Mathematical modeling of the corpse cooling under conditions of varying ambient temperature

Abstract

Background: The constancy of the ambient temperature is the main condition to correctly determine the time of death by thermometric method. However, in practice, this requirement is met only in cases of death in closed rooms. In this study, an exponential mathematical model was proposed for corpse cooling under any changes in ambient temperature. Aim: This study aimed to develop a mathematical model to determine the time of death based on the Newton–Richman cooling law in changing ambient temperature conditions. Materials and methods: Mathematical modeling of corpse cooling under changing ambient temperature is performed, focusing on problem solving of thermometric determination of the time of death. The axillary hollow was used as the diagnostic zone of the corpse, and the temperature of which at the time of death is taken is 36.6°С. Results: A method of reverse reproduction of the cadaver temperature in conditions of changing ambient temperature has been developed. Results allow a relatively simple analytical determination of the time of death in the early postmortem period. Conclusions: The proposed method is advisable to be used in forensic medical practice to determine the time of death in early postmortem period. The developed mathematical model is implemented in the format of the application program Warm Bodies NRN. Use of tympanic and intraocular thermometry was recommended within the proposed model.

Keywords

Newton–Richman law of cooling / time of death / mathematical modeling / and ambient temperature

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Nedugov G.V.