The Proceedings of the Eighth International Conference on Creationism (2018)

Seely et al. ◀ Finite element analysis of a near impact event ▶ 2018 ICC 63 a strain-rate and temperature dependent plasticity ISV model with temperature and pressure dependent moduli and yield surfaces. A DOE study was conducted to study the critical parameters influencing the surface rise and fall during a near pass event. The study revealed that the core material and core/mantle ratio are critical parameters for surface deformations occurring on all faces of the body and along with body size are the driving factors behind the Poisson’s contraction observed in the out-of-plane direction. The surface elevation change during the near pass of a moon sized object would cause a large surface rise (400 m) inevitably creating large tsunamis and causing large sedimentation on the continent surfaces. Detailed insights into the plastic response of the mantle are investigated through the evolution of ISV parameters and show that isotropic hardening and recovery lead to the permanent plastic deformation observed on the leading surface of the body potentially nucleating cracks in the Earth’s crust. This work introduces a framework for the investigation of dissipation mechanisms associated with near pass events within the Solar System. The incorporation of an ISV model allows for the plastic behavior to be determined, subsequently allowing for the heat generation due to plastic deformation to be accounted for during near pass, tidal, and/or resonance disturbances and a host of other boundary value problems involving gravitational disturbances and their resulting deformations. REFERENCES Agnor, C. B., R.M. Canup, and H.F. Levison. 1999. On the character and consequences of large impacts in the late stage of terrestrial planet formation. Icarus 142, no. 1: 219-237. Bammann, D.J. 1990. Modeling temperature and strain rate dependent large of metals. Applied Mechanics Reviews 43, no. 5: 312-319. Bammann, D.J., M.L. Chiesa, M.F. Horstemeyer, and L.I. Weingarten. 1993. Failure in ductile materials using finite element methods. Structural Crashworthiness and Failure , eds. T. Wierzbicki, and N. Jones, Elsevier Applied Science, The Universities Press (Belfast) Ltd. Figure 12. Isotropic hardening (kappa or SDV7) for cross sections of the stationary body (model Earth) along the equatorial x-y plane calculated from the internal state variable elastic-plastic model used for the mantle material. Counter clockwise from the upper left are shown isotropic hardening at time steps referenced to time of nearest passage. The pattern is not symmetric about the plane of nearest passage, but matches closely with the equivalent plastic strain.