Motion of a fragmented meteoroid through the planetary atmosphere

Meteor observations and crater field investigations support the view that some meteoroids undergo fragmentation into a finite number of splinters which move a long distance without further disruption. The motion of these fragments cannot be described in the frame of liquid-like models. The primary purpose of this study is to achieve some success in improving the alternative model of separate fragments, which is based on studying the motion of a finite number of fragments interacting with each other through the air pressure. The three-dimensional (3-D) numerical technique is elaborated for the direct modeling of the flow around several arbitrarily arranged fragments. The model allows us to calculate the ablation mass rate and aerodynamic loading for each fragment. The new approach (hybrid model) based on the simultaneous solution of the 3-D hydrodynamic equations for the airflow and the differential equations for the motion of discrete particles is proposed to study the debris cloud evolution, taking into account successive fragmentation. The simplified version of this model was applied to the Sikhote-Alin meteorite shower, Benesov bolide, and small meteoroids' impacts against the Martian surface.