Physical Simulation Study On Flow Field Containing Dross In A Continuous Hot Dip Planting Pot

Continuous hot-dip galvanizing is a prevalent method of sheet glavaninzing.Its production is widely used for shape manufactuing of automotive and home appliance.So high surface-quality is required.Howerver,in the continuous hot process,zinc dross formed in zinc pot easily adhere to the surface of the steel strip,seriously degrading surface-quality.Detailed study of flow characteristics and bottom dross distribution is needed to resolve surface-quality problem.Pratically,physical flow and numerical simulation is conducted to study flow characteristics.In this study,the experimental prototype is based on a real zinc pot in the continuous hot-dip galvanizing line.A theorical framework of flow pattern containing dross is put forward.A 1/5 transparent water model was designed and manufactured.Simulation particles are chosen according to forecast experiments.Finally,ABS particles are selected as the simulation particles of zinc doss.Meanwhlie,Nacl aqueous solutions is utilized as models for the planting melts.The motions of dross in the pot are observerd after the flow becomes steady using a high-speed video camera.The dynamics stacking pinciple of bottom dross is summarized.The influence of experimental parameters on flow pattern,shape of bottom dross and critical speed is invetigated.The main works of this paper are:(1)Theorical framworks based on particle Reynolds number and modified Fround number are raised.The sedimentation experiment of simulation particle in different kinds of liqiud is designed to measure particle Reynolds number.Two forecast experiments,in the situation of different parameters and simulation particles,are performed.In the end,ABS particles satisfy the experiment requirements and are employed as simulation particles;meanwhile,Nacl aqueous solutions are utilized as models for the planting melts.(2)ABS particles and Nacl aqueous are employed in the simulation experiment.The flow fields is recorded by a high speed camera and drown according to the video.The whole pattern differs with inductor open and closed.Dross accumulated on junction between strip and front support rolls,back of snount and opening of front support roll motor.Flows genetated from junction between strip and front support roll and sink roll without strip impact bottom dross.(3)Dynamics stacking principle of bottom dross and critical speed are researched.Bottom dross in front region is impacted or stacked depanding on strip width.The degree of impact lies on strip velocity.The asymmetry of bottom dross shape is aroused by asymmetric layout of two inducors.The relationship between critical speed and running time is linear and bilinear.