Compression behavior of porous dust agglomerates

摘要: Context. The early planetesimal growth proceeds through a sequence of sticking collisions dust agglomerates. Very uncertain is still the relative velocity regime in which rather than destruction can take place. outcome collision depends on bulk properties porous Aims. Continuum models agglomerates require set material parameters that are often difficult to obtain from laboratory experiments. Here, we aim at determining those ab initio molecular dynamics simulations. Our goal improve existing model describe interaction individual monomers. Methods. We use approach featuring detailed micro-physical spherical grains. includes normal forces, rolling, twisting and sliding between present new treatment wall-particle allows us perform customized simulations directly correspond Results. find by Dominik & Tielens leads too soft compressive strength behavior for uniand omni-directional compression. Upon making rolling coefficients stiffer excellent agreement both cases. Additionally, curve with sample compressed. Conclusions. modified strengths two grains will lead different whole agglomerate. This influences probabilities hence planetesimals. parameter might possibly an enhanced as more energy be stored system before breakup.