Flow Resistance and Energy Analysis of Urban Sewage Delivery Heat Transfer System

The thimble delivery heat-transfer (TDHT) system is one of the primary modes to utilize the energy of urban sewage. Given out the Schematic diagram of TDHT system, introduced the definition of equivalent fouling roughness height, used the Niklaus semi-rational resistance coefficient formula in rough region, the calculation methods of the sewage flow resistance are explained. Through the resistance contrastive analysis of sewage and pure mediate water, the results indicate that the mediate water sub-system is the primary design point of TDHT system. The economical ratio of flux and velocity are determined by optimization analysis of investment and operating cost in the technical feasible range. The thesis will provide reference for pipe design and pump selection of urban sewage cool or heat source applied delivery heat transfer method.