A case study on development of thermodynamic entropy measuring device and its implication on the human body

Abstract

In the field of thermodynamics, entropy is a measure of the degree of disorder of the system considered focus. The direct measurement of entropy for microscopic systems involving molecule-level variations exists. However, for a macroscopic system, it still remains a challenge. The temperature reading is used as the primary index for understanding the quality of heat. In certain applications, the induced errors in the temperature measurement create complexity in decision making. One such case is the measurement of human body temperature for fever-like symptoms. This research aims to develop a direct entropy measuring device to indicate heat transfer for macroscopic systems. The developed device measured the mean entropy of the human body as 0.042 and 0.146 kJ/K during the daytime and nighttime, respectively. In comparison to the simulated entropy values, the measured values differed by 4% during the trials on the human body. Key decisions on macroscopic systems based on mild temperature variations can be made confidently with the measured entropy values.

Keywords

• Infrared
• Entropy measurement
• Body temperature
• Environment-induced errors
• Thermodynamics