利用红外辐射获取金属覆层下表面的通道信息

Information Acquisition of Internal Channels of Metal Using Infrared Camera

介绍了一种利用红外热像仪获取金属覆层下表面微小通道分布及通塞信息的方法——冷热交替喷流法。该方法的实质是将冷热水以脉冲形式交替通入金属覆层下通道,大幅提升通道与试件其他部位的温差,通过热像仪将该温差信息转化为红外图像,进而表征出通道的分布及通塞等相关信息。实验结果表明:用冷、热水交替可有效提高通道温差,热水通入通道实现金属试件的整体加热,再由冷水快速降低通道温度,进而提高热辐射图像对比度;通过热辐射图像对比发现,特定采集方式明显优于连续采集方式,特定采集方式中图像质量与热像仪开始采集图像的时刻紧密相关。该方法对发动机叶片内部冷却通道的堵塞情况检测有重要研究价值。

A method is proposed for acquesting distributing and blocking information of tittle internal channels of metal by using infrared camera. The matter of this method is that hot and cold water are pressed into channels alternately lasting for a pulse, then the temperature differences between channels and metal are increased greatly. It is easy to change the temperature differences into infrared image through infrared camera, and the distributing and blocking information of tittle channels can be acquested. The experiment result shows that using hot and cold water alternately can increase temperature differences efficiently, metal is heated up whole when hot water is pressed into channels, then cooled down rapidly by pressing in cold water, so that the contrast degree of thermal images is improved. Special way is superior to continuity way, the image quality is correlate to the time when it begins to take pictures closely. This method has important research value to check whether internal cooling channels of turbine blades are blocked or not.