Related papers: Numerical modeling of the wind flow over a transve…
Orbital evolution of an interplanetary dust particle under action of an interstellar gas flow is investigated. Secular time derivatives of the particle orbital elements, for arbitrary orbit orientation, are presented. An important result…
Landforms such as sand dunes act as roughness elements to Atmospheric Boundary Layer (ABL) flows, triggering the development of new scales of turbulent motions. These turbulent motions, in turn, energize and kick-up sand particles,…
Wind turbines operate in the atmospheric boundary layer, where they are exposed to the turbulent atmospheric flows. As the response time of wind turbine is typically in the range of seconds, they are affected by the small scale intermittent…
We analyze turbulent velocity signals measured by two probes in the atmosphere, both at the height of 35 meters but displaced by 40 cm nominally orthogonal to the mean wind. Choosing a suitable coordinate system with respect to that of the…
Winds from massive stars (> 8 solar masses) result in the formation of wind-blown "bubbles" around these stars. In this paper we study, via two-dimensional numerical hydrodynamic simulations, the onset and growth of turbulence during the…
The solar wind is a magnetized and turbulent plasma. Its turbulence is often dominated by Alfv\'enic fluctuations and often deemed as nearly incompressible far away from the Sun, as shown by in-situ measurements near 1AU. However, for solar…
The eccentric WR+O binary system WR 140 produces dust for a few months at intervals of 7.94 yrs coincident with periastron passage. We present the first resolved images of this dust shell, at binary phases ~0.039 and ~0.055, using aperture…
Contemporary three-dimensional physics-based simulations of the solar convection zone disagree with observations. They feature differential rotation substantially different from the true rotation inferred by solar helioseismology and…
The heating of the solar wind is a key to understand its dynamics and acceleration process. The observed radial decrease of proton temperature in the solar wind is slow compared to the adiabatic prediction and it is thought to be caused by…
Stellar winds of cool carbon stars enrich the interstellar medium with significant amounts of carbon and dust. We present a study of the influence of two-fluid flow on winds where we add descriptions of frequency-dependent radiative…
We study numerically the propagation of a hot thermal transient through a U-bend via an ensemble of wall-resolved large eddy simulations. Conjugate heat transfer between fluid and solid domains is accounted for. The flow is in a fully…
We address the problem of calculating the transverse magnetic field in the solar wind outside of the hypothetical sphere called the source surface where the solar wind originates. This calculation must overcome a widely used fundamental…
Turbulent boundary layers over flat walls in the presence of a hill are frequently found in nature and industry. Some examples are the air flows over hills and desert dunes, but also water flows over aquatic dunes inside closed conduits.…
We investigate the formation of dust traffic jams in polar-aligning circumbinary discs. We use 3D smoothed particle hydrodynamical simulations of both gas and dust to model an initially highly misaligned circumbinary disc around an…
The dynamics of the upper mesosphere of Venus (~85-115 km) have been characterized as a combination of a retrograde superrotating zonal wind (RSZ) with a subsolar-to-antisolar flow (SSAS). Numerous mm-wave single-dish observations have been…
Winds from massive stars have velocities of 1000 km/s or more, and produce hot, high pressure gas when they shock. We develop a theory for the evolution of bubbles driven by the collective winds from star clusters early in their lifetimes,…
The current research focuses on mesoscale dynamics of the atmospheric circulation around an idealized coastal cape representing typical summertime circulation along the northwest coast of the U.S., studied using a mesoscale coupled…
Barchans are isolated mobile dunes often organized in large dune fields. Dune fields seem to present a characteristic dune size and spacing, which suggests a cooperative behavior based on dune interaction. In Duran et al. (2009), we propose…
We investigate the gas-grain relative drift velocity distributions of charged astrophysical dust grains in MHD turbulence. We do this using a range of MHD-PIC simulations spanning different plasma-$\beta$, sonic/Alfv\'en Mach number, and…
In nature, barchan dunes typically exist as members of larger fields that display striking, enigmatic structures that cannot be readily explained by examining the dynamics at the scale of single dunes, or by appealing to patterns in…