Author(s)

K. Ueyama

Abstract

Corrections to the conventional two-fluid model equations are briefly illustrated, showing the general expression of the two-fluid model equation without any restriction on averaging, the general expression of the interaction term with ‘inside-out’ property, and the corrected two-fluid model equation with a new and novel term reflecting the ‘inside-out’ property of the interaction term. On the basis of the corrected two-fluid model equation, several questions are stated and discussed for Euler–Lagrange type simulator with respect to the moving velocity of individual drop and fluctuating motion of drops, and new concepts for Euler–Lagrange and Euler–Euler type of simulators are proposed focusing on the fluctuating motion of drops, which is one of the representative phenomena in the dispersed multiphase flow. Keywords: fluctuating motion of drops, dispersion of drops, Euler–Lagrange type simulator, Euler–Euler type simulator. 1 Introduction Recently, a flaw in the basis of the conventional two-fluid model equation based on volume-averaging was revealed [8]. It was shown that the restriction, that the control volume must be between the drop size and the scale of macroscopic variations, was unrealistic for treating multiphase flow with spatial variation of macroscopic properties, and the two-fluid equation has been derived without any restriction on averaging, by combining volume-averaging and time-averaging. The most important founding in the work is that the interaction term has \“inside-

Keywords

fluctuating motion of drops, dispersion of drops, Euler–Lagrangetype simulator, Euler–Euler type simulator