Characterization of a standard pneumatic piston gauge using finite element simulation technique vs cross-float, theoretical and Monte Carlo approaches

Abstract

Simulation techniques when applied for metrological estimations have recently emerged as a tool for potential improvement in design and performance aspects. The current paper reports one such application for the numerical estimation of the distortions and strains developed in a standard piston gauge leading to the estimation of the effective area and the pressure distortion coefficient up to a pressure of 4 MPa, through the application of finite element analysis (FEA) technique and a comparative analysis of its outcome with the experimentally and theoretically determined values as well as the Monte-Carlo simulation results. The experimental characterization was done using cross-floating method while theoretical approach used the Dadson's equations. The strain values for the piston-cylinder assembly under pressure, obtained from the FEA simulation, were used to calculate the distortions in the piston and cylinder, which in turn were used for calculating the effective area of the piston gauge at various pressure points. From the obtained effective area with pressure values, the zero pressure effective area and the distortion coefficients were calculated. In addition, the results of FEA were also compared with the previously published results from the Monte Carlo Simulation on the same piston-cylinder assembly. Interestingly, the uncertainty associated with the distortion coefficient estimated using FEA, was found to be an order of magnitude lower as compared to the other approaches.