Use of a Thermal Manikin to Evaluate Human Thermoregulatory Responses in Transient, Non-Uniform, Thermal Environments

Abstract

People who wear protective uniforms that inhibit evaporation of sweat can experience reduced productivity and even health risks when their bodies cannot cool themselves. This paper describes a new sweating manikin and a numerical model of the human thermoregulatory system that evaluates the thermal response of an individual to transient, non-uniform thermal environments. The physiological model of the human thermoregulatory system controls a thermal manikin, resulting in surface temperature distributions representative of the human body. For example, surface temperatures of the extremities are cooler than those of the torso and head. The manikin contains batteries, a water reservoir, and wireless communications and controls that enable it to operate as long as 2 hours without external connections. The manikin has 120 separately controlled heating and sweating zones that result in high resolution for surface temperature, heat flux, and sweating control. The physiological finite element model uses approximately 40,000 solid thermal and blood network elements to represent the human body. The manikin and physiological model demonstrate their value in evaluating the thermoregulatory response of a person in a protective uniform. They can also be used to evaluate the effectiveness of personal cooling systems.

Opportunities and constraints of presently used thermal manikins for thermo-physiological simulation of the human body

“…Ideally, a new-generation adaptive manikin should 'sense' and respond dynamically to the thermal environment as humans do. Forerunners of such systems have already been developed for evaluation of the comfort in vehicles (Farrington et al 2004), for testing clothing and sleeping systems (Blood and Burke 2010;Burke et al 2009;Psikuta et al 2008;Psikuta et al 2013;Redortier and Voelcker 2010) and for assessment of indoor microclimates (Foda and Siren 2012a;Foda and Siren 2012b;Nilsson 2004). All these attempts used various physical thermal devices and physiological models, and they were validated by comparison to the human thermal response obtained in dedicated human trials.…”

Initial Study on the State of the Art Solutions for the Simulation of the Thermoregulatory Sweating Conditions

“…The authors used following keywords for this operation: simulation, thermoregulatory, systems, sweating conditions, manikins and models of thermoregulation. After an intensive review, the materials with following reference number [1], [2], [3], [4], [5], [6] and [7], have been selected for further discussion. This choice criterion in particular was the holistic nature of approaches presented in found works.…”

“…3). The manikin does not only respond to thermal inputs such as radiation and convection it also affects the environmental flow field and temperature field [2]. It is a three-dimensional transient finite element model, contains a detailed simulation of human internal thermal physiological systems and thermoregulatory responses.…”

“…The manikin can be considered as surface sensor that measures the rate of heat loss at each surface zone. The main objective of the ADAM manikin and its model system is to predict the effect of thermal environments on human thermal physiology [2].…”

Using a Sweating Manikin, Controlled by a Human Physiological Model, to Evaluate Liquid Cooling Garments

“…The thermal comfort tools are composed of the manikin, the physiological control model, and the empirical thermal comfort model [15].…”