Wicking, capillary

Development of a Capillary Wick Unsaturated Zone Pore Water Sampler... 

North, M.T., Shaubach R.M., Rosenfeld, J.H., Liquid Film Evaporation From Bidisperse Capillary Wicks in Heat Pipe Evaporators, Proceedings of 9" IHPC, May 1995, Albuquerque NM. 

C. P. Costello and E, R, Redeker, Boiling Heat Transfer and Maximum Heat Flux for a Surface With Coolant Supplied by Capillary Wicking, Chem. Eng. Prog. Symp. Ser. (59/41) 104-113,1963. 

C. P. Costello and W. J. Frea, The Role of Capillary Wicking and Surface Deposits in the Attainment of High Pool Boiling Burnout Heat Fluxes, AIChE J. (10) 393-398,1964. 

R. S. Gill, Pool Boiling in the Presence of Capillary Wicking Materials, SM thesis in mechanical engineering, Massachusetts Institute of Technology, Cambridge, MA, 1967. 

J. K. Ferrell and J. Alleavitch, Vaporization Heat Transfer in Capillary Wick Structures, preprint no. 6, ASME-AIChE Heat Transfer Conf., Minneapolis, MN, 1969. 

Surface forces tend to be inherently important for capillary-driven microfluidic devices as surface area-to-volume ratios are rather high and surface tension-induced interfacial curvature is significant enough to promote capillary wicking. For chemically patterned devices depending on hydrophobic/hydrophilic confinement in particular, the capillary number must be sufficiently low (i.e., Ca 1) in order to maintain fluid confinement within intricate geometry implying AF < ylw [1],... 

It is interesting to note here that the value of D is positive if a > 0q, which is equivalent to having a concave-free stuface. For a < 0q, on the other hand, no capillary wicking takes place. Equation 41 has been solved in the literamre [5] under various conditions. In the simple case of h (0,0 = ho, a similarity solution can be attempted with h(x, t) = ho4> ri), where rj= x/ y/Dt. An approximate solution, in that case, can be obtained as... 

The plasma treatment also reduced the water absorption of the composite by a factor of 3 and converted it from capillary (wicking along the fiber-matrix interface) to Pick s law absorption through the body of the matrix. The rate of water absorption in the composite was less than it was in a block of neat epoxy the same size as the composite. The difference in absorption rate was the same as the volume fraction of epo in the composite. This change in absorption mechanism would predict that there should be a great improvement in the hydrothermal stability of plasma treated composites. 

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