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Related papers: Dune initiation in a bimodal wind regime

200 papers

We performed large-eddy simulations of the flow over a typical two-dimensional dune geometry at laboratory scale (the Reynolds number based on the average channel height and mean velocity is 18,900) using the Lagrangian dynamic…

Fluid Dynamics · Physics 2011-10-07 Mohammad Omidyeganeh , Ugo Piomelli

We analyze the linear stability of monoclinal traveling waves on a constant incline, which connect uniform flowing regions of differing depths. The classical shallow-water equations are employed, subject to a general resistive drag term.…

Fluid Dynamics · Physics 2022-05-18 Jake Langham , Andrew J. Hogg

Hydrodynamical simulations played an important role in understanding the dynamics and shaping of planetary nebulae in the past century. However, hydrodynamical simulations were just a first order approach. The new millennium arrived with…

Astrophysics · Physics 2015-06-24 Garcia-Segura

The streaming instability is a promising mechanism to induce the formation of planetesimals. Nonetheless, this process has been found in previous studies to require either a dust-to-gas surface density ratio or a dust size that is enhanced…

Earth and Planetary Astrophysics · Physics 2022-10-19 Urs Schäfer , Anders Johansen

[Abridged] Context: Radiation-driven mass loss plays a key role in the life-cycles of massive stars. However, basic predictions of such mass loss still suffer from significant quantitative uncertainties. Aims: We develop new…

Solar and Stellar Astrophysics · Physics 2020-01-08 J. O. Sundqvist , R. Björklund , J. Puls , F. Najarro

Dust grains embedded in gas flow give rise to a class of hydrodynamic instabilities, called resonant drag instabilities. These instabilities have predominantly been studied for single grain sizes, in which case they are found to grow fast.…

Earth and Planetary Astrophysics · Physics 2025-05-07 Sijme-Jan Paardekooper , Hossam Aly

The transport of solid particles by a fluid flow is frequently found in nature and industry. Some examples are the transport of sand in rivers and hydrocarbon pipelines. When the shear stresses exerted by a fluid flow on a granular bed…

Fluid Dynamics · Physics 2016-08-18 Jorge Eduar Cardona Florez , Erick de Moraes Franklin

We report an experimental investigation of aeolian sand ripples, performed both in a wind tunnel and on stoss slopes of dunes. Starting from a flat bed, we can identify three regimes: appearance of an initial wavelength, coarsening of the…

Soft Condensed Matter · Physics 2007-05-23 Bruno Andreotti , Philippe Claudin , Olivier Pouliquen

We derive the single-fluid evolution equations describing a mixture made of a gas phase and an arbitrary number of dust phases, generalising the approach developed in Laibe & Price (2014a). A generalisation for continuous dust distributions…

Earth and Planetary Astrophysics · Physics 2015-06-22 Guillaume Laibe , Daniel J. Price

Radiation-dust driven outflows, where radiation pressure on dust grains accelerates gas, occur in many astrophysical environments. Almost all previous numerical studies of these systems have assumed that the dust was perfectly-coupled to…

The origin of observed planetary systems, including our Solar System, as well as their diversity, is still an open question. Streaming instability (SI) is an important mechanism for the formation of gravitationally bound planetesimals,…

Earth and Planetary Astrophysics · Physics 2025-07-02 Kundan Kadam , Zsolt Regály

In this paper, the variable wind power is incorporated into the dynamic model for long-term stability analysis. A theory-based method is proposed for power systems with wind power to conduct long-term stability analysis, which is able to…

Systems and Control · Computer Science 2016-11-15 Xiaozhe Wang , Hsiao-Dong Chiang , Jianhui Wang , Hui Liu , Tao Wang

We propose a new evolutionary process of protoplanetary disks "co-evolution of dust grains and protoplanetary disks", revealed by dust-gas two-fluid non-ideal magnetohydrodynamics simulations considering the growth of dust and associated…

Solar and Stellar Astrophysics · Physics 2023-07-26 Yusuke Tsukamoto , Masahiro N. Machida , Shu-ichiro Inutsuka

Reliably predicting the geomorphology and climate of planetary bodies requires knowledge of the dynamic threshold wind shear velocity below which saltation transport ceases. Here we measure this threshold in a wind tunnel for four…

Geophysics · Physics 2019-10-28 Wei Zhu , Xinghui Huo , Jie Zhang , Peng Wang , Thomas Pähtz , Ning Huang , Zhiguo He

We consider the three-dimensional instability of a layer of horizontal magnetic field in a polytropic atmosphere where, contrary to previous studies, the field lines in the initial state are not unidirectional. We show that if the twist is…

Solar and Stellar Astrophysics · Physics 2015-03-20 B. F. N. Favier , L. Jouve , W. Edmunds , L. J. Silvers , M. R. E. Proctor

We model the evolution of the snow line in a protoplanetary disc. If the magneto-rotational instability (MRI) drives turbulence throughout the disc, there is a unique snow line outside of which the disc is icy. The snow line moves closer to…

Earth and Planetary Astrophysics · Physics 2015-06-05 Rebecca G. Martin , Mario Livio

The formation of planetesimals in protoplanetary disks due to collisional sticking of smaller dust aggregates has to face at least two severe obstacles, namely the rapid loss of material due to radial inward drift and particle fragmentation…

Astrophysics · Physics 2009-11-13 F. Brauer , Th. Henning , C. P. Dullemond

Aims. We numerically investigated dust enrichment and growth during the initial stages of protoplanetary disk formation. A particular objective was to determine the effects of various growth barriers, mimicked by imposing a series of upper…

Earth and Planetary Astrophysics · Physics 2025-07-02 E. I. Vorobyov , V. G. Elbakyan , A. Skliarevskii , V. Akimkin , I. Kulikov

Observations with the Atacama Large Millimeter/submillimeter Array (ALMA) and the Jansky Very Large Array (JVLA) have revealed many dust rings in protoplanetary disks, often interpreted as dust traps at gas pressure bumps. Previous studies…

Earth and Planetary Astrophysics · Physics 2025-07-15 Linhan Yang , Ya-Ping Li , Ruobing Dong , Kiyoaki Doi , Hauyu Baobab Liu , Pinghui Huang

The streaming instability is thought to play a central role in the early stages of planet formation by enabling the efficient bypass of a number of barriers hindering the formation of planetesimals. We present the first study exploring the…

Earth and Planetary Astrophysics · Physics 2019-06-19 Leonardo Krapp , Pablo Benítez-Llambay , Oliver Gressel , Martin E. Pessah