Permeability of Open-cell Foamed Materials

Permeability and Thermal Transport in Compressed Open-Celled Foams

“…The Hilyard and Collier model [5] is found to yield reasonable predictions of permeability for flow parallel to the direction of compression. A correction to the Gent and Rusch model [4] is proposed to better predict the permeability of flow in the direction transverse to the compression direction. Compression of foams increases the transverse heat transfer and reduces parallel heat transfer.…”

“…The normalized permeability of compressed foams from the experiments is compared in Figure 8 to numerical results from the present work for compressions less than the buckling compression (7.5%). The models of Gent and Rusch [4], Hilyard and Collier [5] and…”

Processing science: an approach for prepreg composite systems

“…The term LW is defined as the initiating compaction pressure: the pressure differential acting across the vacuum bag minus the vacuum pressure. The weight fraction resin will be given as i(t) = 1 -W(t) W(*) or (26) (tx) = 1 -w(t,x) w(*) Figure r illustrates the results of estimates of resin flow, Equations (22) - (24); and resin gradients, Equations (22), (23) and (26) (27) where M(L) is the moisture content in the prepreg received from the prepreger and h is half thickness of a ply or a laminate fOr two sided transfer. Although absorption for one ply is rapid as it is being layed up,very little moisture is lost from the stacked plies or laminate during the autoclave vacuum/temperature cycle.…”

“…This results because the laminate rests on a tool surface and can only desorb from the upper surface. The thickness h in Equation (27) is doubled. In addition, the total number of plies undergoing moisture transfer is 10, 100 or 400 versus one individual ply.…”

Permeability and Thermal Transport in Compressed Open-Celled Foams

“…Also, no effective parameters such as permeability were computed from the simulations. 4 The compressive behavior of metal foams is different from that of polyurethane foams. Kwon et al [9] showed that the mode of failure in metals is through plastic collapse at the joints, finally leading to complete collapse of the cell.…”