In order to study the wind pressure distribution characteristics of rectangular roof structure, the canopy gas station as the prototype manufacture of 1:20 scaled model, pressure test was carried out under the typical...
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In order to study the wind pressure distribution characteristics of rectangular roof structure, the canopy gas station as the prototype manufacture of 1:20 scaled model, pressure test was carried out under the typical suburb wind field in wind *** roof was divided into different bands according to the flow characteristics. Firstly, qualitative analyse the distribution of the mean wind pressure on structure's ***,choose different measuring points in bands,analyse power spectral density function in frequency domain and correlation coefficient in time domain of the wind *** results show that the upper surface pressure distribution is mainly affected by the columnar vortex separation and lower surface wind pressure distribution is related to the interference of column,the surface net pressure distribution was affected by both columnar vortex separation and support *** of wind pressure is weakened in the windward front local region of the structure and the wake region of the support column. The wind pressure power spectrum of the structure surface is mainly related to the relative position of the flow,the support column increases the wind energy in the front and rear regions,which is harmful to the structure.
The non-Gaussian characteristics of local wind pressure of typical gable roof of low-rise building with a slop angle of 18.4° were monitored by means of the wind tunnel test under terrain roughness regimes of A,B...
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The non-Gaussian characteristics of local wind pressure of typical gable roof of low-rise building with a slop angle of 18.4° were monitored by means of the wind tunnel test under terrain roughness regimes of A,B and C. The probability density distribution features of wind pressure coefficient series are investigated, the characteristics of non-Gaussian zones distribution of wind pressure relative to different wind angles and different terrain conditions are analyzed and the relationships between non-Gaussian pressure and distinctions of flow field on roof are discussed. The studying results indicate that GEV distribution and Gamma distribution fit the probability density distribution of wind pressure coefficient better than Gaussian distribution and Lognormal distribution, but the fitting effect for long trailing tail part is undesirable, when skewness and kurtosis are large in magnitude(absolute value). The variation of terrain roughness and wind directions have significant influence on the distribution of non-Gaussian pressure regions on low-rise building roof. Under the oblique wind direction, the Gaussian pressure zone is divided into three sections along the approaching wind direction, along which the areas move with the change of terrain roughness regimes. The non-Gaussian features of wind pressure is positively related to mutual correlation coefficient of it's time-history.
A RNG k-e model,the Reynolds Averaged Navier-Stokes Equations(RANS) turbulence model, was added in software Fluent 6.3 to simulate the wind tunnel model of Tokyo Polytechnic University and the simulating results were ...
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A RNG k-e model,the Reynolds Averaged Navier-Stokes Equations(RANS) turbulence model, was added in software Fluent 6.3 to simulate the wind tunnel model of Tokyo Polytechnic University and the simulating results were compared to the wind tunnel test data. Then a detailed parametric study is performed for average pressure coefficient of two low-rise gable roof buildings in the same shape which only change the angle of the downstream building. The results show that the mean wind pressure coefficient of upstream building is hardly affected by the angle changing of the downstream building when the distance between buildings is larger than twice of building's width, while the downstream building is affected relatively large especially at the corner area of ridge at small angles.
Through the wind tunnel test on the opening of different locations and local areas in vulnerable areas of low-rise building roofs, the distribution characteristics of wind pressure inside and outside the roof caused b...
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Through the wind tunnel test on the opening of different locations and local areas in vulnerable areas of low-rise building roofs, the distribution characteristics of wind pressure inside and outside the roof caused by roof damage. The results show that the influence of the wind direction angle on the internal pressure caused by the wind is obvious, and the internal pressure caused by the opening on the leeward surface is small and the change law is obviously different from that on the windward surface. The correlation coefficient on the inner side of the roof opening is higher than that on the side of the unopened roof, and the correlation between wind pressure on the measurement points near the opening is larger than other regions.
Based on Galerkin method and multiple scales method, the first-order symmetric mode responses the suspension cable under longitudinal time-delayed velocity feedback control are obtained. The influence of system parame...
Based on Galerkin method and multiple scales method, the first-order symmetric mode responses the suspension cable under longitudinal time-delayed velocity feedback control are obtained. The influence of system parameters, such as time delay, control gain and excitation amplitude on the controlled system, is investigated by the numerical examples. According to the feedback gain increasing, the amplitude of the system response is significantly suppressed. And the efficiency of vibrationcontrol can be improved by selecting control gain and the time-delay value.
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