円形から長方形断面に変化する遷移ダクト内の乱流構造数値解析

概要

論文の詳細を見る
Numerical analysis is used to investigate three-dimensional turbulent structure and fluid flow behavior in a circular-to-rectangular transition duct. Turbulent flow through a circular-to-rectangular duct is characterized by streamwise curvature and streamwise vorticity embedded in the boundary layer. In the calculation, an algebraic Reynolds stress model together with a boundary-fitted coordinate system is applied to to a circular-to rectangular duct in order to solve anisotropic turbulent flow precisely. The calculated results are compared with the experimental results to examine the validity of the present method. As a result of this calculation, it is found that the present method predicts well a secondary flow pattern which develops into a discrete vortex pair along the duct sidewalls. This secondary flow arises as a result of lateral skewing of the near-wall flow in the vicinity of the sidewall induced by transverse pressure gradients associated with wall curvature. Moreover, the calculated contours of six Reynolds stress components are shown for comparison with the experiment. The distortion of Reynolds stresses by the vortex pair is clearly observed as well as the primary flow. Although agreement is not perfect, the main features are reproduced by the present method using the algebraic Reynolds stress model.
一般社団法人日本機械学会の論文
1996-09-25