Flow field analysis of the measuring stability of the head of a pneumatic measuring instrument. (12th August 2022) - Wei, Long
Based on the principle of pneumatic measuring instruments, it is found that the edge of the exhaust groove near the end face of the nozzle will produce a local high-pressure zone, which will lead to the increase of the gas resistance and affect the measurement accuracy. Therefore, the uniformity of the gas film flow field is the key factor for the determination of measurement stability. Based on this, a double-E exhaust groove structure probe is designed and presented. The results demonstrate that the pressure distribution and flow field distribution between the large hole of a connecting rod and a probe with a double-E exhaust groove structure are more uniform; the measured fluctuation amplitude is 20% that of the existing probe, thereby demonstrating an effective improvement of the measurement accuracy and stability of the pneumatic gauge. [Submitted 4 April 2020; Accepted 5 August 2020]