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In this work, A 3-dimensional model is developed to investigate fluid flow in a magneto-hydrodynamic micropump. The equations are numerically solved using the finite volume method and the SIMPLE algorithm. This study analyzes the performance of the magnetohydrodynamic micropump. For this purpose, a magnetohydrodynamic micropump built in 2000, is simulated. The micropump has a channel with 20mm length, width of 800 , height of 380 and an electrode with 4mm length. The applied magnetic flux density was 13mT and the electric current was different for various solution (10-140 mA). The results show that the intensity of the magnetic field, the electric current and the geometry has an effect on the magnetohyrodynamic micropump performance. By increasing the amount of magnetic flux and electric current the average velocity increases. decreasing the channel length would increase the mean flow velocity. by increasing the channel depth, the mean flow velocity initially increases and then decreases, while at a depth of approximately 700-800 the maximum averaged velocity will be resulted. The velocity increases by Increasing the channel width to 1500 , however the velocity remained unchanged for larger values.

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Surface quality and roughness are major effective parameters on the function of optic components. This study developed a new design of the Ball-End Magnetorheological finishing tool with the ability to mount on a three-axis CNC milling. In the new design, a new concept of the cooling system was used for cooling the internal and external surfaces of the electromagnetic coil, and optimizations on magnetic flux distribution were performed. With the aid of magnetostatic simulation in Ansys Maxwell software, the tool’s capability for producing magnetic flux density was tested. The capability of a new tool for polishing non-ferromagnetic BK7 glass was tested by selecting optimized process parameters like working gap and magnetizing current. An experimental magnetic flux density test with the gauss meter showed that the newly designed BEMRF tool can generate enough magnetic flux density for polishing BK7 glass. The finishing test showed the tool’s ability to create enough indentation force on the workpiece’s surface and reduce surface roughness.
 

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One of the components of the MAF process is the magnetic field that is applied through the field source. This source can be permanent or electrical. In terms of shape, permanent magnets are divided into two main categories: cubic and cylindrical. In the past researches, cylindrical overhead magnets have been used to perform MAF on free surfaces, which is not very efficient due to the time-consuming process. In this research, first of all, the methods of making overhead magnets have been examined to find the optimal magnetic conditions. Then, in order to increase the efficiency of the process, methods to increase the efficiency of the overhead magnet have been investigated. Based on this, the mentioned methods have been discussed and evaluated. According to the results, in the method of using a ball magnet and connecting it to a cylindrical magnet, the magnetism density is significant, and also by grooving the head magnet, the roughness changes on the inclined surfaces of the ferromagnetic workpiece from 21% to It reached 34.4% and in the inclined area with a curvature angle of 90 and 105 degrees of the surface of the ferromagnetic workpiece, a 9% increase in roughness changes occurs.