Finite element analysis methods were developed and applied to gas piston-cylinder units (PCUs) of piston- and cylinder-floating configuration (2, 5, 10 and 20) cm2 nominal effective area, operated in gauge and absolute mode at pressures (0.06-7.5) MPa to determine their zero pressure and pressure-dependent effective areas, as well as pressure distortion coefficients (λ) with associated uncertainties. Real dimensional properties of the PCUs were used. λ were found to be independent of gas (ideal, N2, He) within the viscous flow model, but strongly dependent on the gap shape, operation mode and elastic properties. Results demonstrate good agreement for λ, with its uncertainty for different PCUs varying between (0.03 and 0.21) × 10-6 MPa-1 corresponding to maximum relative uncertainties in pressure of (0.07-0.34) × 10-6.
FEA calculation of pressure distortion coefficients of gas-operated pressure balances - EURAMET project 1039
GIOVINCO, Gaspare;
2012-01-01
Abstract
Finite element analysis methods were developed and applied to gas piston-cylinder units (PCUs) of piston- and cylinder-floating configuration (2, 5, 10 and 20) cm2 nominal effective area, operated in gauge and absolute mode at pressures (0.06-7.5) MPa to determine their zero pressure and pressure-dependent effective areas, as well as pressure distortion coefficients (λ) with associated uncertainties. Real dimensional properties of the PCUs were used. λ were found to be independent of gas (ideal, N2, He) within the viscous flow model, but strongly dependent on the gap shape, operation mode and elastic properties. Results demonstrate good agreement for λ, with its uncertainty for different PCUs varying between (0.03 and 0.21) × 10-6 MPa-1 corresponding to maximum relative uncertainties in pressure of (0.07-0.34) × 10-6.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
