The Study On The Hydraulic Performance Of Micro Water Jet Pump

Micro water jet pump is designed based on axial-flow pump, and is intergrated with a driving motor using magnetic coupling. The pump serves as the propulsion system for underwater glider, which is used for submarine detection. Design of micro pump structure, as well as the study on the hydraulic characteristics is aimed to simplify the structure of the system and improve the endurance, so that the pump can meet the strict requirements for size and the weight of the application of underwater glider.This dissertation discusses the relevant technology of the hydraulic design and structural design of the micro water jet pump, including the use of radial inlet, axial outlet arrangement, using the circular arc method and the streamline design two sets of micro jet propulsion pump hydraulic models. Internal flow field of the pump especially the pressure and velocity distribution are analyzed by using the CFD method, which clarifies the intrinsic reasons to the hydraulic performance change of the pump. At the same time the author gives the optimal nozzle model to improve the propulsion efficiency as the follow-up test model.In order to avoid the calculation error of the output power of the motor, the work characteristic test of the DC motor has been carried out. This paper specially built external characteristic test platform for collecting and measuring pressure, flow and other parameters. Analysis of external characteristic test result shows that, the overall efficiency of the hydraulic model with streamline design is higher than the hydraulic model with circular arc design.In order to make the micro injection pump to adapt to different conditions and maintain high efficient operation, this paper has carried on the variable speed regulation of numerical simulation and experimental research. The results show that the rotating speed of the pump has an important influence on the power and efficiency, as the speed increases, the optimal efficiency area shifts to large flow area, peak efficiency also increases. Finally the micro water jet pump can always run under the condition of optimal efficiency by optimization control of rotating speed, which can improve the run duration under different application environment and circumstance.