Pressure fluctuations measurement system for flowing fluids has laser beam passing through cell with window at either side, forming part of laser Doppler-interferometer

摘要

The pressure fluctuations measurement system (11) consists of a laser Doppler-interferometer. A laser (20) generates a coherent beam of light (2) passing through a cell with parallel entrance (8) and exit (9) windows, filled with a fluid (1) subject to pressure fluctuations. The laser beam falls on a photocell (3). The laser and the photocell are connected to an evaluation circuit (5) a reference sensor (6) and may be connected to an actuator (7).