Sat, 05 Jul 2008 23:16:09 BST CiteULike: matthewhflamm's dispersion http://www.citeulike.org/user/matthewhflamm/tag/dispersion CiteULike.org en-gb Copyright © 2004-2008 citeulike.org http://www.citeulike.org/user/matthewhflamm/article/2870296 <i>Proceedings of the Royal Society of London. Series A, Mathematical and Physical Sciences, Vol. 235, No. 1200. (1956), pp. 67-77.</i><br /><br />Sir Geoffrey Taylor has recently discussed the dispersion of a solute under the simultaneous action of molecular diffusion and variation of the velocity of the solvent. A new basis for his analysis is presented here which removes the restrictions imposed on some of the parameters at the expense of describing the distribution of solute in terms of its moments in the direction of flow. It is shown that the rate of growth of the variance is proportional to the sum of the molecular diffusion coefficient, D, and the Taylor diffusion coefficient κ a2U2/D, where U is the mean velocity and a is a dimension characteristic of the cross-section of the tube. An expression for κ is given in the most general case, and it is shown that a finite distribution of solute tends to become normally distributed. On the Dispersion of a Solute in a Fluid Flowing through a Tube R Aris doi:10.2307/100013 Proceedings of the Royal Society of London. Series A, Mathematical and Physical Sciences, Vol. 235, No. 1200. (1956), pp. 67-77. 2008-06-06T19:32:28-00:00 1956 Proceedings of the Royal Society of London. Series A, Mathematical and Physical Sciences 235 1200 67 77 The Royal Society dispersion http://www.citeulike.org/user/matthewhflamm/article/2682995 <i>Biophys. J., Vol. 67, No. 3. (1 September 1994), pp. 1252-1259.</i><br /><br />Prior work has shown that concentration profiles of platelets in flowing whole blood and of platelet-sized beads in flowing blood suspensions can include near-wall excesses. A model to describe this phenomenon was built about a single-component convective diffusion equation. To incorporate redistribution to preferred sites by shear flows of red cell suspensions, the model used a drift shape function (in addition to the commonly used augmented diffusion coefficient). This paper reports experiments that provide an average concentration profile from which the shape function for that model is calculated; the experiments and shape function are for the particular conditions of 40% hematocrit, platelet-sized latex beads (2.5 microns diameter), tube ID of 217 microns, and a wall shear rate of 555 s-1. Less precise estimates of the shape function obtained from data of previous studies indicate that the shape function is similar for the hematocrit of 15%. An estimated shape function for drift in a platelet-transport model. C Yeh AC Calvez EC Eckstein Biophys. J., Vol. 67, No. 3. (1 September 1994), pp. 1252-1259. 2008-04-17T17:20:05-00:00 1994 Biophys. J. 67 3 1252 1259 convection dispersion platelet