COMPREHENSIVE SURVEY ON THE EFFECTS OF WATER AND GREEN IN THE FORMATION OF URBAN THERMAL ENVIRONMENT

对夏季水和绿色在城市热环境形成中的作用进行了综合调查，主要结果如下：（1）通过对风向、风速和气温的长期观测，评价了海风的降温作用。陆风向海风的转换使气温下降或气温上升减缓。它对降低气温的平均影响是3摄氏度，但根据离海的距离而不同。(2)对河流和街道的热环境进行了多点测量。测量表明，这条河是风的通道，它的表面温度最高比街道上的温度低30摄氏度。因此，在海风时间，河上的空气温度比街道上的空气温度最多低4摄氏度。然而，这种影响根据与大海的距离而不同。(3)温度分布 ...更多信息 在一个大池塘周围，测量了水满的时候和排干的时候。池塘及其附近形成低温区。池塘使其外围200- 400米区域的气温降低约0.5摄氏度。池塘的冷却作用在背风面比迎风面更明显。（4）对公园内、外绿色的热环境进行了测量。公园内的绿色上的空气温度最多比周围街道上的空气温度低3.5摄氏度。植被景观因子和叶景观因子大的地区，气温有变低的趋势。(5)城市风场的数值模拟显示了预测城市热环境的可能性。模拟采用二维大涡模拟和k-ε两方程模式。边界条件为地面温度分布和由粗糙度参数计算的风廓线。(6)城市大气边界层温度场的数值模拟结果与实测值吻合较好。模拟采用一维地表热平衡方程，考虑了建筑物的形态和分布。该模拟方法通过对建筑物高度、人为热、水面覆盖率和绿色覆盖率等参数的敏感性分析，对城市热环境进行定量预测。少

Comprehensive surveys on the effects of water and green in the formation of urban thermal environment in summer were carried out and their main results are as follows: (1) Long-term observation of wind direction, wind speed and air temperature was carried out to evaluate the cooling effect of sea breeze. The sift from land breeze to sea breeze causes lowering of air temperature or mitigation of air temperature rising. Its average effect on the lowering of air temperature is 3ﾟC but is different according to the distance from the sea. (2) Multi-point measurements were carried out to compare the thermal environment on a river and streets. The measurements show the river is a passing way of wind and its surface temperature is lower than that on streets by 30ﾟC in maximum. Therefore, the air temperature on the river in sea breeze time is lower than that on the streets by 4ﾟC in maximum. The effect, however, is different according to the distance from the sea. (3) Temperature distributions … More around a large pond were measured when the water was full and when it was drained. Low temperature area is formed on the pond and its vicinity. The pond lowers the air temperature in its outer 200-400m area about 0.5ﾟC. The cooling effect of the pond appears more widely in its leeward area than in windward area (4) Thermal environments in and out of green in parks were measured. The air temperature on green in a park is lower than that on its surrounding streets by 3.5ﾟC in maximum. The area where the view factor of vegetation and that of foliage are large has a tendency that there air temperature becomes low. (5) Numerical simulations of urban wind showed the possibility of predicting urban thermal environment. The simulations were two dimension using Large Eddy Simulation and k-epsilon two equation model. Their boundary condition was the temperature distribution at ground surface and the wind profile calculated by roughness parameters. (6) The temperature distribution predicted by numerical simulations for urban atmospheric boundary layer accorded with measured values. The simulation used single dimensional heat balance equation at ground surface and considered the configuration and distribution of buildings. This simulation method was used for quantitative prediction of urban thermal environment through parameter sensitivity analysis; the changed parameters are the height of buildings, anthropogenic heat, surface covering ratio of water and green. Less