Characteristics Of Wind Load On Large Steel Tanks

Steel tanks are the main facility for storage of oil, With energy consumption is increasing and land resources lack,The volume of steel tank is more and more big.The construction of large steel tanks is becoming more and more popular. On the other hand, large steel tank is a thin-walled steel structure and prone to wind-induced buckling failure. In recent years,this failure are common. Worthy of note is that of large steel tanks wind damage will not only caused huge economic losses, but also cause serious environmental pollution. In order to improve the wind resistance performance of the large steel tanks. Firstly, this paper from the basic principle of bluff body aerodynamics of Reynolds number effects on wind loads of low circular cylinder was studied; Based on this, wind load characteristics of typical large steel tanks was studied. The main work includes the following aspects:1) Reynolds number effect of wind load of low aspect ratio circular cylinder. Selection of low height to diameter ratio were0.875and0.323as the object of study, Get wind pressure distribution of circular cylinder in four kinds of turbulent flow field at different wind speed.Evaluated the effects of Reynolds number,ratio of height to diameter and turbulence on the low height to diameter ratio cylinder. The results show that the cylinder Reynolds number effect in decrease with the height to diameter ratio decreases,in increases to flow turbulence so as to reduce the low aspect ratio cylinder Reynolds number effect.2) Wind load characteristics of large steel tanks. Typical external floating roof steel tank as the research object, Get wind pressure distribution of external wall and interior wall in different height to diameter ratio,location of floating roof and the cases of wind gird. The results show that with decreasing in height to diameter ratio, zero pressure angle increases, cross wind on the tank surface and leeward side of the wind pressure coefficient with the absolute value decrease; the absolute value of wind pressure coefficient on the inner wall of the tank increase with the tank height to diameter ratio increases; regulations for shape factor of wind load in the height to diameter ratio equal to1is no longer applicable to tank structure design; position of the floating plate can influence the air pressure of the external wall of the tank smaller, effect on the interior wall of the tank pressure greatly,especially elevation of floating roof position can reduce the wind pressure of interior wall at larger height to diameter ratio of tank in the windward region, increases the wind pressure of interior wall at smaller height to diameter ratio of tank in the windward region, This situation is very bad for the large steel tank; the effect of the different cases of wind gird for wind pressure of external wall is small. we can ignore the effects of wind gird.3) Wind pressure interference effect of large steel tanks. The typical tank group was selected as the main object of study, and the wind pressure distribution of the wall of tank was obtained. The results show that when the disturbed tank is located in the upstream of the wind direction, the interference effect of wind pressure on wall is smaller; When the disturbed tank is located in the downstream of the wind direction, the interference effect of wind pressure on wall change significantly; Increasing the spacing between tanks can reduce the interference effect between tanks; Disturbed storage tank is the most obvious interference of adjacent storage tank.