The Ω-shaped Coriolis flowmeter, owing to its suitability for high-pressure and
wide-temperature conditions, has become the preferred device for CO2
metering in CCUS-EOR projects. In practical applications, however, the volatile
nature of operating pressures and temperatures triggers a persistent zero-point
drift. This instability creates a ripple effect: it not only degrades metering
precision but also fundamentally undermines the equitable basis of carbon
trading markets. This study, through theoretical analysis, fluid-structure
coupling simulation, and experiments, deeply investigates the patterns of
zero-point drift in Ω-shaped Coriolis flowmeters and corresponding correction
methods. The research reveals that the asymmetry of the measuring tube structure
is the primary cause of zero-point drift, with changes in the vibration
frequency of the measuring tube directly influencing the zero-point value,
leading to the establishment of a related zero-point drift model. Based on the
asymmetric structure of a DN15 Ω-shaped Coriolis flowmeter, simulations were
performed to model the zero-point variation patterns under different pressures
and temperatures using CO2 as the fluid, thereby verifying the
effectiveness of the zero-point drift model. To validate our approach, we
executed targeted zero-point experiments, employing the proposed model to
predict zero-point shifts across a broad spectrum of pressures and temperatures.
By integrating these predictions into a refined correction framework, we
successfully neutralized drift-induced errors. These findings offer both a
robust theoretical pillar and a practical toolkit for high-precision
CO2 accounting, ultimately safeguarding the economic integrity of
carbon trading within CCUS-EOR initiatives.