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从流体力学的基本公式出发,获得了结构受流场作用的非定常气动力公式。在积分降阶时,采用奥高公式使得非定常气动力公式不仅能够适用于单箱桥梁断面周围的流场,也能够适用于多箱分离断面周围的多连通流场。同时,由于试验流场数据的采样频率较低,因此给出了仅忽略时间项的简化公式以及忽略时间并仅依照有限区域流场进行计算的简化公式。采用数值模拟和粒子图像测速系统(PIV)获得了雷诺数为22000的方柱绕流的流场,由于能够与其他研究者的结果得到较好的吻合,因此取其流场数据用于验证上述气动力公式。结果表明,按照该文推导得到的气动力公式计算,得到的阻力系数的计算结果较好,而升力系数结果则存在一定的差别。采用简化公式计算时,仅忽略时间项的简化公式得到的结果较好,而更进一步的简化公式则差别较大。该文还以分离双箱断面周围的数值模拟流场为例进行了公式的验证,结果依然是阻力系数较好,而升力系数存在一定的差距。最后对于阻力系数和升力系数验证计算结果出现的这种差异进行了分析。
Based on the basic formulas of fluid mechanics, we obtain the unsteady aerodynamic formula of structure affected by the flow field. In order to reduce the integral, the Arcgap formula can make the unsteady aerodynamic equation not only applicable to the flow field around the single box bridge section but also to the multi-connected flow field around the multi-box separation section. At the same time, due to the low sampling frequency of the experimental flow field data, a simplified formula that ignores only the time term and a simplified formula that ignores time and calculates only in the limited area flow field are given. The numerical simulation and Particle Image Velocimetry (PIV) system were used to obtain the flow field around a rectangular column with a Reynolds number of 22000. The flow field obtained from the other researchers was used to verify the above Pneumatic formula. The results show that according to the aerodynamic formula derived from this paper, the calculated resistance coefficient is good, but the lift coefficient has some differences. When using the simplified formula, the simplified formula that ignores only the time item gives better results, while the further simplified formulas are quite different. In this paper, the numerical simulation of the flow field around the cross-section of the double box is also taken as an example to verify the formula. The result is still that the drag coefficient is good and the lift coefficient has a certain gap. Finally, this difference between the calculation results of the resistance coefficient and the lift coefficient is analyzed.