The distribution of flow field of air duct in circulating fluidized bed(CFB) boiler is very complicated

which makes it difficult to accurately measure the air volume. By using the fan performance measurement method based on thermodynamic principle

this paper develops a new type real-time fan performance measuring instrument suitable for CFB boilers. A total of 4 sets of real-time measuring instruments for fan performance were installed on 2 primary fans and 2 secondary fans of Unit 2 of a 330 MW CFB boiler in a power plant. The accuracy of the meters was verified through experiments. The results show that

the distributed control system(DCS) of the power plant showed that the primary fan outlet air volume differed from the measured value on-site by-29.48%

while the relative deviation of the measured value of the new-type fan performance real-time monitoring instrument was only + 0.6%. The DCS showed the secondary fan outlet air volume differed from the measured value on-site by-11.90%

while the relative deviation of the measured value of the new-type fan performance real-time monitoring instrument was only-2.2%. The meter also has the characteristics of simple structure

easy installation

and real-time measurement of fan efficiency. It overcomes the technical problem of inaccurate air flow measurement of conventional CFB boilers

and has great market potential.