Influence of the inlet nozzle diameter on the air gauge dynamics

Abstract

In the paper, the experimental results of the study on the dynamic characteristics of the air gauges are presented. Dynamical properties of the air gauge are dependent mainly on the pressure transducer type and also on the geometry of its flow-through elements. The present investigations focused on the diameter of the inlet nozzle and its impact on the time constant and the frequency at which the dynamic error would not exceed 5%. It was proved that in the most common configurations of the air gauges, those two parameters may vary up to 100%, and the dynamics of the air gauges worsened with smaller inlet nozzles. The results are of high practical importance in industrial measurement systems where the air gauges are applied, because the multiplication of the air gauge is typically set by the adjustment or replacement of the inlet nozzle.