中文摘要：

为了研究树冠对其周围温度场的影响,对真实树冠进行了二维简化并提出分形维数（D）、稠密度（SVF）以及叶面积指数（LAI）等相关结构参数.采用计算流体动力学（CFD）方法对树冠内部结构参数与其周围温度场关系进行数值模拟与分析.通过数值模拟与试验测量相结合,讨论了树冠形态结构参数对树冠周围（主要是树冠后部）温度的影响规律.通过对数值模拟计算结果进行回归分析,给出树冠温度分布与结构参数的关系式.研究结果表明：试验数据与模拟公式计算值基本吻合,只有在叶面积指数过大的极端状态下出现较大偏差,二者在变化趋势上表现出较好的一致性;树冠周围温度与迎面风速成反比,与叶面积指数之间的关系则较为复杂.

英文摘要：

In order to study the influence of the crowns on the temperature field around trees,the simplified two-dimensional geometric model of canopy and corresponding parameters including fractal dimension（D）,density（SVF）and leaf area index（LAI）,.i e.are used in CFD（computational fluid dynamics）simulation and experimental measurement.The effects of the canopy morphological structural parameters on the temperature field behind the tree are discussed.Through regression analysis with the results of numerical simulation,the equation of the relation between temperature distribution inside the crown and the structural parameters is given.The experimental results show that the test data agrees well with the simulated data,moreover,it has good consistency in the changing trends until the leaf area index is extreme large.The temperature around the canopy decreases with the increase of the wind speed,but the relationship with the leaf area index is complex.