基于单胞孔隙结构的多孔泡沫界面对流换热系数研究

Study on Convective Heat Transfer Coefficient of Porous Foam Interface Based on Single Cell Pore Structure

界面对流换热系数是采用局部热非平衡模型研究多孔泡沫流动传热过程的一个关键参数。本文采用体中心切球法构造多孔泡沫单胞孔隙结构来模拟多孔泡沫真实物理结构,在孔隙结构下进行流动换热过程的数值模拟,计算对流换热系数,并与文献中实验研究获取的努塞尔数对比以验证数值模拟准确性,然后对不同孔隙结构的多孔泡沫流动换热过程进行数值模拟计算,利用数据拟合建立界面对流换热系数准则关联式。基于建立的界面对流换热系数准则关联式,对多孔泡沫在局部热平衡及局部热非平衡两种假设下的流动传热过程进行宏观数值模拟,并与文献实验值进行对比,结果进一步验证了所建立关联式的准确性,说明基于单胞孔隙结构获取界面对流换热系数的方法是有效的,同时也验证了局部热非平衡模型能够更加精确地描述多孔泡沫的流动传热过程。

The interfacial convective heat transfer coefficient is a key parameter in the study of the flow and heat transfer process of porous foam using the local thermal non-equilibrium model.In this paper,the body center tangent sphere method is used to construct the cell pore structure of porous foam to simulate the real physical structure of porous foam.The numerical simulation of the flow and heat transfer process under the pore structure is carried out to calculate the convective heat transfer coefficient,and the Nusselt number obtained from the experimental research in the literature is compared to verify the accuracy of the numerical simulation.Then,the flow and heat transfer process of porous foam with different pore structures is numerically simulated,The criterion correlation of interfacial convection heat transfer coefficient is established by data fitting.Based on the established correlation of the interfacial convection heat transfer coefficient criterion,the macro numerical simulation of the flow and heat transfer process of porous foam under the two assumptions of local heat balance and local heat non-equilibrium was carried out and compared with the experimental values in the literature.The accuracy of the established correlation was further verified,indicating that the method of obtaining the interfacial convection heat transfer coefficient based on the structure of single cell pores was effective.It is also verified that the local thermal non-equilibrium model can more accurately describe the flow and heat transfer process of porous foam.