Showing papers by "Ralph L. Webb published in 1985"

An Analytical Model to Predict Condensate Retention on Horizontal Integral-Fin Tubes

Abstract: Construction d'un modele analytique general pour la prevision de la surface inondee au cours de la condensation sur tube a ailette horizontal. Comparaison des resultats du modele avec des donnees experimentales pour des tubes avec un nombre d'ailettes variable entre 748 et 1378 par metre

Prediction of the Condensation Coefficient on Horizontal Integral-Fin Tubes

Abstract: Construction d'un modele theorique pour la prevision des coefficients de condensation sur des tubes a ailettes pour des fluides a tension superficielle elevee et faible. Utilisation du modele au calcul du coefficient de condensation du freon 11 sur des tubes a ailettes horizontaux avec 748, 1024 et 1378 ailettes/metre. Comparaison avec des donnees experimentales

Performance Simulation of Evaporative Heat Exchangers [Cooling Towers, Fluid Coolers, and Condensers]

Abstract: This paper presents a description of three computer algorithms developed to perform rating calculations of commercially available cooling towers, evaporative fluid coolers, and evaporative condensers. The paper illustrates the various simulations that are possible, including varying wet-bulb, inlet and exit temperatures, different fluid flow rates, altitude, or combinations of the above. The heat and mass transfer “characteristic equations, ”as a function of the fluid flow rates for a given evaporative heat exchanger, are derived from the manufacturer's rating data on one operating point, e.g., at the rating point. Or, one may use independently developed “characteristic equations” for any packing or tube bundle geometry of interest. The algorithms provide capability to predict the heat exchange capacity at any weather or process condition. They also allow the plant engineer to assess the effect of varying the air flow rate on the fan power for specified operating conditions. Example cases are ana...