Demonstration of a rarefied gas flow induced near the edge of a uniformly heated plate

Abstract

A new type of a rarefied gas flow, which was found numerically by the research group of the first author, is demonstrated by a simple experiment. It is a steady flow induced by the edge effect of a uniformly heated plate. The experiment is carried out in a standard bell jar, and small windmills are used to detect flows. The flow found by the numerical computation is observed. The cause of the flow is discussed and attributed to the edge effect of the heated plate.

Rarefied gas flow around a sharp edge induced by a temperature field

“…It should be noted, however, that the heat-conduction equation is not guaranteed to give a correct description of the temperature field in general even in the continuum limit (Sone et al 1996;Sone 2002Sone , 2007. Therefore, it requires further validation either numerically or mathematically, as mentioned in Sone & Yoshimoto (1997). The present result provides a numerical justification for the previous estimate.…”

“…A natural implication of this is that the thermal edge flow and the radiometric flow are induced by the same underlying mechanism and thus are of the same type of the temperature-driven flow. Motivated by this thought, we now try to apply the same reasoning behind the thermal edge flow (Sone & Yoshimoto 1997) to explain the cause of the radiometric flow. That is, along …”

“…Since there is no analytical solution available, we shall exploit here, for simplicity, the solution of the heat-conduction equation. Indeed, it was in this way that Sone & Yoshimoto (1997) were able to arrive at an estimate of the magnitude of the thermal edge flow. First, we consider the case of the thermal edge flow.…”

“…In this way, the state with no flow everywhere is established in the continuum limit. It should be mentioned that Sone & Yoshimoto (1997) gave a rough analytical estimate of the speed of the thermal edge flow. According to them, it is proportional to the square root of the mean free path.…”

Heat transfer in micro devices packaged in partial vacuum

“…The R13 equations are an extension to the classical Navier-Stokes-Fourier (NSF) equations of hydrodynamics. An analysis of the order of Knudsen number in (3)(4) shows that only the underlined terms are of first order in Knudsen number, while all others are of higher order [34]. Thus, the underlined terms are the NSF contributions,…”