Physics
Scientific paper
Feb 2003
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2003icbg.conf...53o&link_type=abstract
Impact Cratering: Bridging the Gap Between Modeling and Observations, p. 53-54
Physics
Impactors, Thermal Stresses, Thermodynamics, Cavities, Craters, Damage, Particle Motion, Bonding, Collapse, Fracturing, Internal Friction, Near Fields, Scaling Laws, Shear Strain, Shock Waves
Scientific paper
The first objective of this effort is to determine how the post impact measurable crater features relate to the processes that take place during impact and the second is to the determine from a given suite of measurements the uncertainty in estimating the impactor's parameters. Approach. We have taken a numerical approach using the CTH code1 to calculate the evolution of the near field impact process. This includes the de-tails of the early time shock wave driven flow fields, the development and collapse of the transient cavity, and in a few limited cases the very late time thermal and stress histories. To quantify the impact process, we placed massless tracer particles in layers that simulate the target stratigraphy and stored the motion and thermo-mechanical state histories (e.g. pressure, temperature, damage, peak stress/strain rate..) of these particles. We took this approach because the late time distributions are significantly different from the initial distributions. We used the ANEOS model for equation of state and a Mohr-Coulomb damage model for the strength degradation by shear strain fracture. The key parameters for the impacts are a, the impactor radius, U, the impactor velocity, Yc, target cohesive strength, ?, internal friction, ?d, damaged internal friction. We found that we could replicate the key features with values of target material parameters within the magnitudes found in laboratory measurements. We developed scaling laws for the key target metrics based upon the Mohr-Coulomb strength model. This provides a the link between the measurable features and the impactor parameters,. In addition, it bounds the effect of damage on the magnitude of the metrics.
Ahrens Thomas J.
Okeefe John D.
No associations
LandOfFree
Impact Induced Target Thermo-Mechanical State and Particle Motion Histories does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Impact Induced Target Thermo-Mechanical State and Particle Motion Histories, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Impact Induced Target Thermo-Mechanical State and Particle Motion Histories will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-923135