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El artículo aborda el problema de la práctica pedagógica de los docentes en formación desde la compleja relación entre teoría y práctica. Presenta cuatro formas de entender/establecer la relación entre teoría y práctica: 1) El componente didáctico; 2) La práctica como momento de utilizar la teoría; 3) La evaluación del cumplimiento de requisitos como la planeación, los diarios, la autobiografía y los registros; 4) El conocimiento que produce. Finalmente plantea la práctica pedagógica como un lugar privilegiado para la interacción comunicativa entre teoría y práctica a través de la experiencia docente en la cotidianidad educativa, cotidianidad que debe transformarse con el objetivo de reconstruir el saber pedagógico

The development of a global instability analysis code coupling a time-stepping approach, as applied to the solution of BiGlobal and TriGlobal instability analysis 1, 2 and finite-volume-based spatial discretization, as used in standard aerodynamics codes is presented. The key advantage of the time-stepping method over matrix-formulation approaches is that the former provides a solution to the computer-storage issues associated with the latter methodology. To-date both approaches are successfully in use to analyze instability in complex geometries, although their relative advantages have never been quantified. The ultimate goal of the present work is to address this issue in the context of spatial discretization schemes typically used in industry. The time-stepping approach of Chiba 3 has been implemented in conjunction with two direct numerical simulation algorithms, one based on the typically-used in this context high-order method and another based on low-order methods representative of those in common use in industry. The two codes have been validated with solutions of the BiGlobal EVP and it has been showed that small errors in the base flow do not have affect significantly the results. As a result, a three-dimensional compressible unsteady second-order code for global linear stability has been successfully developed based on finite-volume spatial discretization and time-stepping method with the ability to study complex geometries by means of unstructured and hybrid meshes.

Helical strakes are the most employed devices to mitigate or suppress vortex shedding behind circular cylinders. Although several investigations have been performed in order to predict the performance of these devices, proving its efficiency in specific configurations, little is understood regarding the physical mechanisms leading to the efficiency of these devices. The present work addresses this question from a global linear instability analysis point of view. Direct Numerical Simulation, three-dimensional global (TriGlobal) and Floquet stability analysis of the flow around a cylinder fitted with helical strakes is performed at low and moderate Reynolds number in order to understand more deeply the flow instabilities and physical mechanisms that mitigate and suppress the vortex-shedding.