A Numerical Analysis of the Fiber Web Effects on the Pressure Drop, Particles Collection, and Heat Transfer in a MicroChannel

摘要

In this paper, pressure drop, heat transfer characteristics, and particle deposition in a microchannel with a fiber web at the inlet are investigated numerically. The fiber web was made up of fibers several hundred micrometers in length caught at the entrance of the channels. Governing equations for the flow field are solved by an Eulerian approach, while the equations of particle motion in the flow are solved by a Lagrangian approach. Assuming the symmetry in the domain, one channel and the corresponding inlet and outlet plenums are selected as the computational domain. Several fiber webs with various fiber numbers, orientations, and dimensions are modeled. The increase in the pressure drop and the decrease of heat transfer due to the fiber web are computed and discussed. A correlation is developed for pressure drop as a function of the fiber web blockage ratio, microchannel geometry, and flow characteristics. The deposition of the microparticles with various diameters on the fiber webs is investigated, as well. Deposition of the particles on the fiber web is because of two different mechanisms, inertial impaction and interception. The numerical results indicate that the fiber webs have no considerable effect on the heat transfer characteristic of the channel under constant pumping power.