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Based on the Turian–Yuan heterogeneous resistance model, the simulation results of three urban sludge pipelines with a volumetric concentration of 2.38, 3.94, and 5.39% were analyzed. The reasons for the large deviation of the simulation results under high Reynolds number conditions were also analyzed. The results showed that the deviation of the simulation was mainly caused by the difference between the sludge volumetric concentration ( C V ), the settlement resistance coefficient ( C D ), and the values of the two parameters in the Turian–Yuan heterogeneous resistance model. Consequently, it was necessary to optimize the index m 1 of C V and the index m 2 of C D . Taking mean square deviation as the objective function, using Matlab programming, the abovementioned two indexes were optimized by the simulated annealing algorithm. The optimized index m 1 of C V was 0.887, and the index m 2 of C D was −0.162. Hence, a modified Turian–Yuan heterogeneous resistance model was obtained. The model verified that the minimum value of the regression coefficient, R 2 , of the simulated value reached 0.9701, proving that, the model can be used to simulate the heterogeneous resistance of urban sludge pipeline transportation.

Sludge pipeline transportation is increasingly used in different fields. Flow resistance is an important influencing factor in the pipeline transportation of solid-liquid two-phase flow slurry, and studying its characteristics is of great significance for optimizing pipeline design, reducing pipeline erosion and wear, and reducing transportation energy consumption. In view of the complexity of sludge as the resistance characteristics of solid-liquid two-phase flow, it is often necessary to analyze the inline mechanism of solid-liquid two-phase flow in slurry with the help of high-precision turbulent flow model in computational fluid dynamics (CFD), which has become the research focus of heterogeneous solid-liquid two-phase flow pipeline transportation. This paper analyzes and summarizes the CFD simulation status of heterogeneous solid-liquid two-phase flow resistance in pipelines, points out the future research direction, and provides reference for the analysis of heterogeneous flow resistance of sludge pipeline transportation and the optimization design of conveying system.