On models of meteoroid disruption into the cloud of fragments

Abstract

The meteoroid disruption into a large number of fragments when they move with a common shock wave before dispersion to a sufficient distance to move independently is considered. Disrupted meteoroid under the action of pressure forces is deformed: it is compressed in a flight direction and expands in a lateral one. Four models of the meteoroid disruption into a cloud of fragments moving as a single body are considered: two models developed by the authors and two models used in the literature (Grigoryan, 1979; Hills and Goda, 1993). The principal differences between the proposed and accepted models are shown. Numerical solutions of the meteor physics equations are obtained using the above models to simulate the interaction of the Chelyabinsk meteoroid with the atmosphere. To model the meteoroid ablation, an approximate formula is used for the radiative heat transfer coefficient as a function of the meteoroid velocity and size and the atmospheric density. The influence of the heat transfer coefficient uncertainty (including its constant value) on the meteoroid mass loss, energy deposition and initial mass estimate is studied. Solutions using different fragmentation models are compared with each other and with observational data and the results of comparisons are discussed.