Loose coupling modeling method for fluid-solid coupling heat transfer

Abstract

The invention provides a loose coupling modeling method for fluid-solid coupling heat transfer. The loose coupling modeling method is characterized in that the transient change process of a flow filed is ignored, and the global transient heat transfer process is assumed to be performed in a quasi-stable-state flow field. The method comprises the specific calculation procedures that 1, the flow field is updated, wherein only fluid is taken as a solving object, the fluid-solid coupling wall surface is set as a fixed temperature boundary of the fluid, and the flow field is solved through a stable-state CFD algorithm; 2, transient heat transfer is calculated, wherein the fluid and solid are both taken as the solving object, the fluid-solid coupling wall surface is set as a heat transfer coupling boundary, a momentum equation and a turbulent flow equation of the fluid are closed, and transient heat transfer is calculated until the flow field is updated for the next time and/or calculation stops; 3, the first step and the second step are repeated, wherein flow field updating and transient heat transfer calculating are alternately performed until the time arrives at the transient heat transfer termination moment. For the forced-convection heat transfer process of air in a pipe, by comparing the modeling method with a tight coupling calculation result of Fluent commercial software, the absolute error is 1 K or below, the calculation efficiency is improved by one order of magnitude, and the engineering calculation requirement is met.

Description

technical field [0001] The invention relates to a loose coupling modeling method of fluid-solid coupled heat transfer. Background technique [0002] At present, the transient CFD (computational fluid dynamics) method is mostly used in commercial software for single-phase fluid-solid coupled heat transfer problems to solve the flow field and to be coupled with solid heat transfer in real time. In the general commercial CFD software FLUENT, there are 4 main transient CFD methods: SIMPLE (semi-implicit method for pressure coupled equations), SIMPLEC (semi-implicit method for coordinated pressure coupled equations), PISO (implicit operator segmentation of pressure algorithm), FSM (finite state machine). At each time step iteration, the flow field in the fluid region is coupled to the temperature field, and the temperature field in the fluid region is coupled to the temperature field in the solid region. This algorithm has high precision and wide application range, but the calc...

AI Technical Summary

Problems solved by technology

The calculation efficiency of this algorithm is more than an order of magnitude higher than that of commercial software general algorithms, but the accuracy is low and does not conform to physical reality

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