| The cooling tower is a device that uses the circulating cooling water to discharge the useless heat generated by the system into the atmosphere.Cooling tower plays a very important role in the industrial production.Cooling tower is a kind of high-rise and thin-walled space structure,wind load is one of its control loads.The current code only specifies the standard value of equivalent wind load of the traditional hyperbolic concrete cooling tower below 190 m.It does not mention the wind pressure distribution and the value of wind vibration coefficient of the steel structure cooling tower,nor does it ind icate whether the average wind pressure distribution coefficient of the co de is applicable to the cylinder-frustum cooling tower.In this paper,the values of the average wind pressure distribution coefficient and the wind vibration coefficient of the new type steel structure cooling tower are studied.The main work is as follows:Three rigid scaled models were processed,and the wind tunnel test of rigid model was carried out under various conditions.The influence of different surface roughness,wind speed and other variables on the distribution of the average wind pressure coefficient of the cooling tower is studied,and the differences between the new shape of cooling tower and the traditional hyperbolic cooling tower are compared.The characteristics of the average wind pressure coefficient of the cylinder section and the frustum section of the cooling tower are compared,and the suggestion of the average wind load value of the new type cooling tower is put forward.The wind pressure distribution and three-dimensional flow around the thin shell of cooling tower with full-scale structure are analyzed by using CFD numerical simulation.Compared with hyperbolic cooling tower and cylinder-frustum cooling tower,the wind pressure distribution is similar.The distribution of wind pressure on the outer surface of cooling tower is different with different surface coarse particles.By comparing the surface roughness of steel structure and concrete cooling tower,the suggestion of the average wind pressure distribution coefficient of steel structure cooling tower with smooth surface is given.The analysis of flow characteristics shows that the performance of cylinder-frustum cooling tower to promote air flow is similar to that of hyperbolic cooling tower.By using ANSYS software,the cooling tower model of pyramid system with different tower height and different ratio of frustum height is established.The time history data of wind tunnel test is transformed into the structure model,and the displacement response and support reaction response of structural joints in different directions are analyzed.The wind-induced vibration coefficient of the structure is calculated.According to the statistical results,the recommended value of wind-induced vibration coefficient of the pyramid system cooling tower under 220 meters is proposed. |
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