Velocity profile measurements under flield conditional for identification of the cause of orifice metering errors

摘要

Research has shown that distorted velocity profiles cause measurement errors at orifice meters. An unusual velocity profile related metering error was identified in tests with high pressure natural gas using a 250 mm (10 inch) orifice fitting. Flow measurements between the two sides of the orifice fitting differed by as much as 0.6 percent. Velocity profiles were measured using carefully selected flow probes and methods.