基于三维扫描技术的结冰风洞冰形非接触测量研究

Non-contact measurement of ice shape in icing wind tunnel based on 3D scanning technology

在结冰风洞中进行冰形测量,传统的接触方法测量精度低、对冰形有损坏,且只能获得二维的冰形迹线。采用双目视觉测量与结构光方法相结合的三维扫描技术,利用两个CCD相机和一个光栅投射器,辅助旋转平台和计算机,构成一个三维非接触扫描系统。通过解决冰的透光性以及结冰风洞低温高湿的环境影响,设计加热保温装置,并探索多种显影剂及播撒方法,实现对透明光冰的非接触测量。实验结果表明:采用三维扫描系统测量冰形的精度可达到0.1 mm,可以满足小尺度模型结冰外形的三维非接触测量,可在实验研究或工程实践中使用。

Because of the shortcoming of the traditional contact measurement of ice shape in icing wind tunnel,such as low accuracy, damage to the ice shape and only obtaining 2 D ice shape trajectory. A 3 D scanning technology was developed by combining binocular vision measurement and structured light method, which includes two CCD cameras, a grating projector, an auxiliary rotating platform and a computer, forming a 3 D non-contact scanning system. Ice transparence and environment influence of icing wind tunnel with low temperature and high humidity were considered, and an attemperator was designed and many types of developers and seeding methods were researched to achieve non-contact measurement for light ice with transparent characteristics. The test results indicate that ice shape measuring precision based on 3 D scanning system was 0.1 mm, which meets 3 D non-contact measurement demands for small-size model icing shape and it can be used during experimental study or engineering practice.