Temperature and pressure compensation issues in vortex flowmeters
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Superheated steam has been measured using vortex flow meters. The design institute does not have formulas for temperature and pressure compensation, nor is there a design density value; only the vortex flow meter manufacturer provides a formula for density compensation. Is it possible to perform compensation for flow rate, temperature, and pressure? Is it possible to use the measured volumetric flow rate multiplied by the compensated density?
For vortex flowmeters used to measure steam, you can consult the manufacturer to have a flow integrator provided; this integrator includes parameters for temperature, pressure, and density. The accumulation of flow data can be done directly on the integrator, it can also be displayed on its digital display, or the data can be transmitted to a DCS system.
1. The first parameter measured by a vortex flow meter is the frequency of the vortices, which is converted into flow velocity; the volume flow rate is then calculated based on the pipe diameter. Therefore, vortex flow meters typically output the volume flow rate； 2. Steam is usually measured in terms of mass flow rate; to convert volume flow rate to mass flow rate, one option is to input a fixed density into the vortex flow meter for compensation ； II. Density compensation can be carried out within the DCS system using interpolation, based on the additional installed temperature and pressure values, to convert it into mass flow rate.
I have a question: Generally, gases such as oxygen are traded based on their volume. Therefore, the volumetric flow rate measured under actual operating conditions is adjusted by accounting for temperature and pressure effects to reflect standard conditions (20°C and 1 atmosphere), so as to facilitate trading and uniform settlement； And steam is generally billed based on mass, so to what standard condition is the temperature and pressure compensation for steam applied?