Performance analysis of human cardiorespiratory system based on the second law of thermodynamics
by Abhijit Dutta; Himadri Chattopadhyay
International Journal of Exergy (IJEX), Vol. 34, No. 1, 2021

Abstract: This work presents a thermodynamic model of the human cardiorespiratory system under different physiological conditions based on the second law of thermodynamics. The analysis reports three different physiological conditions i.e., rest, moderate level of physical activity and extreme level of physical activity. Human cardiorespiratory performance is found to increase significantly with the increase in physical activity. However, the cardiorespiratory performance also notably increases with the increase in ambient temperature and RH. The cardiomegaly condition of the cardiorespiratory system decreases the efficiency of the system. Results show that O2 fluctuation for metabolic use has no significant effect on the human cardiorespiratory performance. A new dimensionless number, which is the ratio of breathing rate to the heart rate (BHR), is introduced in this work. The present work reveals that the thermodynamic performance of the cardiorespiratory system depends on the inhaled air property (temperature and RH), cardiomegaly condition and the variation of BHR.

Online publication date: Wed, 23-Dec-2020

The full text of this article is only available to individual subscribers or to users at subscribing institutions.

Existing subscribers:
Go to Inderscience Online Journals to access the Full Text of this article.

Pay per view:
If you are not a subscriber and you just want to read the full contents of this article, buy online access here.

Complimentary Subscribers, Editors or Members of the Editorial Board of the International Journal of Exergy (IJEX):
Login with your Inderscience username and password:

    Username:        Password:         

Forgotten your password?

Want to subscribe?
A subscription gives you complete access to all articles in the current issue, as well as to all articles in the previous three years (where applicable). See our Orders page to subscribe.

If you still need assistance, please email