About me

I am a human being and later an aeronautical engineer with experience mainly in experimental aerodynamics and computational fluid dynamics (CFD), trying to expose my perspective for a better understanding of fluid motion, confronted with concepts and knowledge that I personally consider wrong or even absurd. My research has been published as journal articles and I even have a patent pending. My philosophy is based on trying to understand the basics before going further; anything built on weak foundations will eventually collapse. I am not interested in learning things just for the sake of accumulating knowledge. To me, knowledge without application is nonsense. So I prefer to do other things instead, like practicing my favorite sport, walking around the city to get to know new places, listening to and discovering music, and tasting new foods. Knowledge comes in many ways, not just by reading books or sitting behind a desk.

"Fortunately, Science is not about what we want to believe, but about what we can prove". 



Designing, constructing and testing some toys at the National Polytechnic Institute, Mexico (2013).

Parachuting (not skydiving) in an Eastern European country (2014).

Ready for paragliding in Ager, Spain (2020).

Popular posts from this blog

Fluid dynamics for dummies, like me: on potential flows

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Potential Flow Theory (PFT) has always had a bad reputation among most fluidynamicist, among other things, because it is quite abstract and has only been successfully applied to explain, more or less, basic concepts of fluid dynamics, more specifically in aerodynamics, mainly through low-order numerical methods, such as panel ones, including the "well-known" vortex lattice method (VLM). Most lecturers teach during the fluid dynamics or computational aerodynamics courses that the PFT defines an irrotational (vorticity-free), incompressible (divergence-free) and inviscid (viscous-free) flow, which they call "ideal". However, its supposed inviscid characteristic is not theoretically defined and its current numerical implementation (including its attached circulation) is only a crude assumption! Such a misunderstanding can be demonstrated with a single image, from which it can be concluded that in fact, the current interpretation of the PFT has been used until now to
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On detached potential flow and the d'Alembert's paradox (September-2022)

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The Potential Flow Theory (PFT) states that a 'potential flow' must be incompressible (divergence-free) and irrotational (vorticity-free). However, compressible potential flow also exists, but it is not defined within the classical PFT. Then, strictly and in a broader sense, a potential flow must only fulfill the irrotationality condition. At this point, the term 'viscosity' is absent from such a definition, however, for the same reason that such a term does not appear, the fluid-flow viscosity value can be considered zero. Then, an 'inviscid potential flow' is now called an 'ideal flow' in order to be more specific. However, from the current interpretation, a viscous-forced potential flow (Kutta-Zhukovski-type pseudo- real flow) can also be defined, hence, 'potential flow' is not a synonym of ideal flow, as most authors misunderstand. In other words, the ideal flow is a potential flow, but a potential flow is not necessarily the ideal flow
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Could there be lift without viscosity?

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One of the classic debates in aerodynamics (or fluid dynamics, in general) is whether the existence of viscosity in a fluid is an essential condition for the generation of lift 'force' in an immersed body. First, the concept of viscosity must be explained, which is a property that is closely related to the physical constitution of the fluid at a microlevel, that is, at the molecular scale. Thus, this can be understood as the level of resistance or friction that its "particles" oppose to the displacement of their neighbors in the tangential direction (with respect to the flow), and that depends on the time it takes for the particles of an 'upper layer' to fill the spaces left in a 'bottom layer' (relative to a 'solid wall') as the fluid flows. Fig. 1 CASA-295 aircraft CFD simulation (just to get your attention!). To put it in context, a typical example of a fluid with a high viscosity is honey, which moves more slowly than water, which has a muc
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