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Experimental Methods for Investigation of Shape Memory Based Elastocaloric Cooling Processes and Model Validation
Published on: May 2, 2016
Model of human/liquid cooling garment interaction for space suit automatic thermal control
K L Nyberg1, K R Diller, E H Wissler
1Department of Mechanical Engineering,The University of Texas at Austin, 78712, USA.
Journal of Biomechanical Engineering
|March 30, 2001
Summary
This study enhanced a human thermoregulation model to simulate space suit thermal control, improving astronaut comfort during extravehicular activity (EVA). The advanced model accurately predicted thermal interactions and controller performance.
Area of Science:
- Spacecraft thermal control systems
- Human physiological modeling
- Biomedical engineering
Background:
- Astronaut thermal comfort is critical for mission success and performance during extravehicular activities (EVA).
- Existing human thermoregulation models require enhancement to accurately simulate the complex thermal interactions within space suits.
- Liquid cooling garments (LCGs) are essential for managing astronaut heat loads during EVA.
Purpose of the Study:
- To augment the Wissler human thermoregulation model for simulating space suit thermal control systems, including LCGs and ventilation.
- To aid in the design of an automatic controller for maintaining thermal neutrality in exercising astronauts wearing LCGs.
- To evaluate the efficacy of physiological measurements for real-time feedback in the control algorithm.
Main Methods:
- Augmented the Wissler human thermoregulation model to include space suit thermal control, LCG, and ventilation.
- Designed and built an experimental apparatus to test physiological feedback for an automatic control algorithm.
- Conducted experiments in a simulated space suit environment with varying metabolic loads and environmental temperatures.
Main Results:
- Simulations accurately predicted thermal interactions between subjects and LCGs across diverse metabolic profiles and environmental conditions.
- The augmented model accurately reflected the performance of the automatic temperature controller for LCG coolant.
- Experimental evaluations validated the control algorithm's efficacy in maintaining thermal comfort during simulated EVA.
Conclusions:
- The enhanced Wissler model provides a robust tool for designing and evaluating space suit thermal control systems.
- The developed automatic control system effectively maintains astronaut thermal comfort during demanding extravehicular activities.
- This research contributes to improving astronaut safety and performance in future space missions.
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