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  • PublicationOpen Access
    Maximum attenuation variability of isotropic magnetosensitive elastomers
    (Elsevier, 2016-07-14) Agirre Olabide, Iker; Elejabarrieta, María Jesús; Ingeniería; Ingeniaritza
    Magnetosensitive elastomers (MSE) are innovative high-tech materials that exhibit changed dynamic properties when an external magnetic field is applied. In this work, the influence of particle content, frequency, temperature and magnetic field on the maximum attenuation of isotropic MSEs was studied. Six particle content types were synthesised using carbonyl iron powder particles embedded in a room-temperature vulcanizing silicone rubber matrix. The characterization of the MSE samples was performed with a Physica MCR 501 rheometer from the Anton Paar Company that is equipped with a magnetorheological cell. All samples were characterized using frequency sweep tests within the lineal viscoelastic region. In addition, a four-parameter fractional derivative model was used and extended over a wide frequency range. The influence of temperature was modelled using the Arrhenius model, coupled with the fractional derivative model. The maximum attenuation is increased with frequency and magnetic field and is independent of temperature.
  • PublicationOpen Access
    Matrix dependence of the linear viscoelastic region in magnetorheological elastomers
    (SAGE, 2015-04-21) Agirre Olabide, Iker; Elejabarrieta, María Jesús; Bou-Ali, M. Mounir; Ingeniería; Ingeniaritza
    The aim of this work is to study the linear viscoelastic region limit of isotropic magnetorheological elastomers at different compositions and working conditions. Regarding the synthesis process, the matrix and the particle content are analysed. The analysed matrixes are a natural rubber, a silicone rubber and ELASTOSIL® silicone, and three particle contents are synthesised. The influence of the characterisation variables on the linear viscoelastic limit, that is, frequency, external magnetic field and temperature, is also analysed. Strain sweep tests are used to determine the dynamic complex modulus. The loss factor and the storage modulus are analysed to define the linear viscoelastic limit of each isotropic magnetorheological elastomer sample in all the working conditions. The results show that the linear viscoelastic region of the magnetorheological elastomers is defined by the loss factor. Moreover, the volumetric particle content reduces and frequency increases the linear viscoelastic region of all the matrixes, whereas the external magnetic field and the temperature influences are matrix dependent.
  • PublicationOpen Access
    Characterization of the linear viscoelastic region of magnetorheological elastomers
    (SAGE, 2014-01-13) Agirre Olabide, Iker; Berasategui, Joanes; Elejabarrieta, María Jesús; Bou-Ali, M. Mounir; Ingeniería; Ingeniaritza
    The linear viscoelastic behaviour of magnetorheological elastomers is analysed in this work according to their formulation and working conditions. This study comprised both the synthesis of different magnetorheological elastomers and the strain and frequency sweep characterization under different magnetic fields and temperatures. The characterization was performed by a Physica MCR 501 rheometer from Anton Paar, equipped with a magnetorheologic cell 70/1T MRD. In the synthesis with a given elastomeric matrix, samples with different magnetic particle content are studied with two types of curing conditions: under the action of a magnetic field (anisotropic magnetorheological elastomers) and without a magnetic field (isotropic magnetorheological elastomers). The working conditions are excitation frequency, temperature and the applied external magnetic field. In this work, a new procedure to determine the linear viscoelastic behaviour is proposed; the loss factor is analysed in addition to analysing the storage modulus to determine the linear viscoelastic region of each sample. The results show that high temperatures and magnetorheological elastomers with higher volume fraction of magnetic particles restrict the linear viscoelastic behaviour of magnetorheological elastomers.
  • PublicationOpen Access
    Compression and torsion testing for elastic moduli and Poisson's ratio characterization in silicone rubber samples with varying shape factors
    (Elsevier, 2025-05-19) Cortazar-Noguerol, Julen; Cortés, Fernando; Agirre Olabide, Iker; Elejabarrieta, María Jesús; Ingeniería; Ingeniaritza
    Elastomeric materials, such as silicone rubber, are widely used in engineering applications due to their high deformability and viscoelastic properties. Under quasistatic regime and small deformations their behavior can be considered purely elastic and can be characterized by the elastic modulus, shear modulus, and Poisson's ratio, which are interrelated in isotropic materials. Although standard methodologies exist for determining these properties, experimental measurements are known to be affected by the geometry of the tested samples. The influence of sample geometry on compressive modulus measurements is well understood, however, its effect on shear modulus measurements is less explored. This study investigates how the dimensions of cylindrical samples influence the experimental determination of both the compressive and shear moduli and, consequently, Poisson's ratio. Compression and torsion tests are performed on silicone rubber samples of varying diameters and lengths using a dynamic mechanical analyzer and a rheometer respectively. The results confirm that both the compressive and shear moduli are affected by sample geometry, leading to unrealistic values of Poisson's ratio. To account for these effects, a correction model is proposed for shear modulus measurements, complementing existing corrections for compressive tests. The model successfully describes experimental trends and provides a more reliable estimation of Poisson's ratio, aligning with theoretical expectations for nearly incompressible elastomers. These findings emphasize the importance of considering geometric effects in compressive and torsion tests and provide a framework for improving the accuracy of mechanical characterization in elastomeric materials.
