Fabrication and performance evaluation of micro-channels in aircraft wind-tunnel-models for pressure measurements using stereolithography

In order to overcome the difficulties with machining the internal channels of a wind tunnel aircraft model for pressure measurements, this paper proposes the use of stereolithography to realize the integrated forming of aerodynamic configurations and internal channels. A series of micro-channels with different diameters and lengths are fabricated, and their forming qualities are examined with an optical microscope system. The diameters of cross-sections are also measured to conform with the radius compensation principle concerning the parameters such as diameter, length and prototyping direction. Air tightness and air permeability of the micro-channels is verified by means of a special test device. Therefore, the channels based on stereolithography meet the requirements of wind tunnel test and they are able to replace the metal tubes.