Numerical Simulation and Optimization Design for Magnetic Fluid Sealing Device
In this paper the principle of magnetic fluid seals is discussed. Based on the finite element software ANSYS, the magnetic field of magnetic fluid sealing device with three slots and four pole teeth is analyzed, and the size parameters of magnetic fluid sealing pole are optimized. The results show that the difference between the maximum and minimum intensity of magnetic field in the area near the shaft determine the sealing capacity of sealing device. The gap of seal should not be larger than 0.3mm. The optimized parameters which are provided for practical design can increase sealing capacity of sealing device as well as decrease the volume of sealing device.
Magnetic‐field analysis of ferrofluidic seals for optimum design
Ferrofluidic devices have found applications in laser systems, high‐vacuum equipment, computers, loudspeakers, inertia dampers, and motors. With the technique of magnetic‐fluid sealing, one is called upon to produce custom solutions for complex and diverse seal problems, many of which may be characterized by very hostile environments, wide temperature ranges, and intense radioactive conditions. In designing a magnetic circuit for a magnetic‐liquid seal, a number of factors, such as the size of the available envelope, pressure differential across the seal, chemical compatibility with various environments, and proper selection of permanent and soft magnetic materials need to be considered for achieving the most cost‐effective solution while meeting the entire range of requirements for any specific application. In order to evaluate flux leakage and fringing while accounting for nonlinear characteristics of magnetic materials, it becomes necessary to resort to numerical techniques to determine the effect caus...
First diamino Daphniphyllum alkaloid, daphnipaxinin, with an unprecedented heterohexacyclic skeleton from Daphniphyllum paxianum.
[structure: see text] The first diamino Daphniphyllum alkaloid, daphnipaxinin (1), with an unprecedented hexacyclic fused skeleton, along with a known alkaloid, daphnicyclidin A (2), was isolated from the stem of Daphniphyllum paxianum Rosenth. The structure and absolute stereochemistry of 1 were established by spectral methods, especially two-dimensional NMR techniques and CD analysis.