Pimentel's blog

Go to the first part:  On the irrationality (not irrotationality) of some "experts" (Part 1) During the re-election campaign last April-May, I made public a series of two articles, titled "On innovation and other hoaxes" *, available in both Spanish and Catalan on my alternative blog,  Blog de Pimentel  (with an accent on the last 'e'). In these articles, I exposed the arbitrary actions committed by both the former rector and the PhD doctoral coordinator, those who tried to cover up responsibilities and protect everyone involved in this situation.  The political dimension of the conflict became evident when the doctoral coordinator was surprisingly involved as a campaign coordinator for the former rector, while the former Doctoral School director, who held the position at the time of the events, was also a member of that electoral team . The first article aimed to detail the situation and the violations of internal university legislation. Following its publi...

VERSIÓN EN ESPAÑOL :  Sobre la irracionalidad de algunos “expertos” (Parte 1) 📝  Why I Once Called Myself a “Dummy” — And Why It Worked Two years ago, I wrote a blog post titled " Fluid dynamics for dummies, like me: on potential flows ". The title had a double intention: on one hand, I was being honest. I am just beginning my journey into the vast universe of aerodynamics and fluid dynamics, starting with the simplest case — incompressible flow. On the other hand, I wanted to poke a bit at a certain type of expert who dismisses Potential Flow Theory (PFT) as outdated or irrelevant. Some people didn’t appreciate the joke. Fig. 1 Potential flow solution for a parabolic parachute canopy (for added masses calculation; Pimentel, 2016). Note the clown face in the upper figure. One well‑known “potentialist” on LinkedIn took the title as a personal attack. Instead of reading and understand the intention of the article, he blocked me and criticized my writing style. Ironically, tha...

Go to the first part:  An 'inviscid' boundary layer! Is this a bug?! (Part 1) Approximately a year ago, I published the initial parts of a series detailing a significant visualization anomaly encountered within the Results module of ANSYS Workbench. I recently tested the newest ANSYS Student version (2025 R2) with the same 2D test case, and unfortunately, the issue persists despite having been reported in the official forum: a modeled boundary layer (BL) appears in the visualization for an inviscid flow simulation (over both an airfoil and a 3D wing; see Fig. 1). It is crucial to emphasize that this visual error does not appear in the ANSYS Fluent solver module. Since the solver correctly recognizes the inviscid condition (μ=0), it does not impose a no-slip condition at the wall, and thus, no BL is formed in the flow solution itself.  As those with a fundamental knowledge of fluid dynamics understand this is not a personal interpretation error, I believe this bug is primarily...