Abstract The scope of this work is to investigate how the interfacial pressure and the scale of the asperities as well as the temperature, influence the thermal contact conductance TCC in rough surfaces under low pressure. For that, a two- dimensional numerical model is developed, in which the macroscopic TCC coefficient is obtained from the solution of the heat conduction problem at the scale of asperities. The morphology of the rough surface, which is characterized by a fractal interpolation function, is applied to mechanical and thermal modeling. The contact model calculates the different contact scales at the asperities by considering elastic, elastic–plastic and fully plastic deformations as well as the changes in material parameters due to the temperature. Finally, several contacting asperities are combined to get the macroscopic TCC coefficient. The obtained results showed that at small values of normal pressure, TCC becomes smaller at higher resolutions of the interface where waviness is more intense. On the contrary, the rate of increase of TCC with the increase of the normal pressure is larger at these interfaces at larger values of normal pressure, where the smaller scales of asperities deform more easily. This phenomenon appears to be more intense with the time as the temperature of the interface rises and consequently more plastifications of the asperities occur.

中文翻译：

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低外加压力下粗糙表面热接触传导的多尺度模型

摘要 这项工作的范围是研究界面压力和凹凸不平的尺度以及温度如何影响低压下粗糙表面的热接触电导TCC。为此，开发了二维数值模型，其中宏观 TCC 系数是从粗糙尺度的热传导问题的解决方案中获得的。以分形插值函数为特征的粗糙表面的形态被应用于机械和热建模。接触模型通过考虑弹性、弹塑性和完全塑性变形以及材料参数随温度的变化来计算粗糙处的不同接触尺度。最后，几个接触的凹凸相结合得到宏观的 TCC 系数。获得的结果表明，在较小的正常压力值下，TCC 在界面的分辨率较高时变得更小，其中波纹度更强烈。相反，在这些界面处，随着法向压力的增加，TCC 的增加率更大，常压值越大，越小尺度的凹凸不平越容易变形。随着时间的推移，随着界面温度的升高，这种现象似乎更加强烈，因此会出现更多的凹凸体塑化。在这些界面处，随着法向压力的增加，TCC 的增加率越大，常压值越大，越小尺度的凹凸不平越容易变形。随着时间的推移，随着界面温度的升高，这种现象似乎更加强烈，因此会出现更多的凹凸体塑化。在这些界面处，随着法向压力的增加，TCC 的增加率越大，常压值越大，越小尺度的凹凸不平越容易变形。随着时间的推移，随着界面温度的升高，这种现象似乎更加强烈，因此会出现更多的凹凸体塑化。