THERMODE 2023: Formulation and Validation of a new Thermo-physiological Model for Moderate Environments

Abstract

Thermo-physiological models allow the evaluation of the human response to thermal environments, assessing thermal comfort and (or) thermal stress due to exposure to heat and cold, in clothing and automotive research, and building simulation. Fifty years after the final version of the model developed by Stolwijk over the period 1966–1973, this paper describes a novel multi-cylindrical model which integrates the most recent advances in the active and the passive components and a thermal sensation model. The model, named THERMODE (THERMoregulation MOdel for Disuniform Environments) 2023, will be presented in-depth to allow its independent implementation by researchers in the field and favour further developments. Consisting of 14 blocks, 48 segments, and 193 nodes, THERMODE has been validated based on climatic chamber measurements carried out on nine groups of twelve subjects in a range of thermal sensations close to comfort (e.g., from slightly cool (−1) to slightly warm (+1) according to the ASHRAE scale). THERMODE predicts with acceptable accuracy core and local skin temperature values with deviations that do not exceed 0.5 °C in moderate environments. The thermal sensation model was validated on a sample of more than 4000 subjects and predicts with high accuracy the thermal sensation in the range from −1.2 to 2.0. THERMODE seems to be also reliable in a broader range of microclimatic conditions with skin and core temperatures close to those predicted by other models (e.g., JOS-3 or 3-D).