Abstract
The entropy generation due to steady laminar forced convection fluid flow through parallel plates microchannel is investigated numerically. The effect of Knudsen, Reynolds, Prandtl, Eckert numbers and the nondimensional temperature difference on entropy generation within the microchannel is discussed. The fraction of the entropy generation due to heat transfer to the total entropy generation within the microchannel is studied in terms of Bejan number. The entropy generation within the microchannel is found to decrease as Knudsen number increases, and it is found to increase as Reynolds, Prandtl, Eckert numbers and the nondimensional temperature difference increase. The contribution of the viscous dissipation in the total entropy generation increases as Knudsen number increases over wide ranges of the flow controlling parameters.
Highlights
The entropy generation plays an important role in the design and development of thermo-fluid components such as heat exchangers, pumps, turbine, and pipe networks
Such high gradients are found in very small scale devices which interact with the fluid flow such as microchannels
Figure (7) shows that as Knudsen number increases, Bejan number decreases. This is attributed to the decrease in the temperature gradient as Knudsen number increases which in turns causes a decrease in the thermal part of the entropy generation and causes a decrease in Bejan number
Summary
The entropy generation plays an important role in the design and development of thermo-fluid components such as heat exchangers, pumps, turbine, and pipe networks. Figure (5) shows the development of the spatial fluid temperature distribution along the channel transverse direction and at different Knudsen numbers. Figure (6) shows the spatial distribution of the local entropy generation within the channel at different axial locations and for different values of Knudsen numbers.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have