  • PublicationOpen Access
    High fidelity CFD models comparison to potential flow method in the simulation of full scale floating platform under free decay tests
    (Elsevier, 2025-05-01) Gil Liberal, Miguel; Armañanzas Goñi, Javier; Torres Salcedo, Alexia; Fuertes Bonel, Juan Pablo; Campaña, Guillén; Méndez López, Beatriz; León Iriarte, Javier; Ingeniería; Ingeniaritza; Institute of Smart Cities - ISC; Gobierno de Navarra / Nafarroako Gobernua
    The use of simulation models based on potential flow is widespread in the wind industry for the simulation of floating wind turbines. However, these analytical models have shortcomings in correctly representing the behavior of Floating Offshore Wind Turbines (FOWTs) under extreme wind and wave conditions. High fidelity Computational Fluid Dynamics (CFD) simulations aim to develop models where the fluid-structure interaction is more accurately modeled, allowing to correctly predict the behavior of wind turbines and thus to redesign structural components and save costs. In this paper, two different CFD simulation models are developed and compared, including different turbulence models (Reynolds-Averaged Navier-Stokes (RANS) and Large Eddy Simulation (LES)), numerical methodologies (Navier-Stokes and Lattice-Boltzmann method) and mooring models (Quasi-Static and Dynamic). Different free decay Load Cases (LC) are performed in XFlow and OpenFOAM, and the damping ratio and natural period of the system are analyzed with different mooring arrangements (Multi-Point Mooring (MPM) and Single-Point Mooring (SPM)), comparing all results with respect to a potential flow model (HydroDyn). A maximum error of 3.3 % in natural period and 1.6 % error in damping factor is obtained, small enough to validate the results of CFD models. Vorticity is also analyzed to understand the differences between both CFD models. Finally, the stress of the mooring lines is computed, which allows validating the mooring system model implemented in XFlow by means of external functions.
  • PublicationOpen Access
    Optimization and modeling of ZrB2 ceramic processing by EDM for high-performance industrial applications
    (Elsevier, 2025-04-11) Luis Pérez, Carmelo Javier; Torres Salcedo, Alexia; Puertas Arbizu, Ignacio; Ingeniería; Ingeniaritza; Institute for Advanced Materials and Mathematics - INAMAT2
    This study investigates the Electrical Discharge Machining (EDM) of zirconium diboride (ZrB2), a novel conductive ceramic with exceptional properties, including high temperature resistance, excellent thermal conductivity, and remarkable hardness. These properties make ZrB2 highly suitable for extreme environments, such as aerospace and nuclear applications. To the best of our knowledge, no comprehensive studies have addressed the manufacturing of ZrB2 parts by EDM, positioning this research as a cutting-edge contribution. Two electrode materials, graphite (C) and copper-graphite (Cu–C), were used to analyze the material removal rate (MRR) and surface roughness (Ra) as functions of current intensity (I), pulse time (ti), and duty cycle (η). Multiple Linear Regression (MLR) and Artificial Neural Networks (ANN) were used to model the response variables. While MLR was effective for MRR (R2 > 0.9), ANN outperformed it in predicting Ra, especially for Cu–C electrodes (R2 = 0.9366 vs. 0.3847 for MLR). Current intensity was the most influential parameter for MRR, while pulse time significantly affected Ra. Residual analysis confirmed ANN superior accuracy for Ra, with residuals below ±1 vs. ±2 for MLR. The study culminated in the successful EDM manufacture of a ZrB2 hexagonal nut, employing optimized parameters (I = 6 A, ti = 50 μs, η = 0.3, for the C electrode) derived using ANN models and particle swarm optimization. This result demonstrates the EDM process ability to produce high-precision components with complex geometries, showcasing its versatility and industrial potential. Therefore, this study broadens the understanding of ZrB2 machinability and expands its applications in advanced technologies.
