针对近海复杂地形下海陆风对大气湍流特性的影响,在深圳市杨梅坑环境生态中心开展了大气湍流观测实验,利用温度脉动仪、超声风速仪和测风雷达获得了大气折射率结构常数、大气声虚温、风速风向廓线等时间序列数据。通过分析海陆风对大气湍流的功率谱、各向同性和湍流动能耗散率的影响发现,较陆风条件,湍流在海风条件下发展得更为充分。海风条件下各向同性系数接近甚至等于1的频率范围为0.05~50 Hz,速度功率谱幂率均接近-5/3;陆风条件下,只有0.8~10 Hz频率范围内的大气湍流在极短时段表现出局部各向同性,速度功率谱幂率均严重偏离-5/3且整体偏大,平均值在-1.3左右。海陆风条件下湍流动能耗散率与湍流强度呈线性关系,温度脉动仪和超声风速仪测得的数据拟合斜率分别为1.1、0.76和0.73、0.28。研究结论为深化海洋环境下的激光传输研究提供了一定的参考。

To grasp the influences of sea and land winds on the atmospheric turbulence characteristics in an offshore complex terrain, an atmospheric turbulence field experiment was implemented at Yangmeikeng Environmental Ecology Center in Shenzhen city. The data involved in atmospheric refractive index structure constant, atmospheric sound virtual temperature, wind profile are obtained by the micro-thermal meter, ultrasonic anemometer and Doppler lidar. By analyzing the effects from sea and land winds on the power spectrum, isotropy, and energy dissipation rate of turbulence, we find that the turbulence in sea winds develops more fully than in land winds. In the sea winds, the frequency range of isotropic coefficients close or equal to 1 spans 0.05-50 Hz, and the speed spectral power law is near -5/3. In land winds, the atmospheric turbulence only shows an isotropy at very small proportion of time at 0.8-10 Hz. The speed spectral power law seriously deviates from -5/3, tends to a high value, and possesses an average value of -1.3. Under the conditions of sea and land winds, the relationship between turbulence energy dissipation rate and turbulence intensity is linear. The fitting slopes of data from the micro-thermal meter are 1.1 and 0.76, and those from the ultrasonic anemometer are 0.73 and 0.28, respectively. The conclusion here can provide some reference for the study on laser transmission in a marine environment.