Measurement of powder volume fraction in pipe flow using ultrasound

doi:10.7523/j.issn.2095-6134.2016.02.021

Abstract

Abstract:

The transportation of gas-solid particle powder in pipeline widely exists in the manufacturing processes of chemical engineering, food processing, electric power, metallurgy, pharmacy, and other industries. With the help of on-line measurement of key parameters of powder speed, concentration, particle size, etc., the optimized control process can be implemented to improve production efficiency and product quality and reduce energy consumption. Based on the scattering model in ultrasonic propagation theory, numerical simulation has been carried out and a fitting of data shows that the ultrasonic attenuation and velocity present linear functions of the volume fraction at each frequency. An integrated ultrasonic probe with frequency of 30 kHz was designed, and then an experiment was conducted to measure the concentration of pneumatically conveyed cement raw meal powder in a bend pipeline at a cement plant in Hangzhou. The powder concentration distribution in the pipe along the direction of pipe diameter was obtained by using the methods of ultrasonic attenuation and ultrasound velocity, respectively.

Key words: ultrasound, powder, volume fraction, measurement

CLC Number:

O359

LI Yongming, SU Mingxu, YUAN Anli, CAI Xiaosu. Measurement of powder volume fraction in pipe flow using ultrasound[J]. , 2016, 33(2): 277-282.

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