防护林地区近地面层湍流结构及通量特征研究

CHARACTERISTICS OF THE TURBULENCE STRUCTURE OF SURFACE IN THE WINDBREAK AREA

中文摘要:

      本文采用在大面积防护林地区近地面边界层中采集的湍流、辐射和廓线梯度资料,计算并分析了湍流结构及通量特征.结果表明:当-0.1<ξ<0.1范围内时,湍流动能,湍流强度随稳定度变化迅速;位温宏观量σ/θ_*服从σ_θ/θ_*=A(-ξ)^1/3规律,A=0.60;在湍流混合强烈时,林网内下层出现负潜热通量现象,并且林网上层潜热通量明显大于下层;湍流热通量则相反.本文还对计算湍流热通量和潜热通量的方法的适用性也做了比较,并且分别进行了误差分析.

英文摘要:

      In the paper,the atmospheric turbulence,the energy balance and the profile gradient data in windbreak area were analysed to study the characteristics of the windbreak area surface boundary layer turbulence sturcture and sensible heat flux and latent heat flux.The result shows that:(1) as -0.1<ξ<0.1 and 1.0-1,the turbulence kinetic energy,turbulence intensity changed fast by stability; (2) turbulence macroscopic quantity σ_θ/θ_*=A(-ξ)^1/3,where A=0.6;(3) the author has used the Bowen ratio method,the aerodynamic method and calculated sensible heat flux and latent heat flux over 14-16 m and 4-6 m in the windbreak and with compared.In this paper,the discusses of the errors from each method are also given.