Modeling the effect of gas on the effective thermal conductivity of heterogeneous materials. (November 2015)

• Record Type: Journal Article
• Authors: Pan, Liao; Lu, Lixin; Wang, Jun; Qiu, Xiaolin
• Is Part Of: International journal of heat and mass transfer. Volume 90(2015:Nov.)
• Page Start: 358
• Page End: 363
• Publication Date: 2015-11
• Subjects: Effective thermal conductivity -- Models -- Gas phase -- Heterogeneous material; Heat -- Transmission -- Periodicals; Mass transfer -- Periodicals; Chaleur -- Transmission -- Périodiques; Transfert de masse -- Périodiques; Electronic journals; 621.4022
• DOI: 10.1016/j.ijheatmasstransfer.2015.06.053
• Languages: English
• ISSNs: 0017-9310

Abstract

Highlights: The aim of this research is to study the effect of gas phase on the effective thermal conductivity of heterogeneous materials with high solid phase mass fraction. A general model based on Maxwell–Eucken model and Effective Medium Theory model was proposed first, then compared with the previous models and experimental data. The effects of the shape parameters of solid particle on the gas phase and the maximum volume fraction of solid phase were discussed. The results indicate the effective thermal conductivity of heterogeneous materials is significantly affected by gas phase, and the gas phase was determined by the maximum volume fraction of solid phase which was affected by the shape parameters of solid particle. The proposed model shows great agreement with test results. Abstract: The aim of this research is to study the effect of gas phase on the effective thermal conductivity of heterogeneous materials with high solid phase mass fraction. A general model based on Maxwell–Eucken model and Effective Medium Theory model was proposed first and compared with the previous models, showing some potential significance of the present model. The present model shows that the gas phase in heterogeneous materials is significantly affected by maximum volume fraction of solid phase. Then, the effect of the shape parameters of solid particle on the maximum volume fraction of solid phase was discussed. The results indicate the maximum volume fraction of solid phase tends to grow up by increasing the particle diameter or decreasing the particle diameter ratio. Finally, the effective thermal conductivity of heterogeneous materials predicted by the proposed model was compared with that by direct experiment, showing great agreement.