  • PublicationEmbargo
    Compensation strategy to minimize over-cut effects in robotic belt grinding with passive-compliant tools
    (Elsevier, 2025-03-19) Torres Izu, Ramón; Iriarte Goñi, Xabier; Mata Cantón, Sara; Aginaga García, Jokin; Barrenetxea Azpeitia, David; Ingeniería; Ingeniaritza; Institute of Smart Cities - ISC; Gobierno de Navarra / Nafarroako Gobernua
    At the beginning of the robotic belt grinding path, passive-compliant tools can generate an over-cut effect. The transient state from the first contact point between tool and workpiece to the grinding steady state can generate an excess of material removal at the workpiece border. If successive grinding passes are made, this effect will accumulate, increasing the shape deviation at the workpiece border. Therefore, the purpose of this research is to analyze this phenomenon and develop an easy-to-implement compensation strategy to avoid removing an excess of material at the beginning of grinding paths. Specifically, a geometric model of the contact has been developed that, together with the material removal model, allows to reproduce the cut-in effect for a robot-operated passive-compliant tool case. In turn, the compensation strategy that has been designed, avoids removing an excessive amount of material by means of a cut-in path that adjusts the feed velocity to the instantaneous contact force. This path is based on the tool geometry and grinding process parameters. In order to validate the proposed strategy, several experiments have been performed for different process conditions. Results show how the proposed solution significantly reduces the over-cut effect providing a homogeneous material removal since the beginning of the grinding.
  • PublicationEmbargo
    Predicting the spatial distribution of reducing sugars using near-infrared hyperspectral imaging and chemometrics: a study in multiple potato genotypes
    (Elsevier, 2025-03-27) Peraza Alemán, Carlos Miguel; Arazuri Garín, Silvia; Jarén Ceballos, Carmen; Ruiz de Galarreta, José Ignacio; Barandalla, Leire; López Maestresalas, Ainara; Ingeniería; Ingeniaritza; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD
    The determination of reducing sugars in potatoes is important due to their impact on product quality during industrial processing. The significant variability of these compounds between genotypes presents a challenge to the development of accurate predictive models. This study evaluated the potential of near-infrared hyperspectral imaging (NIR-HSI) for the prediction of reducing sugars in potatoes. For this, a wide range of genotypes (n=92) from two seasons (2020-2021) was selected. Partial Least Squares Regression (PLSR) and Support Vector Machine Regression (SVMR) methods were used to build the prediction models. Furthermore, interval PLS (iPLS), recursive weighted PLS (rPLS), Genetic Algorithm (GA) and Competitive Adaptive Reweighted Sampling (CARS) were used for relevant wavelength identification to develop less computationally complex models. The best full spectrum model (SNV-PLSR) achieved coefficient of determination and root mean square error values of 0.88 and 0.053% and 0.86 and 0.057%, for calibration and external validation, respectively. Variable selection algorithms successfully reduced the dimensionality of the data without compromising the performance of the models. Robust predicted models were built with only 2.65% (CARS-PLSR) and 3.57% (iPLS-SVMR) of the total wavelengths. Finally, a pixel-wise prediction was performed on the validation set and chemical images were built to visualise the spatial distribution of reducing sugars. This study demonstrated that NIR-HSI is a feasible technique for predicting reducing sugars in several potato genotypes.
  • PublicationOpen Access
    Análisis espacio-temporal de los accidentes mortales con tractor en España durante el período 2010-2019
    (Interempresas Media, 2023) Arazuri Garín, Silvia; Ibarrola, Alicia; Mangado Ederra, Jesús; Adin Urtasun, Aritz; Arnal Atarés, Pedro; López Maestresalas, Ainara; Jarén Ceballos, Carmen; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Ingeniería; Ingeniaritza
    El sector agrario y el de la construcción son los que presentan los índices de incidencia de accidentes de trabajo mortales más altos de nuestro país, según los datos recogidos por el Instituto Nacional de Seguridad y Salud en el Trabajo (INSST) (2021) dependiente del Ministerio de Trabajo y Economía Social (Cirauqui, 2022). Si tenemos en cuenta la evolución de estos índices, el sector agrario es el único que no ha mejorado dicho índice desde la aparición de la Ley 31/1995 de prevención de riesgos laborales y su siniestralidad continúa aumentando (Fundación Mapfre 2020). Pero, ¿qué ocurre cuando el accidente lo sufren personas que no encajan en la definición legal de trabajador? Estos accidentes no son considerados 'accidente de trabajo' y, por tanto, escapan a todas las estadísticas y datos oficiales del INSST. Este suele ser el caso de muchos accidentes que sufren personas jubiladas, menores de 16 años, familiares colaboradores, etc. que no son personas vinculadas a la actividad laboral tal y como se define en la legislación. Según Arana et al. (2010) de un total de 388 accidentes mortales ocurridos en España con maquinaria agrícola durante los años 2004-2008, solamente el 61,85% de ellos tuvieron carácter oficial. Las personas mayores fueron el sector de la población con un mayor riesgo, seguidos de los niños y las personas ajenas al sector agrario. La mayoría de las muertes fueron debidas al vuelco de tractores sin estructuras de protección.
