Research On Air Distribution Of Hot Air Jet Units In Tall Factory Building

When heating by traditional methods in winter,due to the effect of thermal buoyancy,the hot air rises,the upper temperature of the tall plant is higher than the lower working area,the vertical temperature stratification is obvious^[35],the heating effect is poor and the energy consumption is large.The heating and energy saving of tall buildings have not yet been resolved,and still need attention.In this paper,we continue to explore the form of airflow in hot air heating in a large factory building.It is the goal and task of this paper to obtain an airflow scheme with good heating effect and low energy consumption.Based on literature research and numerical simulation,the author proposes a new air distribution model for hot air jet units in tall buildings based on vertical wall attached jet and collision jet.When the air supply Angle is 30°,45°and 60°,the jet set is 3?8m away from the side wall and the air supply height is 16m,the flow field distribution in the workshop is analyzed.It is concluded that when the distance L=6m between the jet unit and the side wall and the air supply Angle is=30°,the hot air supply effect is the best.It is also found that the new air distribution mode of hot air jet unit in tall factory building is a ventilation mode that absorbs the advantages of vertical wall attached jet and collision jet.The energy utilization rate is high,and the hot air flow forms an air lake with appropriate temperature and speed in the space below the factory building,and the wind sense is weak.Further study is made on the distribution of the flow field in the new type of airflow organization of the hot air jet unit in the large factory building when the air supply temperature t₀=35??70?.It is found that when the supply air temperature t₀>55?,the hot air at the position of x=20m is gradually affected by the thermal lift and tends to float upward.The hot air is greatly influenced by the hot floating lift at the position where the line x=25m?30m,and the hot air floats obviously.The average air temperature in the working area gradually increases with the increase of the supply air temperature t₀,and the average temperature in the working area increases by 0.7?for every 5?increase of the supply air temperature t₀.Based on the research on the new air distribution model of hot air jet unit in tall factory building,the author further optimized it.A deflector was added to the side wall of the impact with the hot jet to study the influence of the deflector's inclination Angle,width w and length l on the flow field in the factory building.It is found that when the deflector tilts at an Angle of about 30°,it has a good deflector effect on the hot jet.When the width of the deflector plate is 0.4?0.6m,it has a good deflector effect on the hot jet.In order to save the space in the workshop,it is suggested to choose w=0.4m.The diversion effect is best when the length of the guide plate is 1.5?2m,not too long or too short.