Fibre optic flow monitor for multiple phase flows - contains fibre optical position filter acting as differential grid for flow contg. ferromagnetic impurities

摘要

The fibre optical flow monitor contains a fibre optical position filter operating as a differential grid by absorption and reflection to monitor the vol. flow via the flow speed. A predefined flow speed fed in as a desired value produces a narrow band signal whose centre frequency is proportional to the flow speed. Electronic frequency filters of high order consistt of high low and/or bandpass filters whose lower, upper or centre frequencies can be matched to the centre frequency corresp. to the required flow speed. The signal produced when the required speed is reached is prepared by conventional analogue electronic techniques to form display and control signals. USE/ADVANTAGE - For monitoring flow of multiple phase flows contg. different, dispersed, esp. including solid, ferromagnetic impurities. Hardware costs and measurement time are reduced by eliminating digitising of signals.