Effect of Marangoni induced instabilities on a melting bridge under microgravity conditions

The present work is focused on the 3D numerical analyses of the n-octadecane melting process, under microgravity conditions and Marangoni convection, by using the configuration of the liquid bridges (melting bridge). These analyses were conducted for various temperature differences (AT) between hot and cold plates ranging from 18 K up to 50 K. The temperature oscillations in one point of the bridge volume showed distinctive behavior in three different ranges of AT. These domains have been fully characterized in terms of frequency and wave patterns. Standing and travelling wave modes of different wave numbers have been observed and the instabilities produced within their transitions have been deeply analyzed. The results showed that the complexity of the flow increased with AT and oscillation frequencies decreased while the melted fraction increased. Moreover, Marangoni convection enhanced the heat rate efficiency by a factor of 1.7 approximately compared to a pure conductive process, which depended on temperature difference applied. (c) 2021 Elsevier Ltd. All rights reserved.

Automated summary

The current study focuses on the 3D numerical analyses of n-octadecane melting process under microgravity conditions and Marangoni convection using liquid bridges configuration. It was found that the complexity of flow increased with the temperature difference (ΔT) between hot and cold plates, oscillation frequencies decreased, and the melted fraction increased with ΔT. Marangoni convection also enhanced heat rate efficiency by approximately 1.7 times compared to a pure conductive process.