摘要
阐述了非Kolmogorov湍流谱理论以及湍流谱标度指数的测量与计算方法。在近地面多个地点对大气湍流温度起伏进行了多次的实验观测,结果表明:实际大气湍流温度谱标度指数多数不等于-5/3,并且通常在-2到-1之间变化。分析了湍流温度谱标度指数与湍流发展程度的相关性,利用小波分析方法展现了不同湍流强度下湍流温度脉动能量在各尺度之间的分配状态,发现湍流温度谱标度指数的绝对值在一定程度上随湍流强度的增加而增大。
The theory of non-Kolmogorov turbulence and the method to measure the scaling exponent of power spectrum are introduced. The experimental investigations of temperature fluctuation near the ground have been conducted in many places. The results show that most of the power spectrum exponents in real atmosphere are unequal to -- 5/3, and they always vary during the range of --2 and --1. The relativity of power spectrum exponent and the turbulence strength are analyzed. Meanwhile, distributions of power with scale at different turbulence strengths are also analyzed by the method of wavelet transform. As a result, the absolute value of temperature's power spectrum exponent to some extent has the tendency of increasing with the increment of tur- bulence strength.
出处
《强激光与粒子束》
EI
CAS
CSCD
北大核心
2006年第9期1423-1427,共5页
High Power Laser and Particle Beams
基金
国家863计划项目资助课题
国家自然科学基金资助课题(40475010)