Orifice plate meters are one of the most widely used technologies in industry for gas flow metering. This is due to their relative simplicity, the extensive publicly available data sets that led to several orifice plate meter standards [1, 2, 3, 4] and the fact that they are a relatively inexpensive method of gas metering. However, it is common in industry for gas meters to be installed in applications where the flows are actually wet gas flows, i.e. flows where there is some liquid entrainment in a predominantly gas flow. This is usually done out of economic necessity or due to the fact that the system designers were not aware at the systems conceptual design stage that the gas flow would have entrained liquid. Therefore, with the orifice plate meter being such a popular gas flow meter it is by default the most common wet gas flow meter.
The affect of wet gas flow on an orifice plate meter configured for gas flow service is complicated. There are on going research programs aimed at improving the understanding of the reaction of the orifice plate meter to wet gas flow. Whereas much of this research is published in recent conference papers it is very technical and is not always immediately relevant to the technician in the field how this information can be practically applied. This paper attempts to review the current scientific knowledge from a practical users stand point.