Effect of Deflectors on the Flow Characteristics of a Square Pipe with a 90° Bend

doi:10.1007/s12204-021-2278-4

Abstract

Abstract: Pipe flow is a classic hydrodynamic issue. Most pipelines contain bends, and bends cause energy loss and distort the flow because of secondary flow. Deflectors are often used to adjust the flow quality in a bend. In this study, a numerical simulation using ANSYS Fluent 19.0 is used to analyze the effects of the deflector number, location and angle on the flow characteristics of a square pipe with a 90° bend. The velocity non-uniformity and the head loss are analyzed quantitatively. The secondary flow is presented visually, and its evolution characteristics are assessed. An optimized installation scheme for the deflectors is discussed, and a reference is provided for controlling the flow quality in bends via deflectors.

Key words: bend| deflector| head loss| secondary flow

摘要： Pipe flow is a classic hydrodynamic issue. Most pipelines contain bends, and bends cause energy loss and distort the flow because of secondary flow. Deflectors are often used to adjust the flow quality in a bend. In this study, a numerical simulation using ANSYS Fluent 19.0 is used to analyze the effects of the deflector number, location and angle on the flow characteristics of a square pipe with a 90° bend. The velocity non-uniformity and the head loss are analyzed quantitatively. The secondary flow is presented visually, and its evolution characteristics are assessed. An optimized installation scheme for the deflectors is discussed, and a reference is provided for controlling the flow quality in bends via deflectors.

关键词: bend| deflector| head loss| secondary flow

CLC Number:

O 352

JIANG Chenqi (江晨琦), GONG Zhaoxin (宫兆新) . Effect of Deflectors on the Flow Characteristics of a Square Pipe with a 90° Bend[J]. J Shanghai Jiaotong Univ Sci, 2021, 26(2): 163-169.

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