The Combined Thermal and Mechanical Effect of an Interstitial Gas on Thermal Rectification Between Periodically Grooved Surfaces

Kostyantyn Chumak,Rostyslav Martynyak

doi:10.3389/fmech.2019.00042

Abstract

This paper presents a study on the combined thermal and mechanical effect of interstitial gas on thermal rectification between a periodically grooved surface and a flat one. To evaluate the interstitial medium influence, the analytico-numerical solution to the corresponding thermoelastic contact problem is constructed taking into account the effect of thermal strains on gap deformation. The results are provided for the Stainless Steel AISI 304 – Aluminum Alloy A380 pair in the presence of air or krypton in the interface gaps. The effects of the gas thermal conductivity and pressure, the imposed pressure and heat flux, and the maximum groove height on the effective thermal contact resistance and the level of thermal rectification are analyzed. It is revealed that taking into account the mechanical effect of the gap filler leads to lower values of thermal rectification level. Also, the change of the gap filler thermal conductivity has more pronounced effect that the change of its pressure.

Highlights

Today the tribological mechanical components of many modern devices are often regularly textured with grooves, dimples, protrusions, etc. of small height in order to improve their surface properties significantly (Etsion, 2004, 2005; Stepien, 2011)
The essence of thermal rectification is that the thermal contact resistance between two bodies is greater in one heat flow direction across the interface than in the reverse direction
Calculations are performed for the Stainless Steel AISI 304—Aluminum Alloy A380 pair in the presence of air or krypton in the interface gaps

Summary

Introduction

Today the tribological mechanical components of many modern devices are often regularly textured with grooves, dimples, protrusions, etc. of small height in order to improve their surface properties significantly (Etsion, 2004, 2005; Stepien, 2011). The results of theoretical studies of thermoelastic contact between bodies of dissimilar materials in a vacuum environment (Barber, 1971; Dundurs and Panek, 1976; Stevenson et al, 1991; Kharitonov and Yakutin, 1997; Chumak and Martynyak, 2012) showed that the contact parameters and thermal contact resistance of the bodies depend on the heat flow density and on the reversal of its direction. This phenomenon was repeatedly observed experimentally [a review of these experimental observations is available in Roberts and Walker (2011)] and is known as Effect of Interstitial Gas on Thermal Rectification thermal rectification or the directional effect. Thermal rectification between textured surfaces is poorly investigated [the only study available was conducted by Chumak and Martynyak (2019)]

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