Numerical Simulation And Inlet Pro-swirl Transformation Of Desulfurization Slurry Pump Of Thermal Power Plant

This thesis, research object for large thermal power plant’s desulfurization slurry circulating pumps, slurry pumps are an important part of the flue gas wet desulfurization system (FGD) of thermal power plant, and directly affects the desulfurization efficiency and economy of FGD. Operating working fluid of slurry pump is limestone slurry, the impeller entrance prone to significant erosion and wear, in view of this reason, this study analyzes the reasons for wear and erosion slurry pumps, and using the Fluent software to numerical simulation. By prototype pump, proposed the slurry pump slurry inlet pre-swirl transformation research programs, and conduct numerical simulation study. Aimed at improving slurry pump resistance to wear and corrosion, also the safe and stable operation performance. The main research work and creative results are as follows:(1) From the theoretical design, experimental research, numerical simulation calculation and comprehensive study summarized the current research status of solid liquid two phase flow pump, this paper briefly describes the mechanical blades based on the development of numerical simulation and the key problems. For the article research object-desulfurization slurry circulating pump, reviewed its development frontier in the power plant, the current application situation and the existing problems.(2) According to the problem of slurry pump, go to the field of surveying and mapping entity pump, surveying and mapping data are collected, and the use of AutoCAD for slurry pump impeller and the drawing of blade, the 3d model and drawing optimization model is established. Using Gambit software, meshing and optimization of the model, set the boundary conditions.(3) By using Fluent software, the use of multiphase flow model, using the conventional numerical algorithm of numerical calculation was carried out on the prototype pump, the result shows:the impeller outlet wear the most serious of the slurry pump, impeller inlet is the worst place of cavitation, uneven fluid vibration and the flow field of brings to the pump body vibration, these phenomena influence each other, gradually deepened; volute lateral and volute tongue was wear and run for a long time will seriously affect the performance of the slurry pump.(4) In this paper, the optimization scheme, let into the impeller of slurry to produce proper prewhirl along the impeller rotation direction, optimization of numerical simulation results show that:To eliminate the flow offset caused by the reverse flow, so that the slurry is applied to a small reverse flow along with a positive pre-swirl together pre-swirl, completely avoid the caused by a defect of the reverse flow exists; The impact of the impeller exit is reduced, wear is improved, while reducing the impact of losses and friction losses; The slurry pump NPSH reduce can improve pump cavitation and vibration excitation caused by fluid; The reasons for the operation of the prototype pump produces erosion analysis is correct, compliance with the plant operation, and its transformation program is successful.Leading to the conclusion:Select a reasonable model and suitable inlet slurry pre-swirl, can guide the design of research and engineering transformation of slurry pump in thermal power plant.