Trial Manufacture of Sheet Former for Molten metals by means of Electromagnetic Force

设计了一种利用电磁场形成金属液薄膜流的装置。通过汞实验和近似分析，研究了磁场作用下导电流体的形状，得到以下结论：均匀垂直磁场下非圆形喷嘴喷出的液态金属射流：从非圆形喷嘴喷出的射流的横截面形状沿流方向振荡。然而，在具有均匀垂直磁场的情况下，这种振荡被高度抑制。非均匀垂直磁场下的液态金属射流：磁场梯度改变了射流的形状，使射流像固体壁一样作用，而不与流体接触。负磁场梯度作用下射流变宽，而正磁场梯度作用下射流形状变长。喷嘴越宽，宽度变化越大；然而，厚度变化几乎不受初始宽度的影响。非均匀横向磁场下的液态金属液流：在没有磁场的情况下，液流的宽度和厚度都没有变化。当向流方向施加非均匀横向磁场时，厚度沿流方向明显减小，但宽度增加。总的来说，电磁力使水流变平了。当施加强磁场时，自由表面上的扰动被阻尼掉，而流的表面呈现镜面状。从导电喷嘴喷出的液态金属射流在均匀垂直磁场下：当液态金属射流从导电喷嘴喷出时，射流被拉伸到磁场方向。

The apparatus for forming thin film flow of molten metals by means of electromagnetic field was devised. The shape of electrically conducting fluids under a magnetic field was studied by experiments with mercury and by an approximate analysis, and the following conclusions were obtained.1. Liquid Metal Jet Issuing from Noncircular Nozzles under a uniform Vertical Magnetic Field: The cross-sectional shape of the jet issuing from a noncircular nozzle oscillates along the streamwise direction. However, in the case with a uniform vertical magnetic field, this oscillation is highly suppressed.2. Liquid Metal Jet under a Nonuniform Vertical Magnetic Field: The magnetic field gradient changes the jet shape and acts no the jet like a solid wall, without coming into contact with the fluid. A jet is widened under a negative magnetic field gradient, while, a jet is changed in shape to be longer than it is wide under a positive one. When the nozzle is wide, the width change becomes larger; however, the thickness change is hardly affected by the initial width.3. Liquid Metal Rivulet under a Nonuniform Transverse Magnetic Field: Without a magnetic filed neither the width nor the thickness of the rivulet changed. When a nonuniform transverse magnetic field decreasing in the streamwise direction is applied to the rivulet, thickness decreases considerably along the flow, but the width increases. On the whole, the rivulet is flattened by the electromagnetic force. When a strong magnetic field is applied, disturbances on the free surface are damped out and the surface appearance of the rivulet is mirrorlike.4. Liquid Metal Jet Issuing from Electrically Conducting Nozzles under, a uniform Vertical Magnetic Field: In the case that liquid metal jet issues from an electrically conducting nozzle, the jet is stretched to the direction of the magnetic field.