Clarification of Measurement Error of Orifice Flow Meter in Wet Steam Flow

Abstract

It is well known that the wetness of steam flow sometimes causes measurement errors of the steam flow meter. However, it is difficult to clarify a particular error quantitatively in actual plants and factories, and thus far, there has been no established method for estimating the error caused by the wetness of steam flow. Therefore, wet steam flow rate measurement experiments were conducted to clarify the measurement error caused by the wetness of steam flow in a plant and a factory. In this study, as the first step, the orifice flow meter was applied because it is the main flow meter in actual plants. Experiments were conducted with the steam flow apparatus by changing the flow rate, pressure and wetness. As a result, the correlation between the measurement error and the flow condition was clarified. Moreover, for the correction of the error, a new correction method was applied and was confirmed to be better than existing methods now being used.