中文摘要：

采用数值计算软件FLUENT研究障碍物的尺寸、障碍物与山坡坡底的距离对山丘风场的影响.根据计算结果绘制山顶上方50m处的湍流强度和速度变化图,山丘表面风速值线图以及来流方向分风速等值线图.分析结果表明：障碍物越高,距离山坡坡底越近,山顶风速减小幅度越大,越不稳定;山丘上游存在障碍物时,迎风坡和背风坡均出现低速区;障碍物距离山坡坡底较近时,迎风面上还出现了回流现象.迎风面、背风面的速度变化较大,不适合安装风力机;山丘两侧风速一直变化不大,比较适合安装风力机.

英文摘要：

The influence of the size of the obstacles and their distance from hill slope bottom on hill wind field is investigated with the FLUENT software for numerical calculation. According to the calculation re- sults, turbulence intensity and velocity variation profiles at 50 m above the hill top, wind speed curve at hill surface, and isolines of onflow component of wind speed are drawn. It is shown by the result of com- putation that the higher the obstacle the shorter the distance from slope bottom, the larger the decreasing amplitude of wind speed at hilltop would be, and the more unstable of the wind speed, would be, also. When there is obstacle upwind at the hill, the low-wind areas would take place at the slopes upwind and downwind and the backflow would occur upwind at the slope if the obstacle was closer to slope bottom. Wind speed changes larger both up-and downwind at the slope and there fore is inappropriate to instal wind turbines there. At both sides of the hill, however, the wind speed does not change much, so that is appro- priate to instal wind turbines.