Numerical Simulation Study on Characteristics and Prevention Methods of Ash Deposition in Thermal Power Units Flue

doi:10.3969/j.issn.1008-0198.2025.02.008

Abstract

Abstract: In order to solve the problem of ash deposition in the flue caused by deep peak loading regulation of thermal power units, based on the numerical simulation method of Fluent, the characteristics of fly ash deposition and particle distribution in the flue under different load conditions of thermal power units are studied by constructing a geometric model of the flue structure and a mathematical model of its internal flow. A method to prevent ash deposition in the flue is put forward based on the practical experience of engineering, which is to install a baffle and a high-speed jet nozzle in the flue. The simulation results show that fly ash begins to deposit in the flue when the load of the unit is lower than 80%, and a large number of fly ash deposits in the flue when the load is lower than 40%. The pattern of fly ash particle deposition in different flue structures is as follows: T-shaped flue>right-angle elbow>horizontal flue>gradual flue. And more than 90% of the deposited fly ash particles are larger than 34 μm in diameter. Compared with the existing flue, the flue equipped with the baffle or jet nozzle can reduce the fly ash deposition by 29.16%~58.62% when the unit is operating at 40% of the rated load.

Key words: flue, ash deposition characteristics, numerical simulation, ash deposition prevention

CLC Number:

TK227.3

YAN Youyang, CHEN Donglin, YANG Zhan, WANG Shuaihao. Numerical Simulation Study on Characteristics and Prevention Methods of Ash Deposition in Thermal Power Units Flue[J]. Hunan Electric Power, 2025, 45(2): 63-68.

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