Correction of Wet Gas Flow Measurements Applying Standard Orifice

Correction of Wet Gas Flow Measurements Applying Standard Orifice

Barbara Tomaszewska-Wach Mariusz Rzasa

Opole University of Technology, Faculty of Mechanical Engineering

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Differential pressure measurements are commonly applied in industrial conditions, due to the fact that measurements that apply them are simple and offer relatively high accuracy. In gas installations, the liquid is often condensed in the form of a droplet present in the gas. When the liquid is transported along with gas, this leads to a significant increase in the differential pressure and incorrect indications of measuring equipment. In addition, the presence of the liquid phase in the flow leads to interference and pressure pulsations. This article reports the results of a study concerned with finding a solution that can offer a way to correct the over-reading of the measured gas flow rate depending on the mass fraction of the liquid in it. The standard orifice was subjected to an experimental study, and then on the basis of this analysis, an algorithm for a computer over-reading model was developed. The experiment involved the measurement of airflow with a small amount of dispersed water in the form of droplets. The results were compared with other correction methods familiar from the literature.


air–water flow, experimental research, over-reading, standard orifice, two-phase flow, wet gas


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