The present study focuses on the numerical simulation of unsteady cavitating flow around a plane-convex hydrofoil with a semi-cylindrical obstacle, which is based on the cavitation-erosion experiment perform at LMH-EPFL using the vortex cavitation generator tunnel. The turbulence model k-ω SST SAS method, which presents advantages in terms of computational consumption and reproduction of the phenomenon, has been applied in OpenFOAM version 4 to reproduce the unsteady behavior of cavitating flow. Additionally, the Zwart-Gerber-Belamri (ZGB) cavitation model has been applied, based on a previous work where this model was implemented in OpenFOAM. The model is based on Rayleigh Plesset equation, which considers small cavities with changes of void fraction for condensation and vaporization and using empirical calibration numbers based on previous research. Regarding the mesh development, the present work explores two configurations of grid mesh containing hexahedra (hex) and split-hexahedra (split-hex) automatically generated from triangulated surface geometries based on previous numerical studies. The aforementioned method aims to optimize computational demand and phenomenon reproducibility. Results show that the unsteady cavitating flows behavior has been reproduced with good accuracy and shows special details which are important for erosion studies in futures works.

The objective of this work is to use the autonomous learning methodology as a tool in vehicle maintenance management. In obtaining data, faults in the fuel supply system have been simulated, causing anomalies in the combustion process that are easily detectable by vibrations obtained from a sensor in the engine of an agricultural tractor. To train the classification algorithm, 4 engine states were used: BE (optimal state), MEF1, MEF2, MEF3 (simulated failures). The applied autonomous learning is of the supervised type, where the samples were initially characterized and labeled to create a database for the execution of the training. The results show that the training carried out within the classification algorithm has an efficiency greater than 90%, which indicates that the method used is applicable in the management of vehicle maintenance to predict failures in engine operation.

En el presente trabajo se produjo bioetanol a partir de residuos de maíz en la provincia de Imbabura-Ecuador. Se ha utilizado los residuos del maíz específicamente del tipo “Zea mays l” (Chaucho Mejorado) que se produce en la provincia de Imbabura. Se determinó su factibilidad en cuanto a su posible producción en términos de biomasa disponible. Se ha caracterizado el etanol en una mezcla E10 es decir 10% de etanol y 90% de Gasolina Súper, para determinar su factibilidad en su uso para el motor como combustible, teniendo resultados satisfactorios.

The present study has the purpose of determining the levels of opacity with the use of diesel and biodiesel based on castor oil at 15\% (B15). For the determination of the opacity an electronic diesel engine test bench was used, the opacity measurements were made using a duly calibrated opacimeter. The Opacimeter consists of a probe which is installed at the end of the exhaust pipe, capturing the gases and yielding their own values for each test, considering the types of fossil fuel or biofuel and engine speed, subjecting several RPMs that go from 1200 to 3000 for each fuel. At the end of the tests, the opacimeter allowed to obtain an opacity of 11.1\% with fossil diesel and 0.386 with B15, obtaining a 96\% reduction in opacity. At the same time, an average opacity of the tests was obtained for each type of fuel, this value being compared with the national standards concerning this study. With these results, it contributes to the conservation of the environment since it emits less amount of soot, in the same way, the respiratory and heart diseases of people are reduced according to the world health organization.