A Study On The Adaptability Of Multi-path Gas Ultrasonic Flow-meter

At present,the research direction of ultrasonic flow-meter is mainly focus on the second instrument,that increasing the instrument performance is mainly rely on handling signal by modern testing technology.But one of the important ultrasonic flow-meter characteristics that the sensitivity to convection field condition is neglected.So only detailed researching the flow characteristics of flow field can fundamentally meet the requirements of the high measuring accuracy of ultrasonic flow-meter and fully explore the meter performance potential.The foundation of this paper is the gas flow velocity differential method of ultrasonic flow-meter,study of the influence that the flow field factors and the install to the measuring error.through comprehensive analysis the distribution of flow speed and using CFD technology simulate convection field,it puts the optimizate scheme forward the adaptability of flow field,that the influence of different track layout and installation to measurement precision.Based on getting numerical and simulation the distribution of flow velocity,it derivates the error calculation formula of the single-path and multi-path gas ultrasonic flow-meter.This paper firstly analyzes the adaptability of different arrangements (point-blank type,diagonal type) in particular flow field;and then analyzes the adaptability of particular arrangement for the different channel flow fields (single bending tube,double bending pipe flow field).Through comparing the adaptability that arrangement of direct type and diagonal type to the flow field,it shows that diagonal type in single bent pipe has very good performance,and the diameter type of direct type installment performances better in dual bend pipe.the adaptability that Particular track layout mode (refraction type, parallel type) in bend pipe flow field shows:No matter in measuring precision and distribution, the performance that refraction type on the double bending pipe is more outstanding,and it can improve measurement accuracy by increasing the refraction;Parallel type has better performance ability in the simpler single bending pipe flow field,and that can improve the measurement precision by increasing the number of channels in the single bent pipe flow field.But increasing the number of channels in the double bent pipe flow field,the error is also getting subsequently greater.