Carlos Pimentel's blog

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 lift generation 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 micro level, 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 much lower viscosity valu

The recently developed Full Non-linear Vortex Tube-Vorton Method (FTVM) is a Lagrangian-based unsteady three-dimensional numerical method, that is, it does not require meshes to subdivide the space occupied by the flow, as Eulerian methods do in a more conventional computational fluid dynamics approach, for example, based on finite volumes. For this reason, it is less computationally expensive because, like all particle-based methods, it only requires calculating the flow variables at certain (and sufficient) points of interest and not in the entire surrounding space. In addition, the FTVM is based on a novel circulation-vorticity model, detached from the entire surface, which has recently been peer-reviewed and published in "Advances in Aerodynamics" Journal (Q1), owned by a world-renowned publishing house (Springer). In addition, the corresponding provisional patent was filed at the United States Patent and Trademark Office (USPTO) and recently extended to an international

Or to be more precise, how is the force that keeps them in the air generated? It is incredible that in the middle of the 21st century, where thousands of air vehicles fly across the globe daily, neither science nor engineering has been able to describe in detail the physical mechanism that causes the lifting 'force'*, which allows them to stay off the ground. Various hypotheses have been raised since the first flying apparatus took to the skies; however, none of these fulfill all aspects, and even the most reasonable ones remain debatable since they do not offer a general solution to all cases or flight conditions. Among the most widespread or well-known hypotheses, there is one that tries to explain that the lift 'force' is a consequence of the existing pressure difference between the lower and upper sides of a wing, related to 'Bernoulli's principle'; it has been colloquially called (perhaps disparagingly) “the explanation for pilots”, although, indeed, ev