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Large hyperbolic cooling towers are mainly used in electric power, petroleum, nuclear energy, mining and other industries. In recent years, with the rapid development of China's national economy, these industries has been rapid development of large cooling towers are also a large number of construction. Type of shell rotating structure height, body mass, weight light characteristics, wind loads become one of the main load control structure design. The general specification of the reference data for the single tower of wind load, but the actual, the cooling tower is generally flocks construction, the interference effect between the tower and the tower with its wind so that in some cases much larger load than the single column, Therefore, the interference effect is necessary. Firstly, two kinds of rough quantity and five rough strip thickness analysis model of surface roughness on the impact of the cooling tower wind load, wind pressure point application of proper orthogonal decomposition (POD) encryption and Reconstruction, analysis of different rough the degree of cooling tower under wind pressure distribution and the overall force, and the test results with the specification, the previous measured and the results of wind tunnel tests to compare. Study found that the more smooth the surface of the cooling tower model, throat near the measuring point of the layer B is the maximum absolute value of the negative pressure greater; When the rough surface of the model, the number increases, the bottom of the cooling tower becomes larger shear coefficient by the greater the overall wind resistance; drag coefficient of the cooling tower near the neck and specification data close to the top and the middle and lower drag coefficient than the spec, needs to cause the attention of the design. In order to study the effect of interference of the cooling wind load in the case of the twin towers and three towers, by increasing the model of surface roughness in order to test Reynolds number effect of the compensation model. Calculate the the single twin towers drag coefficient and lift coefficient, and analyze its interference coefficient tower spacing, the variation of wind direction. The study showed that: the single-tower case, the average drag coefficient, the average lift coefficient is zero, considerable drag coefficient and the root mean square of the lift coefficient data; Twin Towers case, the average drag coefficient and maximum value corresponding interference coefficient almost the same, in most cases, the maximum value of the lift coefficient of the interference coefficient is greater than 1, up to 1.87 to the largest data. Three-tower case, most of the interference coefficient downwind to the bottom of the shear the average and maxima are less than 1, the distribution of the three towers of a triangle was inverted to form a barrier to the air channel, so after the tower by the overall resistance becomes smaller . Most of the interference coefficient across-wind base shear maxima over 1, the maximum value of close to 2, indicating that the the Three Pagodas case across wind ripple effects are very significant. Meanwhile, we also study the problem of the joint action of the cooling tower in the internal and external pressure. The studies show that the model bottom opening or not external pressure almost no effect, while the internal pressure has a great influence of the bottom opening when the inner surface of the pressure coefficients of -0.4 unperforated-O.7. Internal pressure equivalent to role of isotorus pressure on the surface of the meridian to the film stress and radial displacement almost no effect, while the annular film stress. Finally, the case of the twin towers and three towers, cooling tower wind-induced response of the average and maximum value of the interference factor of different towers spacing and wind down the conversion rule. The study found that the interference effects of the interference effects of wind-induced response of wind load, two interference effect of the law is not consistent.
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