Influence Of Air Supply System In Welding Workshop On Local Working Environment

In the welding process,the welding workshop will produce a large amount of welding fumes,as well as light pollution,radiation,and noise.This will not only harm the health of welding workers,but also affect the production efficiency.This project takes the actual project case as the background,and the research object is the influence of a ventilation system of a welding workshop in Zhengzhou on the operation environment of the local station.The welding workshop adopts high-temperature gas infrared radiant heating in winter and is affected by the negative pressure fan.The heating effect is not good,and the actual temperature in the workshop can only reach 6°C.After on-site investigation and extensive data access,the new wind hot air heating program was proposed to improve the welding environment in the welding workshop.In this paper,the design and theoretical calculation of the new wind hot air heating system are firstly carried out,which lays a certain foundation for the subsequent numerical simulation study.Next,according to the actual circumstance of the welding workshop,the large top leather welding station is selected as the numerical simulation area,the physical model is built by ICEM and the grid is divided by structured grid,the influence of the new wind hot air heating system on the ambient temperature,velocity field and concentration field in the local work station of the welding workshop is studied through CFD method.the temperature field and velocity field in the local work station of the welding workshop are numerically simulated by changing the air supply parameters of the new wind hot air heating system.And it is found that when the installation height of the air supply port is higher than the height of the air intake shutter(the height of the air intake shutter is 2.5m),hot air loses heating effect due to cold wind blocking.Proper adjustment of the overall air intake angle(by adjusting the angle of the louvers of the inlet shutters)can improve the influence of cold air on the work environment of the welding station.The average temperature of the welding station and the entire welding workshop increases with the increase of supply air temperature.The average temperature and flow rate at the welding station increase with the increase of air supply speed.The temperature and the flow velocity at the welding station are unevenly distributed when the air supply angle is reduced,and when the air supply angle is increased,the heating effect is not good.The numerical simulation study of the welding fume concentration field in the welding workshop is conducted by changing the mechanical ventilation volume.It is found that when the welding workshop only uses full ventilation to remove welding fumes,the single fan exhaust volume of 25000 m3/h can meet the purpose of removing welding fumes.In order to study whether the new wind hot air heating system has a positive effect on the elimination of welding fumes,a numerical simulation is performed under the background of a single fan exhaust volume of volume of 20000 m3/h.It is found that the new wind hot air heating system has a positive effect on the removal of welding smoke at the welding station,and is less effective than the overall ventilation effect in reducing the overall welding fume concentration in the welding workshop.Through numerical simulation,this paper verifies the feasibility of the new wind hot air heating system applied in the high-sized workshop,and provides certain reference for the heating and ventilation dust removal methods in the welding workshop.