ASME MFC-10M pdf download METHOD FOR ESTABLISHING INSTALLATION EFFECTS ON FLOWMETERS
(c) The tests outlined in this Standard should cover the pertinent range of fluid flow rates, Reynolds num- bers, etc., of the meter to be evaluated. NOTE: This requirement can be satisfied by stating the range of pertinent nondimensionalized parameters over which the data were obtained (see Section 7). (d) To avoid missing periodic spatial flow variations, measurements should be made at pipe lengths that are not integer multiples of each other.
(e) All calibrations should be performed at the same flow conditions or as close as practical to the same conditions when comparing different test runs. When reducing data, corrections can be made via an indepen- dent parameter such as Reynolds number when it can be shown that the overall effects of the different fluid conditions (temperature, pressure, etc.) and/or the fluid properties (density, viscosity, etc.) on the tested flowmeter size and type are known and have been ac- counted for. (f) All raw calibration data should be recorded and retained.
5 STANDARD REFERENCE CONDITIONS
5.1 Description The process of establishing installation effects in- volves the comparison of the performance to that ob- tained in a standard reference condition. This document allows for two standard reference conditions. One is based on having specific, well-defined flow patterns in the test installation (Basic Reference Condition), and the other is based on the constancy of flowmeter performance along the pipe (Working Reference Con- dition).
5.1.1 Basic Reference Condition. The Basic Ref- erence Condition exists when the fluid velocity pattern at the flowmeter is identical to that which would exist if the meter were installed in a conduit running full and steady with unlimited lengths of straight upstream and downstream pipe. Such a flow pattern is character- ized by zero time-averaged radial and azimuthal fluid velocity components and an axisymmetric axial velocity profile that is independent of axial position. These components can be considered to be zero if their average values are zero to within the measurement uncertainty or if they are negligible to within 0.01% of the average flow velocity. The exact axial velocity profile depends on the inner wall roughness of the pipe (see ASME B46.1-1985) and the Reynolds number of the flow. The above flow pattern which defines the Basic Reference Condition is often described as one which is steady, free from swirl, and having a fully-developed axial velocity profile.