Research For Non-overload Performance On Large-scale Medium Specific Speed Mine Pumps

Coal mining is often along with water gushing that will endanger the safety of life and property, so the mine drainage pumps play a crucial role in mine working. To finish the drainage task, the mine drainage pumps often work at high flow rates, so overloading accidents may occur frequently. So it is necessary to research the non-overload performance of the mine drainage pumps. In this paper, a medium specific speed pump D82-19-2 was taken as the research object. The model pump experiment, numerical simulation, orthogonal test scheme and optimal design formulas were carried out respectively. The infuuence of the geometrical parameters in non-overload performance was exploed, and the final optimal scheme was found. Details of research were as follows:1. The performance of the model pump was predicted and tested.The 3-D model was established using the hydraulic design software of FanFang, and the numerical simulation results were carried out by the Fluent to predict the performance. To verify the accuracy of the simulation result, the experiment was done. The numerical simulation results were basically in agreement with the experiment results, showing the effectiveness and reliability of numerical calculation.2. The influence of geometrical parameters in non-overload performance of the medium specific speed centrifugal pump was explored.By choosing seven factors, β2、D2、z、b2、Dj、Ft、φ and three levels for each factor, a L18(37) orthogonal test was designed. Then, the model was established for numerical simulation. So the influence of geometrical parameters in non-overload performance was analyzed, and the orthogonal optimal scheme can be obtained based on the analyzed result.3. A formula for the optimal design of impeller of medium specific speed non-overloaded pumps was derived.According to traditional design formula of medium and high specific speed non-overload centrifugal pump, a formula for the optimal design of impeller of medium specific speed pumps was derived based on the theory of non-overload. Two examples of design were showed on pumps D82-19-2 and D200-50(P)-0105 a and the results show that the optimal formula is feasible. An optimal formula design scheme was obtained.4. The final optimal scheme was proposed and the performance of the prototype pump was obtained.Comparison with the original scheme, the orthogonal optimal scheme and the optimal formula design scheme, the final optimal scheme was obtained. Based on the theory of resemble conversion, the geometrical parameters of the prototype pump was obtained. By numerical simulation, the results show that the performance of prototype pump was in agreement with the design requirement.