Ultrasonic flow meters require fully developed flow conditions to ensure the meter will perform as specified. There are two basic types of measuring principles, Doppler and Transit Time. Both do require adhering to basic installation guidelines to minimize errors caused by flow profile disturbances. However, these requirements vary by manufacturer, which could lead to some confusion; we have seen recommendations as low as 10 straight pipe runs upstream and 5 straight pipe runs downstream.
A piping system that contains lengths of straight pipe such as those described in below Table. The optimum straight pipe diameter recommendations apply to pipes in both horizontal and vertical orientation. The straight runs in Table apply to liquid velocities that are nominally 7 FPS [2.2 MPS]. As liquid velocity increases above this nominal rate, the requirement for straight pipe increases proportionally.
Post time: Oct-14-2021