Numerical Simulation Of Flow Field In Mixing Flow Pump Of Double Volute And Dynamic Characteristic Analysis For The Impeller

With the unceasing development of science and technology, the modern industry and agriculture put all aspects of hydraulic machinery to a higher performance. If the cavitations are not very serious, the efficiency, intensity and stability are three most important performance indices without doubt. Efficiency relates to the utilization of energy, intensity relates to the life circle of impeller, which is the only acting part in the hydraulic machinery unit, and stability relates to whether the unit can be safe, normal movement. In fact, they are not mutually independent, but are related to closely in together. Therefore discussing the relations of the three important performance indices have become an inevitable and sensitive topic in the design process of hydraulic machinery.The article take a mixing pump of double volute as the object of study, and take the computation fluid dynamic as rationale, utilizes the advanced computer numerical calculus technology, and carries on the entire three dimensional steady turbulence numerical simulations under many operating points for the complete machine of mixing pump, also promulgates the dominant mechanism of its internal flow field under three kind of characteristic operating points. Meanwhile makes the essential optimized modification to the impeller in order to raise the efficiency under the design operating point. For discussion mixing pump unit's stability, also carries on the unsteady turbulence numerical simulations to the above computation model under the design operating point, analysis pressure oscillation changes with the time to test points in its interior flow field in detail. In addition, massive literature report the impeller of hydraulic machinery unit receives the fatigue damage which continues, the blade has the crack or break phenomenon, and the entire unit is also following the intense vibration and the mechanical noise. Regarding it, this article applies the fluid solid coupling technology to carry on mechanics characteristic analysis about the static rating and modality to the impeller of mixing pump, it can provide some references for the flow passage components' intensity design and the examinations, also the vibration analysis for the entire pump unit.Considering the above factors, we must note clearly that we should not pursue only the efficiency constantly in the design stage of hydraulic machinery, but should take into consideration the restriction about the intensity and stability, and should set a goal that developing products of hydraulic machinery which not only have higher effective and can conserve energy, but also can move steadily, safely and reliably in order to consummating their structure and improving the performance unceasingly.