1972), Section 2.7 Confined Jets . 10. Loftus, J., A. F. Sarofim and H. C. Schutt, "Design of Furnaces for Tubular Reactors", Chemical Engineer Progress 63 (July 67) 47-54. 11. Loftus, J. "Development and Design of Reactor Furnaces" , NPRA Computer Conference, Houston, Nov. 3, 1971. |