Fluid-solid node two-phase flow modeling method

Abstract

The invention discloses a fluid-solid node two-phase flow modeling method used for achieving gravity-driven fluid-structure interaction heat transfer of two-phase flow without phase change. The method is characterized in that accurate calculation of a flow field is ignored, and the two-phase flow is processed according to a node thermal network thought. The method specifically comprises the steps that A, a liquid phase and a gas phase are abstracted into nodes with certain mass, volume and temperature; B, a gravity direction volume integral is used for calculating the interface between the two phases; C, a surface radiation heat transfer model is used for calculating the radiation heat flux density of a fluid-structure interaction wall; D, the temperature of the gas phase and the temperature of the liquid phase are calculated according to the heat convection heat flux density of the fluid-structure interaction wall; E, solid transient heat conduction is calculated according to the total heat flux density of the fluid-structure interaction wall. Targeting the fluid-structure interaction heat transfer process of the two-phase flow in a typical fuel tank, compared with a calculated result obtained through a Fluent business software phase field method, the calculated result obtained through the modeling method better reflects the influence of the phase interface on heat transfer, calculation efficiency is improved by one order of magnitude, and the engineering calculation demand is met.

Description

technical field

[0001] The invention relates to a fluid-solid nodal two-phase flow modeling method. Background technique

[0002] At present, there are mainly two methods to solve the gravity-driven simple two-phase fluid-solid coupling heat transfer problem in engineering.

[0003] The first method solves the flow field in the two-phase flow region with a "phase field" approach based on the diffusion interface, coupled with the solid in real time. Mainly used in commercial CFD (computational fluid dynamics) software, such as FLUENT. The "phase field" method uses the order parameter φ a (x,t), φ b (x,t) models the spatial distribution of two phases a, b. In the region φ occupied by phase a a (x,t) is equal to 1, in the region where phase a does not exist φ a (x,t) is equal to 0, and in the diffusion interface around phase a φ a (x,t) varies continuously between 1 and 0. At any position in the flow field, φ a (x,t) and φ b The sum of (x,t) is equal to 1. In the dif...

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