Experimental and numerical study of physiological responses in hot environments

Area of Science:

• Environmental Science
• Human Physiology
• Thermal Engineering

Background:

• Understanding human thermal responses is vital for designing safe and comfortable environments.
• Existing models require refinement to accurately predict physiological changes under extreme heat.
• Tanabe's model provides a foundation for further development in heat exchange analysis.

Purpose of the Study:

• To propose and validate an extended multi-node human thermal model.
• To investigate the impact of high temperatures on human heat production and blood flow.
• To accurately predict skin and core temperatures in diverse thermal conditions.

Main Methods:

• An extended multi-node human thermal model was developed, incorporating high-temperature effects on heat production, blood flow, and heat exchange.
• Experimental validation involved five healthy men exposed to thermal neutral (29°C) and high-temperature (45°C) environments.
• Continuous measurement of rectal and skin temperatures across seven body segments was performed.

Main Results:

• The model demonstrated high accuracy in predicting both the tendency and absolute values of skin and core temperatures.
• Temperature prediction errors were generally smaller in the high-temperature environment compared to the neutral environment for most body segments.
• The model successfully predicted human physiological responses in hot environments.

Conclusions:

• The extended multi-node human thermal model accurately predicts human thermal responses in hot conditions.
• The model's enhanced consideration of heat exchange coefficients and physiological parameters improves prediction accuracy.
• This validated model is a valuable tool for thermal comfort and safety assessments in extreme heat.