近地边界层脉动风数值模拟

在研究以往脉动风时程模拟方法的基础上,采用非均匀圆频率间隔的方法,改进以往谐波合成法模拟的周期性缺点.改进前后2种方法的对比表明,在时程曲线方面,原有方法显示的明显周期在改进方法中已经较难发现;在自功率谱方面,改进方法以较小的波动更加贴合目标曲线,提高了模拟精度.对改进方法与实测数据在功率谱、方差和湍流强度等相关参数方面进行了比较,相差均较小.这说明了该改进数值模拟方法的可行性和有效性.

The Numerical Simulation of Fluctuation Wind in the Surface Boundary Layer

Based on the research of the previous fluctuating wind speed time series simulation methods, an improved method was used with non-uniform circular frequency interval to improve the periodic defect of harmony-superposition method. Through the comparison of two methods, in the time-area curve, period obviously in the previous method is already hard to find out in the improved method; in the power spectrum, the new method with smaller fluctuations is more suitable with the target curve, illustrating the improvement of simulation accuracy. Through the comparison of the power spectrum, variance and the turbulence intensity between the improved method and the measured data, the errors are very small.These show that the improved numerical simulation method is feasible and effective.