A COMPARATIVE STUDY ON THE ENTROPY GENERATION IN THE HUMAN RESPIRATORY TRACT BASED ON HESS-MURRAY LAW AND WEIBEL EXPERIMENTED RESULT

Entropy generation (S-gen) is associated with the irreversibility of any thermodynamic system. It provides an indication of lost energy of a system. The main objective of this study is to show a method for calculating entropy generation in the human respiratory tract. In this work, human respiratory tract geometries from two different approaches are considered, first one is based on Hess-Murray theory and the second one is based on Weibel's experimented result. The entropy generation has been calculated considering duct wall friction along with effect of bifurcation and diffusion. In this study, two different physiological conditions have been contemplated, i.e., at rest and at heavy physiological activities. It has shown that S-gen of human respiratory is lowest at 23rd level of bifurcation. The outcome of the study reveals that the entropy generation rates per day based on Hess-Murray theory at rest and under heavy physiological activities are 8.42 x 10(-5) kJ/K and 0.013 kJ/K, whereas the same based on Weibel's experimented result at rest and under heavy physiological activities are 0.221 x 10(-3) kJ/K and 0.05 kJ/K, respectively.