【摘要】 根据中国科学院兰州沙漠研究所室内沙风洞空洞条件下的气流场测定结果，阐述了风洞实验段内边界层发展、气流加速、底板边界层内的风速分布、自由流区风速不均匀性等规律，其中底板边界层内的风速分布遵循Ｃｏｌｅｓ定律和指数定律，不完全遵循普兰特－冯·卡曼对数定律。更多还原

【Abstract】 Flow field visualization test is one of important contents in wind tunnel experiment. Limited by similar conditions, the flow field measurement of modles about dunes or sand preventing engineerings may not be conducted under sand holding condition. So, there is most significance to proclaim flow field law under empty tunnel for programmes design and results calibration. The experiment is conducted in the famous indoor wind tunnel of Lanzhou Desert Research Institute. The total length of the tunnel is 37 78 m, in which that of working section is 16 23 m. Its cross section has 1 0 m width and 0 6 m height. Wind velocity can be regulated from 2 m/s to 40 m/s, and turbulency is less than 0 4% in the tunnel. There are five groups of wind velocity including 6 0,8 0,10 0,12 0 and 14 0 m/s are tested. Between the section of 3 3￣141 m, there are eight cross sections at 3 5,5 5,7 5,9 0,10 5,12 0,13 5 and 14 5 respectively. All sixty three measurement points distribute within the right part of cross sections and 0￣0 3 m over the bottom floor. The studing results prove that the isogram of wind velocity in whole cross sections looks like butterfly; the wind velocity distribution in boundary layer of bottom floor obeys exponent law, and the coefficient ( d ) of wind velocity increasing along the axis can be expressed as d=0 062x 0.431 ; the development of boundary layer over bottom floor follows a formula of δ=3 046x 0.676 . According to the study, it is suggested that experiment model should be located between 1 0 and 14 0 m in working section, and 0 1 m away from lateral wall of the tunnel; the testing wind velocity should be controlled within 20 m/s.更多还原