An Improved Model for Liquid-Side Fouling Thermal Resistance in Enhanced Tubes

Sticking probability and deposit bond strength were considered to be constant in the previous fouling prediction models, which turned out to be problematic in the latest study. A theoretical model of fouling in internal helical-rib tubes, which is more theoretically reasonable, was developed in this paper based on the long-term fouling data reported by Li and Webb, targeting to improve previous fouling models. Compared with previous models, the results show that the new model has both a direct physical significance and a higher accuracy with a maximum deviation of 5.20% and an average deviation of 1.87%. In order to ensure precision, the previous models can only predict the segmentation function with p/e around 3.5. While the new method presented in this paper, with simple formulas and clear physical meanings, provides a better modeling method for the follow-up study in the field of thermal resistance of enhanced fouling tubes.