紊流积分尺度实用识别算法及其数值验证.pdfVIP

学兔兔 第29卷 第4期 建筑科学与工程学报 Vo1．29 NO．4 2012年 12月 Journal 0f Architecture and Civil Engineering Dec．2012 文章编号：1 673—2049(2O12)04 0067 07 紊流积分尺度实用识别算法及其数值验证 王峰峰，赵 林 ， 曹曙阳，葛耀君 (同济大学 土木工程防灾国家重点实验室，上海 200092) 摘要：对比现有的几种紊流积分尺度算法，针对其在某些来流条件下存在的系统偏差，提出了基于 泰勒假定修正的紊流积分尺度识别算法。采用谐波合成法数值化地再现多组基于Von—Karman谱 的宽频紊流及窄带单频的风速时程序列，利用该算法对紊流积分尺度进行识别，并将识别结果与预 期理论值进行比较，提出基于时间尺度修正系数项的实用紊流积分尺度识别算法并进行了验证，得 出对于宽带紊流，时间尺度修正系数适合取为2／3，对于窄带紊流，时间尺度修正系数适合取为6。 结果表明：本文方法大大提高了紊流积分尺度的计算精度，具有很好的工程应用价值。 关键词：紊流积分尺度；泰勒假定；谐波合成法；识别算法 中图分类号：TU279．7 文献标志码：A Practical Recognition Algorithm of Turbulence Integral Scale and Its Numerical Validation WANG Feng—feng，ZHAO Lin，CAO Shu—yang，GE Yao—jun (State Key I aboratory for Disaster Reduction in Civil Engineering，Tongji University，Shanghai 200092， Abstract：Through the comparison of multiple algorithms of turbulence integral scale，the correctional recognition algorithm based on Taylor assumption was proposed．The harmonic synthesis method was used to generate several broadband time——series based on Von——Karman spectrum and several single—frequency time—series． Through the turbulence integral scale calculation of these signals using the correctional algorithm，the recognition results were compared with the expected theoretical values and the correctness of the algorithm was validated． The correction factor obtained for the broadband turbulence was 2／3．and for the narrowband turbulence was 6．The results show that this method greatly improves the calculation accuracy of the turbulence integral scale，which has a good value in engineering application． Key words：turbulence integral scale；Taylor assumption；harmonic synthesis method；re