In this paper, we build an air conveyor with newly developed vortex bearing elements, and study the flotation precision of the front-end of the substrate in quasi-static flotation transport. We experimentally discuss ...In this paper, we build an air conveyor with newly developed vortex bearing elements, and study the flotation precision of the front-end of the substrate in quasi-static flotation transport. We experimentally discuss the three influential factors: air supply pressure, thickness of the substrates and installing direction of the vortex bearing element. We find that during the process of transport the movement of the substrate leads to the variation of flotation height. The amplitude of variation (e.g. flotation precision) is dependent upon the bearing stiffness and the suction force of the vortex bearing elements. Increasing air supply pressure properly can improve the flotation precision, but an excess pressure can cause over-suction due to high negative pressure and result in a poor flotation precision. We also know that the flotation precision of thin and light substrates are easily affected by the suction force of vortex flow because they float with a high flotation height and are more susceptible to deformation. Finally, we investigate four installing directions of the vortex bearing element. Different installing direction can lead to different variation of flotation height.展开更多
Stabilizing the interface wave of the molten aluminum(metal)-electrolyte(bath)is beneficial to shorten the anode-cathode distance(ACD)which is critical to the energy saving.A coupled mathematical model was developed t...Stabilizing the interface wave of the molten aluminum(metal)-electrolyte(bath)is beneficial to shorten the anode-cathode distance(ACD)which is critical to the energy saving.A coupled mathematical model was developed to study the impact of the novel cathode protrusion on the molten fluid motion as well as the metal-bath interface deformation.The molten fluid motion in the aluminum reduction ceils is under the combined effect of the electro-magnetic forces(EMFs)and the gas bubbles generated at the anode.A transient inhomogeneous three-phase model(metal-bath-gas bubble)was established in order to calculate more accurate.The results indicate that the metal-bath interface deformation can be reduced significantly by the novel cathode protrusion which is beneficial to the electric energy saving.Besides,The EMFs decreases as a result of the optimizing of the magnetic field due to the novel cathode convex which is an important driving force for the deformation of the interface.In addition,large vortex in the metal flow field is break up into the small vortex by the cathode protrusion and then dissipated due to the viscous force and the hindering effect of the cathode protrusion.The quantity of the vortex as well as the strength of the vortex reduces significantly in the reduction cell with novel cathode protrusion.展开更多
文摘In this paper, we build an air conveyor with newly developed vortex bearing elements, and study the flotation precision of the front-end of the substrate in quasi-static flotation transport. We experimentally discuss the three influential factors: air supply pressure, thickness of the substrates and installing direction of the vortex bearing element. We find that during the process of transport the movement of the substrate leads to the variation of flotation height. The amplitude of variation (e.g. flotation precision) is dependent upon the bearing stiffness and the suction force of the vortex bearing elements. Increasing air supply pressure properly can improve the flotation precision, but an excess pressure can cause over-suction due to high negative pressure and result in a poor flotation precision. We also know that the flotation precision of thin and light substrates are easily affected by the suction force of vortex flow because they float with a high flotation height and are more susceptible to deformation. Finally, we investigate four installing directions of the vortex bearing element. Different installing direction can lead to different variation of flotation height.
基金Item Sponsored by the National Natural Science Foundation of China[NO.50934005 and NO.50904014]
文摘Stabilizing the interface wave of the molten aluminum(metal)-electrolyte(bath)is beneficial to shorten the anode-cathode distance(ACD)which is critical to the energy saving.A coupled mathematical model was developed to study the impact of the novel cathode protrusion on the molten fluid motion as well as the metal-bath interface deformation.The molten fluid motion in the aluminum reduction ceils is under the combined effect of the electro-magnetic forces(EMFs)and the gas bubbles generated at the anode.A transient inhomogeneous three-phase model(metal-bath-gas bubble)was established in order to calculate more accurate.The results indicate that the metal-bath interface deformation can be reduced significantly by the novel cathode protrusion which is beneficial to the electric energy saving.Besides,The EMFs decreases as a result of the optimizing of the magnetic field due to the novel cathode convex which is an important driving force for the deformation of the interface.In addition,large vortex in the metal flow field is break up into the small vortex by the cathode protrusion and then dissipated due to the viscous force and the hindering effect of the cathode protrusion.The quantity of the vortex as well as the strength of the vortex reduces significantly in the reduction cell with novel cathode protrusion.
