Static Characteristics of the Air Gauging Sensor Applied in the Microhole Measurement

Microhole measurement methods struggle to produce the intended results because of poor in situ measurement circumstances. The back-pressure air gauge, which is self-clean and unaffected by complicated environments, can be equipped with a microprobe to obtain desired results, but the limited application of the sensor is caused by its expensive cost and challenging processing requirements. In this article, an air gauging sensor without a microprobe was presented as a low-cost and simple structure solution to the above issue and the static characteristics were optimized in several methods accounting for different microhole diameters. Theoretical and experimental static characteristics were obtained using the steady-state model and experimental data. Then, the effects of crucial parameters on static characteristics, including the feeding pressure and the inlet nozzle diameter, were analyzed under various settings. A novel performance improvement method of the sensor was presented by comparing and analyzing the
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