Development of a multi-segment model for assessing the human body thermal conditions by modifying the blood circulatory system

Modeling body’s circulatory system with many vessels and capillaries and its effects on the body thermal conditions is complex. many thermoregulatory models have tried to model the effect of the circulatory system with simplistic and inaccurate assumptions. The MSTB model considers the blood as a node with specific heat capacity and constant temperature depends on the overall body thermal conditions. This assumption can lead to significant errors in estimating the some organs temperature. Therefore, a JOSTB model has been introduced by the approach of modifying the blood circulatory system. In this model, the body is divided into 17 segments and 3 layers and blood flow in the organs with arteries in the core of each segment is considered. The heat and mass transfer and the localized Pennes equations in different segments have been used to determine tissue temperature. Comparing JOSTB results with MSTB and experimental results show that JOSTB accurately predicts the body temperature. The average errors for the local skin temperature in the wide range of operative temperatures (10-50 ) are equal to 2.3  and 1.1   for MSTB and JOSTB.