Calibration of the Fiberoptical One-Point Flow Meter Characterized by Spatial Filtering

Using a gravitational flow measuring system with an uncertainty ≤5·10^–4 as a primary standard the accuracy of a fiberoptical flow meter characterized by spatial filtering was determinated to 5,5·10^–3. The rod shaped measuring probe was positioned in a water pipe flow DN 100 with the optical measuring volume on the pipe axis. Volume flow was calculated by using given velocity profiles.