Dielectrophoresis-driven jet impingement heat transfers in microgravity conditions

Abstract

In this paper, the ability of a pair of triangular electrodes to generate the steady dielectrophoresis-driven thermal convection of a dielectric liquid in a differentially heated cavity is investigated in microgravity conditions. A non-uniform electric field is created on purpose, which, together with a temperature gradient, gives rise to an internal convective flow essentially based on the presence of a pair of counter-rotating vortices. A numerical study is developed to investigate the subsequent benefits on heat transfers. The results seem to be in agreement with a background scaling analysis and demonstrate a significant increase in the Nusselt number for increasing voltages, provided that the dielectric liquid of interest is characterized by a moderate-to-large Prandtl number. The triangular electrodes yield a significant heat transfer enhancement when the same voltage is being used, by comparison with planar electrodes. This benefit is essentially due to jet impingement heat transfers that take place within the cavity.

Metastable Liquid Properties and Surface Flow Patterns of Ultrahigh Temperature Alloys Explored in Outer Space

“…[9][10][11][12][13][14][15] Especially, some novel properties and flow behaviors for a liquid in outer space has aroused great research interests in the fields of materials and chemistry. [16][17][18][19][20][21][22] Not only the liquid state is a fundamental problem in physical chemistry, surface chemistry and high temperature chemistry, [23][24][25][26][27] but also the research of liquid properties and the chemical bonds in outer space will play a significant role in multidisciplinary research connecting chemistry with space physics and metallic materials. [28][29][30][31] The metastable liquid thermophysical properties and surface flow patterns of refractory alloys with liquidus temperatures (T L ) beyond 2000 K face the challenges of high-temperature chemistry reactivity, intense volatilization, and droplet deformation.…”

Metastable Liquid Properties and Surface Flow Patterns of Ultrahigh Temperature Alloys Explored in Outer Space

“…[9][10][11][12][13][14][15] Especially, some novel properties and flow behaviors for a liquid in outer space has aroused great research interests in the fields of materials and chemistry. [16][17][18][19][20][21][22] Not only the liquid state is a fundamental problem in physical chemistry, surface chemistry and high temperature chemistry, [23][24][25][26][27] but also the research of liquid properties and the chemical bonds in outer space will play a significant role in multidisciplinary research connecting chemistry with space physics and metallic materials. [28][29][30][31] The metastable liquid thermophysical properties and surface flow patterns of refractory alloys with liquidus temperatures (T L ) beyond 2000 K face the challenges of high-temperature chemistry reactivity, intense volatilization, and droplet deformation.…”

“…However, there are still many mysteries for liquids at extraordinary environments, like superhigh or ultralow temperatures, and hyporgravity or microgravity [9–15] . Especially, some novel properties and flow behaviors for a liquid in outer space has aroused great research interests in the fields of materials and chemistry [16–22] . Not only the liquid state is a fundamental problem in physical chemistry, surface chemistry and high temperature chemistry, [23–27] but also the research of liquid properties and the chemical bonds in outer space will play a significant role in multidisciplinary research connecting chemistry with space physics and metallic materials [28–31] …”