Papers by Keyword: Coupled Field Analysis

Abstract: Annular electromagnetic stirring (A-EMS) process is an advanced semi-solid metal processing technology. It could avoid the effect of skin effect, increase the shear rate, reduce the temperature gradient and refine microstructures. A three-dimensional computational model sequentially coupling electromagnetic stirring with a macroscopic heat and fluid flow in A357 alloy semisolid slurry preparation by A-EMS has been developed. Comparison between microstructures of A357 alloy produced by EMS and A-EMS has been made. The results show that the annulus gap avoids the part of low magnetic induction intensity and A-EMS avoids the effect of skin effect. The annulus gap prohibits the circular flow and increases the shear flow. The circular flow is more effective than the shear flow on heat dissipation. A lower temperature difference in the stirred melt and subsequent uniformly fine microstructures were obtained as compared with the normal electromagnetic stirring.

Abstract: The bed is a main component of the large precision linear rolling guide CNC grinding machine tool. Its thermal-structure characteristics affect on machine tool’s machining precision and stability directly. In this paper, boundary conditions on the bed of a machine tool factory’s production are analyzed; using FEA method, the bed finite element models for thermal-structure coupling analysis are established and then calculated. By analysis, the simulation of the CNC machine tool operating conditions can effectively obtain the distributions of the bed temperature, thermal deformation and thermal stress; and the results are closed to the true situation.