TY - JOUR T1 - Extended Thermodynamic Approach for Non-Equilibrium Gas Flow JO - Communications in Computational Physics VL - 5 SP - 1330 EP - 1356 PY - 2013 DA - 2013/05 SN - 13 DO - http://doi.org/10.4208/cicp.301011.180512a UR - https://global-sci.org/intro/article_detail/cicp/7277.html KW - AB -

Gases in microfluidic structures or devices are often in a non-equilibrium state. The conventional thermodynamic models for fluids and heat transfer break down and the Navier-Stokes-Fourier equations are no longer accurate or valid. In this paper, the extended thermodynamic approach is employed to study the rarefied gas flow in microstructures, including the heat transfer between a parallel channel and pressure-driven Poiseuille flows through a parallel microchannel and circular microtube. The gas flow characteristics are studied and it is shown that the heat transfer in the non-equilibrium state no longer obeys the Fourier gradient transport law. In addition, the bimodal distribution of streamwise and spanwise velocity and temperature through a long circular microtube is captured for the first time.