Ingeniería Mecánica Tecnología y Desarrollo

Integration of Evolutionary Algorithms and CFD for Performance Optimization in PEMFCs

Evelin J Sanchez-Rodriguez — 2025-09-24

In Proton Exchange Membrane Fuel Cells (PEMFC), the membrane critically influences the proton transport efficiency and water management, directly impacting the overall cell performance. This study develops an advanced computational methodology combining evolutionary algorithms (CMA-ES) with CFD simulations to optimize membrane thickness in PEMFC. The optimization approach achieves a 23% increase in power density while reducing ohmic resistance by 32% and improving water content uniformity by 18% compared to the base case. The coupled CFD-Optimization methodology establishes a new paradigm for simulation-driven fuel cell design, demonstrating significant improvements for automotive applications where power density and water management are crucial.

Shear testing of complex geometry specimens

Jorge Luis Flores Alarcón — 2025-09-26

This work studies a pure shear test using an innovative probe geometry in AA6016 sheet, which is a commercial alternative to steel in the automotive industry. The analysis of anisotropic plastic deformation is performed by two contrasting techniques: the simulation uses a software that follows the texture evolution during the simulation, and takes into account the material interaction during the deformation of neighboring grains, to update the deformation texture, while the experiments are analyzed by digital image correlation, which uses a series of video stills of the sample during deformation and calculates the displacement fields and deformations. The results show that the simulation reproduces the test considering ideal conditions of pure shear, which contrasts with the experiment, where pure shear only occurs for the initial displacements. Texture measurements obtained confirm shear components in the shear region.

Importance of heat pumps with double absorption process

Tabai Torres Díaz — 2025-09-30

Energy administration is one of the most pressing challenges of this century due to it has an impact on geopolitical, economic, and environmental aspects. This study shows a theoretical analysis of a heat pump with a double absorption process and LiBr/H₂O for simultaneous cooling and heating. In the thermodynamic analysis, the first law of thermodynamics is applied to evaluate the individual and overall coefficients of performance, considering waste heat temperatures ranging from 70 to 90 °C. An overall coefficient of performance of 0.786 is achieved with cooling and heating temperatures of 14 and 110 °C, respectively, using a waste heat temperature of 80 °C and low and high-pressure evaporators of 5 and 1 kW, respectively.

Analysis of the kinematic effect of mobile phone use on human gait

Hugo Iván Medellín-Castillo — 2025-09-29

Cell phones (CP) have become an essential part of our daily lives; however, although the CP use is associated with an increase in musculoskeletal injuries during gait, few research works have quantified their effect on the gait pattern. Therefore, a research need is identified to investigate the effect of CP use during human gait of Latin people. In this work, a study to evaluate the kinematic effect of CP use during gait, is presented. The aim is to evaluate the kinematic variations of the human gait patterns under CP use, and compare them with the gait patterns without CP use. For this purpose, several gait experiments were performed on a walkway under different CP usage conditions (DCPC). From these experiments, the main kinematic parameters of gait were determined using computer vision techniques. The results show that the human gait pattern varies with the CP usage, having the largest variation when walking while writing and reading text messages.

Correlation Between Microstructural Characteristics and Stress Corrosion Cracking in API 5L Steels

D. González-Fong — 2025-09-30

The study evaluates the effect of microstructural characteristics in pipeline-grade steels on their susceptibility to stress corrosion cracking (SCC) in near-neutral pH environments, by using pipe segments with API 5L X56 and X60 specifications. Experimental methodology includes immersing the specimens in NS4 solution and using a three-point bending setup to simulate operating conditions. Results show pitting with atypical morphology, and photographic evidence reveals transgranular cracks associated with the SCC phenomenon. Also, it was observed that microstructural homogeneity and a higher content of pearlitic microconstituents reduce pit formation; likewise, the results demonstrate that pit formation depends on the magnitude of the applied stress.