Comparison of oxygen transfer in three types of gas exchangers : this thesis is submitted in partial fulfillment of requirements for the degree of Master of Science in Mathematics, School of Natural and Computational Sciences, Massey University, New Zealand

Abstract

The avian respiratory system is very different from that of mammals. In birds, air flows through the gas exchange area in one direction while in mammals it flows in two directions - in and out of the gas exchange area. It has been hypothesised that gas exchange occurs more efficiently in avian lungs than in mammalian lungs due to the difference in structure. We test this hypothesis by comparing oxygen exchange in three types of gas exchangers. First, we examine how gas exchange occurs in mammalian lungs, using a well-mixed stationary container of air with blood flowing along one axis. Next, we investigate the case where air flows in the opposite direction to the blood, which is similar to the gas exchange mechanism seen in fish. We then analyse how gas exchange occurs in the avian respiratory system, where the blood flow is perpendicular to the airflow. We compare the results under normal and extreme conditions and conclude that the avian respiratory system exhibits significantly higher gas exchange efficiency compared to mammals, ultimately enabling birds to live in environments where mammals could not survive.