| Magnetic drive pump is a new type of pump, combining modern magnetic theory and new sealing technology in common centrifugal pump.It uses magnetic coupling to transfer torque non-connect and to solve the problems of leakage caused by pump with shaft seal, so it is widely used in nuclear, chemical and other special industry. In recent years, with the development of computer technology, some theoretical results of magnetic pump have been gained. But there are still some technical problems discouraging the application of magnetic drive pump, such as the method of solving magnetic circuit accurately, eddy current, high temperature, monitoring, the materials of bearings and magnets, etc.The current situation and characteristics of magnetic drive pump were reviewed. Aiming at the transmission efficiency, the magnetic field and eddy current of magnetic coupling with different arrangement of permanent magnets were analyzed, using electromagnetic finite element analysis technology. This will provide basic theory for the research of high-efficiency magnetic pump. The main work and results of this research are as follows:1.The development and research situation of magnetic drive pump were summarized and analyzed briefly, and the specific research program was identified by analysis. The characteristics and basic principle of magnetic coupling were described. The main problems which need to be solved in the develop-process were pointed out.2.The causes, influential factors and control methods of magnetic drive pump's specific energy loss were analyzed. The methods of calculating energy power loss were summarized and common formulas for eddy current power loss which used in engineering were introduced.All of these formulas provided theoretical basis for the analysis of eddy current of magnetic coupling.3.The arrangement of permanent magnets of magnetic coupling was designed by AutoCAD.We analyzed the magnetic field characteristics of permanent magnets with different arrangement by ANSYS software. In order to improve magnetic field intensity, the Halbach array was applied to magnetic coupling.4.Based on the Maxwell equations, the 2D analytical models of magnetic coupling with different arrangement of permanent magnets were established by ANSYS. The air-gap magnetic field was calculated.Then the distribution of magnetic force lines, magnetic field intensity and eddy current of isolating shell were analyzed. The torque of magnetic coupling with different arrangement of permanent magnets was calculated.Compared with the coupling with traditional magnet arrangement, the coupling with Halbach array has a significantly improved torque.The impacts of angle deviation, air-gap, relative permeability of isolating shell,and thickness of permanent magnets and yoke irons on the transmission torque were analyzed.5.Transient analysis of eddy current field in the magnetic coupling was carried out. Then the eddy current power loss of magnetic coupling with different arrangement of permanent magnets was calculated.The influences of the thickness, radius, resistivity, relative permeability of isolating shell and the speed of magnetic rotor on the eddy current power loss were analyzed.
|
PDF Full Text Request