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941.
Roger Brown 《Polymer Testing》2013,32(8):1612
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An adaptive (Lagrangian) boundary element approach is proposed for the general three‐dimensional simulation of confined free‐surface Stokes flow. The method is stable as it includes remeshing capabilities of the deforming free surface and thus can handle large deformations. A simple algorithm is developed for mesh refinement of the deforming free‐surface mesh. Smooth transition between large and small elements is achieved without significant degradation of the aspect ratio of the elements in the mesh. Several flow problems are presented to illustrate the utility of the approach, particularly as encountered in polymer processing and rheology. These problems illustrate the transient nature of the flow during the processes of extrusion and thermoforming, the elongation of a fluid sample in an extensional rheometer, and the coating of a sphere. Surface tension effects are also explored. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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Roger A. Harris Michael Wilken Kai Fischer Trevor M. Letcher J. David Raal Deresh Ramjugernath 《Fluid Phase Equilibria》2007
High pressure vapor–liquid equilibrium data for binary systems of carbon dioxide with naphthalene and benzoic acid were measured at three different temperatures for each system. Experimental temperatures and pressures ranged from 373 to 458 K and 0 to 22 MPa, respectively. Dew points were also measured for naphthalene in the CO2 rich region. The data measured provides valuable solubility information and is used to derive gas–solvent group interaction parameters for the predictive Soave–Redlich–Kwong equation of state. 相似文献
948.
The task of fitting smoothing spline surfaces to meteorological data such as temperature or rainfall observations is computationally
intensive. The generalized cross validation (GCV) smoothing algorithm, if implemented using direct matrix techniques, is O(n
3) computationally, and memory requirements are O(n
2). Thus, for data sets larger than a few hundred observations, the algorithm is prohibitively slow. The core of the algorithm
consists of solving series of shifted linear systems, and iterative techniques have been used to lower the computational complexity
and facilitate implementation on a variety of supercomputer architectures. For large data sets though, the execution time
is still quite high. In this paper we describe a Lanczos based approach that avoids explicitly solving the linear systems
and dramatically reduces the amount of time required to fit surfaces to sets of data.
相似文献
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