Study On The Flow Characteristics Of Gas-liquid Two-phase Flow In The Process Of Welding Flue Gas Bath

Water bath dedusting has a series of advantages such as high efficiency,low cost and low energy consumption.It is widely used.The welding operation produces a lot of harmful derivatives,which seriously affects the health and pollution of the welding workers.In the field of welding flue gas purification,water bath purification is a new technology.According to the actual situation,the cleaning device is built and designed,and the dust removal mechanism and the multiphase flow are discussed.In this paper,using software ICEM mesh was carried out on the physical model,based on FLUENT software,the volume model(VOF),the purification device with RNG k-? turbulent model a numerical simulation of the internal flow field obtained pressure and turbulent kinetic energy,velocity field and gas phase concentration distribution rule,the results show that the device internal pressure distribution in vertical distribution is layered formation pressure gradient,in the process of welding fume baths,pressure distribution in the transverse volatile,around the intake pipe pressure changes significantly greater than near the wall pressure;In the vicinity of the inlet pipe,the turbulent energy of the gas phase and the liquid phase are exchanged violently,and the turbulent kinetic energy is gradually weakened with the floating of the bubbles.The most atmospheric velocity is distributed near the inlet pipe,and the distribution of gas phase and liquid phase velocity is uneven,forming a chaotic turbulent flow.The air bubble is increased along the inlet pipe by the buoyancy and the inverse pressure gradient,and the gas bearing rate near the inlet pipe is higher than that of the wall near the device.In the case of changing operation parameters,the gas speed is higher and the gas-belt liquid is serious.The air speed increases the air bubble and the gas holdup increases.With the increase of the tone velocity,The most atmospheric velocity distribution in the upflow zone begins to shift toward the inlet pipe,and the sides of the wall show a lower trend.The influence of the two phase flow of the gas liquid in the purification device is studied by the design optimization of the structure of the water bath system.Results show that the drainage tube length in the range of 0.06 m to 0.06 m for optimal,with guide gas spreading dust control center,at the same time within the scope of this formed the dual cycle flow has the very good impetus liquid flow;The partition of the aperture of 0.01 m is optimal for the gas rectification and the crushing bubble.When the spacing of the partitions is 0.12 m,the gas content of the two partitions is evenly distributed.The 5-stage bulkhead will maintain a certain value,while making the gas stay in the device longer,increasing the contact time of the gas liquid,and the gas liquid will be mixed evenly in the radial direction.Finally,through experiment simulation verification,by the method of camera,validate the process of welding fume baths,experimental results are consistent with the simulation results concluded that the results of the welding smoke purification plant design has a guiding significance.