Elbow Flow Meters : Effects of Wall Curvature Inaccuracies on Discharge Coefficients

Abstract

Effects of wall curvature inaccuracies on discharge coefficients of elbow flow meters are examined theoretically and experimentally. The flow is analyzed mathematically for a two-dimensional potential flow and the result is confirmed by experiments. If a commercial elbow is used as a flow meter, the error in the discharge coefficients resulting from the inaccuracies of curvature may be assumed to reach about 5 percent. Thus it can be elucidated that at least a part of scattering in the discharge coefficients appearing in the past investigations should be attributable to the wall curvature inaccuracies of elbows used.