Optical flow rate measureemtn technologies in germany and russia

摘要

Gas flow metering of large flowrates is a challenge especially if high precision is requreid.A lot of conventional techniques have been developed during hte past and due to the rapid development of new optoelectronic devices in recent years,optical techniuqes like laser-Doppler anemonmetry (LDA) have now been developed so far that they can be sued as primary standards and industrial meters as well.At PTB in Germany the LDA-technique is used as a primary standard for the direct measurement of large flow rates of gases (air) up to 5.500 cubicmeters per hour,and a lot of efforts have been made to develop a single point measuring LDA precise flow monitoring and industrial applciation.especially in russia a variety of excellent optical flowmeters for liquids for medium flowrates have bene successfully developed.All these techniques have a great inherential potential for use in natural gases at high pressures as it was shown in first experiments.