Examples of Microchannel Mass Transfer Processes in Biological Systems

Heat and mass transfer processes become highly efficient as the channel hydraulic diameter is reduced in size. Biological systems, such as human body, rely on the extremely efficient transport processes occurring at microscale in the functioning of its vital organs. In this paper, the transfer processes in lungs and kidneys will be reviewed. Although the flow in the microchannels present in these organs is laminar, it yields very high mass transfer coefficients due to the coupling of small channel diameters. Furthermore, the molecular transport mechanisms occurring across the membranes at nanoscales through diffusion controlled processes also become extremely important. Understanding these transport processes will enable us to develop more efficient artificial organs and processes that closely mimic the performance of the natural systems. These ideas can be extended to other microscale system designs in different technologies, such as IC cooling and MEMS micro fuel cells.