Effects of nanosized contact spots on thermal contact resistance

Abstract

We investigate the effects of nanosized contact spots on the thermal contact resistance ͑TCR͒ in multiscale contacts. As the contact size decreases below the phonon mean free path, the thermal conductivity varies with the size of the contact and is not the same as its bulk counterpart. We take this into account in our model and we calculate the TCR of silicon contacted with other silicon. The TCR increases as the number of nanosized contact spots increases. However, if we do not consider the thermal conductivity reduction as the contact size decreases below the size of the phonon mean free path, there is a finite limit of the TCR. A parametric study on the effects of distance and size of the contact spots is also presented.

Effect of deformation on the thermal conductivity of granular porous media with rough grain surface

“…As far as conduction in systems with such rough surfaces is concerned, Majumdar and Tien [1991] presented a model for two rough fractal surfaces that was capable of estimating the thermal contact resistance. Several other such analytical models for conductions in porous media with rough surfaces exist [Zhang et al, 2004;Lee et al, 2008;Wang and Zhao, 2010;Belghazi et al, 2010]. Several other such analytical models for conductions in porous media with rough surfaces exist [Zhang et al, 2004;Lee et al, 2008;Wang and Zhao, 2010;Belghazi et al, 2010].…”

“…Fyrillas and Pozrikidis [2001] developed an analytical model for periodic rough surfaces with small amplitudes, while Laraqi and Bairi [2002] developed a similar model in which the contact area was composed of numerous circles of various radii that were randomly distributed over the contacting surfaces. Several other such analytical models for conductions in porous media with rough surfaces exist [Zhang et al, 2004;Lee et al, 2008;Wang and Zhao, 2010;Belghazi et al, 2010]. There have also been several studies of conduction in dry soil and other types of granular media [Yun and Santamarina, 2008;Wang et al, 2013;Tsory et al, 2013;Askari et al, 2015Askari et al, , 2016.…”

A Condition for Complete Flattening of Asperities in a Rough Contact

“…The asperities of higher level will change the real contact area. The calculations carried out in the first approximation show the tendency for it to decrease [7,16]. The quantitation of influence of higher level asperities at elastic-plastic material behavior is a key issue for future research.…”

“…To date a number of models of thermal contact conductance through multi-spot contact are developed, for example, see [7,[13][14][15][16], from which it is possible to distinguish finite element models [7,15,16]. It is to finiteelement models that they are increasingly turning to validate analytical stochastic models, for example, [17][18][19][20].…”

Multiscale Electrical Contact Resistance Between Gas Diffusion Layer and Bipolar Plate in Proton Exchange Membrane Fuel Cells

“…To achieve this objective, it is necessary to consider the current research trend for the analysis of contact between rough surfaces and to identify the differences between the contact of disparate materials such as metal or carbon fiber. For the analysis of contact with rough surfaces, it is believed that multiscale contact analysis [9,20,21] can predict the contact morphology explicitly, particularly considering that the refined surface mesh resolves into clusters of smaller contact area, the number of contact spots increases, and the actual contact area progressively decreases. Thus, the contact resistance is subject to the contact process, requiring the contact analysis to be performed relative to the proper scale.…”