利用自然低温的旋转叶片结冰风洞试验系统设计

摘要

为开展风力机旋转叶片结冰风洞试验研究,设计了一种利用寒冷地区自然低温环境的具有可变截面试验段的结冰风洞试验系统.该系统在原有常规结冰风洞的基础上改进了试验段,设置了喷雾区与非喷雾区,风力机叶片实验台可设置在非喷雾区内,而旋转叶片在转至喷雾区时进行结冰测试.为测试该系统的各项参数以及研究系统的可行性,对该试验系统的3个主要环境变量:试验段速度分布、温度分布和液态水含量分布进行了测试和标定.在此基础上,进行了绕轴旋转圆柱和叶片段的结冰试验,对2个系统下的无因次结冰面积及结冰形状进行了对比分析.结果显示该系统各项参数稳定,利用2个系统得到的结冰形状相似度高,结冰面积一致性较好,表明该系统可用于进行旋转机械结冰风洞试验研究.%In order to carry out the study on icing wind tunnel experiment for rotating blades of wind turbine,an icing wind tunnel test system with variable cross test sections by using nature low temperature in cold region was designed.Based on the original wind tunnel in the lab,the test section was reformed by adding a non-spry section.Therefore,the test station for the rotating blade of the wind turbine can be set in the non-spry section and the icing test can be finished in the water spry section.The diameter of the wind turbine rotor is not limited by the water spry section size by using this test system.To measure the main parameters and verify the test ability of this system,three main icing parameters of the test section including wind speed,temperature and liquid water content distributions were tested and analyzed.Furthermore,icing experiments on rotating cylinder and rotating blade airfoil were carried out.The test results including the icing shape and the dimensionless icing area are discussed by comparing with the author's previous results of the original icing wind tunnel tests.According to the test results,the distributions of the main parameters of the test section are stable.The icing shape on cylinders and blade airfoils obtained by both test systems agrees in some degree and the values of the dimensionless icing areas are close.The result shows that the new icing wind tunnel system can be used for the research on icing issue for rotating machinery.