A new local index for predicting local thermal response of individual body segments.

Physiologically, the thermal sensation/perception of human body is related to the response of cutaneous thermoreceptors (TRs) to the environment. However, the thermal response of skin warm and cold TRs is a function of two important factors: TRs temperatures and their time derivative at the subcutaneous locations of TRs. The available thermal models based on TRs response consider the same sensitivity for all thermal receptors of body. Thus, they estimate an average value of thermal response for whole body TRs. Therefore, considering the physiological thermal perception of humans, this study has presented a local thermal response index for estimating local sensation of different body segments based on local thermal response of individual TRs. Further, this index has used the ASHRAE thermal sensation scales to express the TRs thermal responses. Also, the new multi-segmental thermoregulatory bioheat model (MSTB) is utilized to calculate the individual TRs temperature. Finally, the predicted local thermal sensation by the new local index has been compared with published measured data under uniform/non-uniform thermal conditions. The results show that the local thermal sensation of individual body parts could be evaluated by the new local predictive index (LTRESP) with reasonable accuracy under various thermal conditions.