抄録
A study on the characterization of a controlled-clearance piston gauge was performed. In this study, the Heydemann-Welch model was used to define the controlled-clearance piston gauge as a primary pressure gauge. The parameters needed for the model were determined from the measurements, and the characteristics of the controlled-clearance gauge were evaluated. The results obtained are as follows: (1) The best jacket pressure function to keep the clearance between the piston and cylinder constant was determined from the measurement. (2) The dimensional clearance between the piston and cylinder was estimated. (3) The uncertainty of the effective area of the piston-cylinder used for the gauge was evaluated by the function of the system and jacket pressures.
