Numerical simulation of bolide entry with ground footprint prediction

As they decelerate through the atmosphere, meteors transfer mass, momentum and energy into the surrounding air at tremendous rates. The entry of such bolides produces strong blast waves that can propagate hundreds of kilometers and cause substantial terrestrial damage even when no ground impact occurs. We develop a new technique for meteoroid airburst modeling based upon conservation analysis for the deposition of mass, momentum and energy. These sources are then used to drive simulations of blast propagation using a fully-conservative, finite-volume solver on a multilevel Cartesian mesh. We examine the ability of this method to accurately propagate the blast over hundreds of kilometers of terrain. Initial verification of the method is presented through the canonical problem of a spherical charge. A detailed reconstruction of the 2013 Chelyabinsk meteor provides additional validation. These simulations show very good prediction of the surface overpressure and blast arrival times throughout the ground footprint. Further investigations examine the impact of simplifications to the modeling on both accuracy and computational efficiency using a line-source blast model and a static spherical charge. Both approaches are shown to be useful simplifications and limitations on their use are discussed.