Modelo simple para la permeabilidad dinámica de fluidos viscoelásticos

In the present work a simple form to obtain analytical expression for the dynamic permeability of Maxwellian fluids is presented. This expression gives the frequency dependent form of this dynamic permeability. In particular case, the analytic expression for the sinusoidal pressure pump fluid is illustrated in the configuration space. As an example of the feasibility of this expression the flow of human blood in a tube is presented finding that the human heart frequency has the same order that the frequencies where the dynamic permeability shows resonances. In order to make clear the above aspect of the dynamic permeability a model of pulsing pressure drops (gaussian like) are analyzed.

Preliminary evaluation of conceptual mechanical designs

Computational Design has traditionally required a great deal of geometrical and parametric data. This data can only be supplied at stages later than conceptual design, typically the detail stage, and design quality is given by some absolute fitness function. On the other hand, design evaluation offers a relative measure of design quality that requires only a sparse representation. Quality, in this case, is a measure of how well a design will complete its task.

The research intends to address the question: "Is it possible to evaluate a mechanical design at the conceptual design phase and be able to make some prediction of its quality?" Quality can be interpreted as success in the marketplace, success in performing the required task, or some other user requirement. This work aims to determine a minimum level of representation such that conceptual designs can be usefully evaluated without needing to capture detailed geometry. This representation will form the model for the conceptual designs that are being considered for evaluation. The method to be developed will be a case-based evaluation system, that uses a database of previous designs to support design exploration. The method will not be able to support novel design as case-based design implies the model topology must be fixed.