三维超声风速计阴影补偿方法研究

Study on shadow compensation method for three-dimensional ultrasonic anemometer

三维风速计在众多领域有重要的价值,但三维超声风速计自身结构影响待测量风场,导致阴影效应的产生,从而引起测量误差。现有的阴影补偿方法研究多从阵列结构上优化或局限于二维风速风向,在应用到三维测风中效果较差。针对该问题,本文利用随机森林回归算法建立三维超声风速计阴影补偿方法,通过有限元仿真获取受阴影效应影响后的风速风向数据,以该数据为样本,对模型进行训练和测试。结果表明:本文提出的阴影补偿方法将风速值与理论值的相对误差降低到±1%以内,垂直风向角的平均相对误差从-4.1%降低至0.08%,水平风向角的平均相对误差从1.9%降低至-0.8%,验证了本文提出的补偿方法在解决阴影效应问题方面的可行性。

Three-dimensional anemometer plays important roles in many fields,but the structure of three-dimensional ultrasonic anemometers itself affects the wind field to be measured,which leads to shadow effect,resulting in measurement errors.Most of existing shadow compensation methods are optimized from array structure of the anemometers or limited to two-dimensional wind speed and direction,and the effect is poor when the methods are applied to three-dimensional wind measurement.Aiming at this problem,a shadow compensation method for three-dimensional ultrasonic anemometers is established by using random forest regression algorithm.The wind speed and wind direction data affected by shadow effect are obtained by finite element simulation.The model are trained and tested by taking the data as sample.Results show that the proposed shadow compensation method reduces the relative error of wind speed and theoretical value within±0.1%,reduces the average relative error of vertical wind angle from -4.1% to 0.08%,and reduces the average relative error of horizontal wind angle from 1.9% to -0.8%.It verifies the feasibility of the proposed method in solving the shadow effect problem.