Abstract:
It is well known that oscillating flow can increase heat
transfer over steady-state flow. Inserting porous media in the
path of a flow also enhances convection heat transfer.
Combining these two effects (oscillating flow and porous media)
is supposed to substantially augment heat transfer. In order to
understand the heat transfer in such arrangement, one must first
understand the flow behavior. Oscillating water flow in open-cell
metal foam having 10 pores per inch (ppi) has not been reported
in the literature. In this paper, main characteristics of oscillating
water flow in 10-ppi open-cell metal foam is reported. The foam
had a porosity of 87%. Three flow displacements 74.3, 97.2 and
111.5 mm were applied at the relatively high flow frequencies of
0.46, 0.58 and 0.69 Hz. The effect of flow displacement and
frequency on important parameter is presented and discussed.
The appropriately defined friction factor correlated well with the
kinetic Reynolds number. Steady-state experiments were also
conducted for Darcy and Forchheimer water flow through the
same metal foam, and the permeability and form/inertial drag
coefficient were obtained. Comparisons of the friction factor for
oscillating and steady flows is presented. The results of this study
are very likely applicable to similar foam-like highly porous
media, and is critical for interpreting oscillating heat transfer in
metal foam.
Description:
Papers presented to the 12th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Costa de Sol, Spain on 11-13 July 2016.
