相关论文: Compression Behaviour of Porous Dust Agglomerates

In granular media, the presence of even small amounts of interparticle cohesion manifests as an increase in the bulk strength and stiffness, effects that are typically associated with an increase in the average number of constraints per…

Context: The streaming instability (SI) is a leading candidate for reaching solid densities sufficient to trigger the gravitational collapse needed for the formation of planetesimals. However, dust growth barriers appear to impede the…

The mechanics of cohesive or cemented granular materials is complex, combining the heterogeneous responses of granular media, like force chains, with clearly defined material properties. Here, we use a discrete element model (DEM)…

The thesis deals with the first stage of planet formation, namely dust coagulation from micron to millimeter sizes in circumstellar disks. For the first time, we collect and compile the recent laboratory experiments on dust aggregates into…

Recent observations of protoplanetary disks (PPDs) in the sub-mm have revealed the ubiquity of annular substructures, indicative of pebble-sized dust particles trapped in turbulent ring-like gas pressure bumps. This major paradigm shift…

The collision dynamics of dusty bodies are crucial for planetesimal formation. Especially decimeter agglomerates are important in the different formation models. Therefore, in continuation of our experiments on mutual decimeter collisions,…

Over the past years the processes involved in the growth of planetesimals have extensively been studied in the laboratory. Based on these experiments, a dust-aggregate collision model was developed upon which computer simulations were based…

To treat the problem of growing protoplanetary disc solids across the meter barrier, we consider a very simplified two-component coagulation-fragmentation model that consists of macroscopic boulders and smaller dust grains, the latter being…

We study stability of a dust layer in a gaseous disc subject to the linear axisymmetric perturbations. Instead of considering single-size particles, however, the population of dust particles is assumed to consist of two grain species. Dust…

Planet formation in the discs around young stars involves the coagulation of sub-micron sized dust grains into much larger grains that may be mixed by turbulence and migrate through the disc. In this paper, we describe how we have combined…

The structure and mechanical properties of a simple two-dimensional model of a cohesive powder are investigated by molecular dynamics simulations. Micromechanical ingredients involve elasticity, friction, a short range attraction and,…

Collisional evolution is a key process in planetesimal formation and decimetre bodies play a key role in the different models. However, the outcome of collisions between two dusty decimetre bodies has never been studied experimentally.…

The streaming instability is a promising mechanism for planetesimal formation. The instability can rapidly form dense clumps that collapse self-gravitationally, which is efficient for large dust grains with the Stokes number on the order of…

Compressive strength is a key to understanding the internal structure of dust aggregates in protoplanetary disks and their resultant bodies, such as comets and asteroids in the Solar System. Previous work has modeled the compressive…

We have studied formation of planetesimals at a radial pressure bump in a protoplanetary disk created by radially inhomogeneous magnetorotational instability (MRI), through three-dimensional resistive MHD simulations including dust…

Using numerical simulations, we study the dynamical evolution of particles interacting via competing long-range repulsion and short-range attraction in two dimensions. The particles are compressed using a time-dependent quasi-one…

If planetesimal formation is an efficient process, as suggested by several models involving gravitational collapse of pebble clouds, then, before long, a significant part of the primordial dust mass should be absorbed in many km sized…

The dynamics of planetesimals plays an important role in planet formation, because their velocity distribution sets the growth rate to larger bodies. When planetesimals form in protoplanetary discs, their orbits are nearly circular and…

The degree of coupling between the gas and the magnetic field during the collapse of a core and the subsequent formation of a disk depends on the assumed dust size distribution. We study the impact of grain-grain coagulation on the…

Context: Dust grains undergo significant growth in star-forming environments, especially in dense regions prone to gravitational collapse. Although dust is generally assumed to represent $1 \%$ of the gas mass, dust density variations are…