Influence mechanism of temperature-induced zero drift on cryogenic Coriolis flow meters

Abstract

Coriolis flow meters are increasingly utilized in cryogenic liquid applications for precise mass flow rate measurement. However, zero drift, induced by significant temperature variations, compromises measurement stability and accuracy. Our work aims to establish a theoretical framework considering temperature variations to understand and mitigate zero drift in cryogenic conditions. The effects of driver offset, sensor offset, and asymmetry in mass, damping, and stiffness matrices at pipe nodes are analyzed across various structural models to assess the zero point. A computational method using finite element modeling is developed to correct thermal stresses and strains. Zero-drift values, reflecting zero-point responses to temperature changes, are calculated in the liquid nitrogen applications. Results reveal the impact of asymmetric structures on temperature-induced zero drift and identify variations in zero drift across different structural models. A correction method utilizing mean response values at multiple positions as coefficients is established, enabling quantitative correction and evaluation to mitigate zero drift.