风电机组风洞测试的阻塞效应分析

风洞测试具有方便、快捷和高效的优势,在风电机组输出功率特性测试中应用较多。测试风轮直径较大时,由于存在风洞堵塞效应,会对测试结果造成影响。以300 W风电机组作为研究对象,分别采用风洞测试和车载测试进行输出功率特性测试。测试过程采用负载法,分别以电阻和蓄电池作为负载进行测试。在风洞截面为3m×3m的试验段中测试,机组空载启动风速为4.3m/s~4.8m/s,以电阻为负载时的额定风速为6.2 m/s;在车载测试中,机组空载启动风速为5.7m/s~6.2m/s,以电阻为负载时的额定风速为8.1 m/s。风洞测试比车载测试的启动风速低1.4 m/s,占车载测试启动风速的24.6 %,比车载测试额定风速低1.9 m/s,占车载测试额定风速的23.5 %。风轮直径2.3 m,其扫掠面积占风洞试验段截面面积的46.2 %,风洞的堵塞效应较大,致风洞测试数据与车载测试数据相差较大,因此风洞测试后需要修正。

Analysis of Clogging Effect in Wind Tunnel Test of Wind Turbine

Wind tunnel test has the advantages of convenience, speed and efficiency, and is widely used in wind turbine power characteristics test. When the diameter of the test rotor is large, the test results will be affected by the clogging effect of wind tunnel. The 300W wind turbine was used as the research object, and the output power characteristics test was performed using the wind tunnel test and the vehicle test respectively. The test process used a load method with resistance and the battery as the load. The test was carried out in a test segment with a wind tunnel section of 3m×3m. The no-load starting wind speed of wind turbine is 4.3m/s~4.8m/s. The rated wind speed when the resistance is the load is 6.2 m/s. In the vehicle test, the wind turbine"s no-load starting wind speed is 5.7m/s~6.2m/s, and the rated wind speed when the resistance is the load is 8.1 m/s. The starting wind speed of the wind tunnel test is 1.4m/s lower than that of the vehicle test, accounting for 24.6% of the starting wind speed of the vehicle test, and the rated wind speed of the wind tunnel test is 1.9m/s lower than that of the vehicle test, accounting for 23.5% of the rated wind speed of the vehicle test. The diameter of the rotor is 2.3m,and its swept area accounts for 46.2% of the cross-sectional area of the wind tunnel test section. The clogging effect of the wind tunnel is large, which results in a large difference between the wind tunnel test data and the vehicle test data. so it needs to be corrected after the wind tunnel test.