OCR Text |
Show 20 Jordan Loftus SeD. Texaco Inc - August 24. 1989 is computed on the flue gas partial pressures of carbon dioxide and water and the path length based on the first tube section. User may elect to add a soot extinction coefficient. There are very large number of correlations in the literature for heat transfer to and pressure drop across tube banks: For bare tubes the heat transfer as given in perr~/s2l and pressure drop as proposed by Gunter and Shaw 2 is used, For annular circular fin of uniform thickness a closed Bessel formed solution23 has been derived for a single fin. The assumption made is that the exchange between fin and fluid is by a uniform heat transfer coefficient. For multiple fins, the assumption becomes poorer as the number of fins per inch increases. For annular circular fin, either solid or segmental, an empirical method by ESCOA24 is used. The computer output prints a row by row analysis of the duty as well as the process, and flue gas temperatures and draft profile. For rows having fins, the tip temperature is printed and oxidation limit flagged. IX. RP530PGH - Tube Heta11urgy and Thickness Routines RP530PGH is based on API-RP530 "API Recommended Practices for Calculation of Heater Tube Thickness in Petroleum Refineries". The physical properties for the tube materials (including stress - temperature data) cited in RP530 are stored in the program. User may elect to provide the program data for materials not in RP530. 21. Chemical Engineering Handbook, 4th Ed. Eq 10-42 22. Gunter, A Y and Shaw, W A, "A general correlation of friction factor for various types of surfaces in cross flow", Trans. ASHE 67 (1945) 643 23. Gardner, K A,"Efficiency of Extended Surface" Trans ASHE, Nov 1945, 621-631. 24. Weierman C., "Ease the Selection of Finned Tubes", ESCOA Fintube Corp., Oil & Gas Journal, Sept 6 1976, Vol.74, No.36 and Weierman C., "Fintubes Can Lower Heat Transfer Cost", ESCOA Fintube Corp., Oil & Gas Journal, Nov 3 1975, Vol.73, No.44 |