The heat transfer and the fluid dynamics characteristics of subsonic gas flows through microchannels are examined using the direct simulation Monte Carlo (DSMC) method. A simple implicit treatment for the low-speed inflow and outflow boundaries for the DSMC of the flows in microelectromechanical systems (MEMS) is used. Micro-Couette flows and micro-Poiseuille flows are simulated with the value of the Knudsen numbers ranging between 0.06 and 0.72. Where appropriate, the calculated velocity slip and temperature distribution are compared with analytical solutions derived from the Navier-Stokes equations with slip-boundary conditions. A patterned microstructure with nonuniform surface temperature is also simulated. The computational results show that the Knudsen number and the geometric complexity have significant effects on the heat transfer as well as the fluid dynamics properties of the microfluid flows studied.

Issue Section:
Technical Papers
Keywords:
microfluidics, heat transfer, Knudsen flow, Couette flow, Poiseuille flow, channel flow, Monte Carlo methods, flow simulation, Channel Flow, Computational, Heat Transfer, Microscale, Monte Carlo
Topics:
Flow (Dynamics), Heat transfer, Temperature, Poiseuille flow, Simulation
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