A Simple Thermodynamical Theory for Dust Devils

Abstract

Based on the heat engine framework, a simple scaling theory for dust devils is proposed and compared to observations. This theory provides a simple physical interpretation for many of the observed characteristics of dust devils. In particular, it predicts the potential intensity and the diurnal variation of dust devil occurrence. It also predicts that the intensity of dust devils depends on the product of two thermodynamic efficiencies, corresponding respectively to vertical and horizontal temperature gradients.

Field Measurements of Terrestrial and Martian Dust Devils

“…Further, atmospheric modeling (Tyler and Barnes 2013; suggested that the depth of the daytime boundary layer inside the crater is suppressed. This suppressed, shallow depth was expected to reduce vortex activity, or at least vortex intensity, since the thermodynamic efficiency of vortices depends upon the boundary layer depth according to the so-called heat engine model (Renno et al 1998(Renno et al , 2000. Nevertheless, an extensive campaign of imaging Dust Devil Search Movies was initiated after MSL's landing (Moores et al 2015).…”

Dust Devil Sediment Transport: From Lab to Field to Global Impact

“…They assumed that individual dust devils lift dust at a rate of 0.7 × 10 −3 kg m −2 s −1 , based on field measurements of dust concentration and vertical wind speed in dust devils (Kaimal and Businger 1970;Renno et al 2004). They then used the thermodynamic theory for dust devils of Renno and Ingersoll (1996) and Renno et al (1998) to estimate the fractional area over which dust devils should be active. The theory developed by Renno et al (1998) describes a convective vortex (dust devil) as a heat engine that performs mechanical work against frictional dissipation.…”

“…They then used the thermodynamic theory for dust devils of Renno and Ingersoll (1996) and Renno et al (1998) to estimate the fractional area over which dust devils should be active. The theory developed by Renno et al (1998) describes a convective vortex (dust devil) as a heat engine that performs mechanical work against frictional dissipation. Driven by this convective heat engine, the dust devil activity, F av , is approximated by…”

“…Basu et al 2004), to the 'dust devil activity' metric defined by Renno et al (1998) or a combination of the Renno et al (1998) thermodynamic theory with measurements of dust lifting by a laboratory-produced vortex (e.g.…”

Electric and magnetic signatures of dust devils from the 2000–2001 MATADOR desert tests

“…In this latter case, shear stress is not the lifting mechanism. Instead light grains are drawn vertically by rising air driven by an atmospheric convective instability reacting to the inversion of a warm air mass below a cooler mass [Renno et al, 1998]. …”