国际安全研究报告

康艳梅:Local thermal conductivity of inhomogeneous nano-fluidic films:A density functional theory perspective

作者:      来源:      发布时间:2024年05月17日
    摘要:Combining the mean field Pozhar–Gubbins(PG) theory and the weighted density approximation, a novel method for local thermal conductivity of inhomogeneous fluids is proposed. The correlation effect that is beyond the mean field treatment is taken into account by the simulation-based empirical correlations. The application of this method to confined argon in slit pore shows that its prediction agrees well with the simulation results, and that it performs better than the original PG theory as well as the local averaged density model(LADM). In its further application to the nano-fluidic films, the influences of fluid parameters and pore parameters on the thermal conductivity are calculated and investigated.It is found that both the local thermal conductivity and the overall thermal conductivity can be significantly modulated by these parameters. Specifically, in the supercritical states, the thermal conductivity of the confined fluid shows positive correlation to the bulk density as well as the temperature. However, when the bulk density is small, the thermal conductivity exhibits a decrease-increase transition as the temperature is increased. This is also the case in which the temperature is low. In fact, the decrease–increase transition in both the small-bulk-density and low-temperature cases arises from the capillary condensation in the pore. Furthermore, smaller pore width and/or stronger adsorption potential can raise the critical temperature for condensation, and then are beneficial to the enhancement of the thermal conductivity. These modulation behaviors of the local thermal conductivity lead immediately to the significant difference of the overall thermal conductivity in different phase regions.
        基金资助:

Project supported by the Fundamental Research Fund for the Central Universities of China; the Research Project for Independently Cultivate Talents of Hebei Agricultural University (Grant No. ZY2023007);

  • 专辑:

    基础科学

  • 专题:

    力学

  • 分类号:

    O35