@article{PAR00008319,
  title = {{E}xperiments on turbulent metal-silicate mixing in a magma ocean},
  author = {{D}eguen, {R}. and {O}lson, {P}. and {C}ardin, {P}hilippe},
  editor = {},
  language = {{ENG}},
  abstract = {{W}e compare the results of laboratory fluid dynamics experiments with theoretical models of turbulent entrainment in two-phase buoyant plumes and thermals to estimate the amount of mixing between the iron core of a planetesimal or planetary embryo and the molten silicates in a magma pool formed by its impact with a growing planet during accretion. {W}e demonstrate experimentally that turbulent plumes in immiscible fluids fragment into droplets, and that the envelope of the droplet distribution is indistinguishable from the envelope of a turbulent plume in a single phase fluid under the same dynamical conditions, implying that turbulent entrainment concepts are applicable to immiscible fluids mixing. {A} series of experiments are made on the time evolution of a two-phase turbulent thermal, representing a planetesimal core, falling under its own negative buoyancy in a spherical fluid, representing an impact-produced magma pool. {T}wo stages of mixing are observed in these experiments: the first corresponding to turbulent entrainment during free-fall of the thermal, the second corresponding to entrainment in turbulent gravity currents that form after the thermal reaches the base of the magma pool. {W}e demonstrate that the amount of mixing between metals and silicate liquids in a magma pool depends on the {R}ouse number of the metal fragments and increases rapidly with the radius of the proto-planet. {W}e derive a similarity model for metal-silicate mixing in a spherical magma pool, assuming a constant entrainment coefficient for the turbulent liquid metal phase. {T}his model supports our experimental finding that a small metal core of an impactor will become diluted (i.e., mix) within a deep magma pool, but a large impacting core will not fully dilute before reaching the base of the magma pool.},
  keywords = {core formation ; magma ocean ; fragmentation ; turbulent mixing},
  booktitle = {},
  journal = {{E}arth and {P}lanetary {S}cience {L}etters},
  volume = {310},
  numero = {3-4},
  pages = {303--313},
  ISSN = {0012-821{X}},
  year = {2011},
  DOI = {10.1016/j.epsl.2011.08.041},
  URL = {https://www.documentation.ird.fr/hor/{PAR}00008319},
}