基于midas NFX的聊城铁塔CFD数值模拟研究OA

Taking the Longxing Temple Iron Tower in Liaocheng,a nationally protected cultural rel-ic,as the research object,a three-dimensional model of the iron tower was established on the basis of field measurements in view of the potential hazard of wind loads to ancient buildings.Using the midas NFX software and the SST k-ω turbulence model,CFD numerical simulations and finite element anal-yses were carried out.The results showed that the wind speed on the windward side increased with height,whereas that on the leeward side first decreased and then increased,with the peak value occur-ring at the tower tip.A low-wind-speed zone formed because of the obstruction of the iron tower,and the gradient attenuation reflected the wind-shadow effect.The pressure on the windward side first in-creased and then decreased from bottom to top,whereas a low-pressure zone formed on the leeward side because of vortices,which was consistent with the Bernoulli principle.The maximum displace-ment at the tower tip was 1.312 mm,and the displacement increased significantly above the sixth sto-ry.The mean shape coefficient was 0.339 on the windward side,-0.199 on the leeward side,and 0.538 for the tower frame.The modal frequency of the iron tower increased with modal order;the low-order modes showed overall bending,whereas the medium-and high-order modes showed mid-height buckling,and the iron tower exhibited a nonlinear response to environmental excitation.The results provide a theoretical basis for the wind-resistant protection of the Liaocheng Iron Tower and a useful reference for wind-load protection of similar ancient buildings.