  • PublicationOpen Access
    Análisis de la siniestralidad por vuelco de tractor en el período 2017-2021
    (Interempresas Media, 2023) Casuso, G.; Arazuri Garín, Silvia; Mangado Ederra, Jesús; López Maestresalas, Ainara; Arnal Atarés, Pedro; Jarén Ceballos, Carmen; Ingeniería; Ingeniaritza; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD
    Desde que en 1995 se promulgó la Ley 31/1995 (BOE nº269/1995) de Prevención de Riesgos Laborales se ha observado una disminución importante de la siniestralidad laboral en todos los sectores. Sin embargo, en el sector agrario esta disminución no ha sido del calado de otros sectores y, por ejemplo, los índices de mortalidad prácticamente se mantienen en el tiempo. Tal es así, que el sector agrario ha sido calificado por el Observatorio Estatal de Condiciones de Trabajo (OECT) como prioritario para el desarrollo de políticas preventivas eficientes que permitan reducir la siniestralidad en el sector en base al índice de accidentes graves y mortales ajustado por la población afiliada.
  • PublicationEmbargo
    Mapping acrylamide content in potato chips using near-infrared hyperspectral imaging and chemometrics
    (Elsevier, 2025-03-14) Peraza Alemán, Carlos Miguel; López Maestresalas, Ainara; Jarén Ceballos, Carmen; Ruiz de Galarreta, José Ignacio; Barandalla, Leire; Arazuri Garín, Silvia; Ingeniería; Ingeniaritza; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD
    This study investigated the potential of near-infrared hyperspectral imaging (NIR-HSI) for the prediction of acrylamide content in potato chips. A total of 300 tubers from two potato varieties (Agria and Jaerla) grown in two seasons and processed under the same frying conditions were analysed. Partial Least Square Regression (PLSR) and Support Vector Machine Regression (SVMR), combined with a logarithmic transformation of the acrylamide levels, were applied to develop predictive models. The most optimal outcomes for PLSR yielded R2 p: 0.85, RMSEP: 201 μg/kg and RPD: 2.53, while for SVMR yielded R2 p: 0.80, RMSEP: 229 μg/kg and RPD: 2.22. Furthermore, the selection of significant wavelengths enabled an 87.95 % reduction in variables without affecting the model’s accuracy. Finally, spatial mapping of acrylamide content was conducted on all chips in the external validation set. This method provides both quantification and visualization capabilities, thus enhancing quality control for acrylamide identification in processed potatoes.
  • PublicationOpen Access
    Análisis ergonómico de la viticultura moderna
    (Asociación Navarra de Ergonomía (ANER), 2023) González Moreno, Miguel Ángel; Ingeniería; Ingeniaritza; Institute of Smart Cities - ISC
    Se realiza la identificación de los principales riesgos ergonómicos en el sector vitícola a través del análisis de las diferentes labores realizadas durante una campaña completa, desde la poda invernal hasta la vendimia de la cosecha.
  • PublicationOpen Access
    Riesgos ergonómicos en las ITEAF
    (Asociación Navarra de Ergonomía (ANER), 2021) González Moreno, Miguel Ángel; Ingeniería; Ingeniaritza; Institute of Smart Cities - ISC
    Se realiza la identificación de los principales riesgos ergonómicos en las ITEAF, y en particular los asociados a los dos puestos de trabajo del “Inspector” y “Director técnico”, conforme se recoge en el Real Decreto 1702/2011, de 18 de noviembre, de inspecciones periódicas de los equipos de aplicación de productos fitosanitarios.
  • PublicationOpen Access
    Design and analysis of a two-stage cascade system for heating and hot water production in nearly zero-energy buildings using thermoelectric technology
    (MDPI, 2024-12-16) Ordóñez, Javier ; Díaz de Garayo, Sergio; Martínez Echeverri, Álvaro; Algarra Pérez, Fernando; Astrain Ulibarrena, David; Ingeniería; Ingeniaritza; Institute of Smart Cities - ISC; Gobierno de Navarra / Nafarroako Gobernua
    This paper proposes an innovative system that integrates two thermoelectric heat pumps (one air–water and the other water–water) with two thermal storage tanks at different temperatures to provide heating and domestic hot water to a 73.3 m2 passive-house-certified dwelling in Pamplona (Spain). The air–water thermoelectric heat pump extracts heat from the ambient air and provides heat to a tank at intermediate temperature, which supplies water to a radiant floor. The water–water heat pump takes heat from this tank and provides heat to the other tank, at higher temperature, which supplies domestic hot water. The system performance and comfort conditions are computationally analyzed during the month of January under the climate of Pamplona and under different European climates. The COP of the system lays between 1.3 and 1.7, depending on the climate, because of the low COP of the air–water thermoelectric heat pump. However, it is able to provide water for the radiant floor and to maintain the temperature of the dwelling above 20 °C 99.8% of the time. Moreover, it provides domestic hot water at a temperature above 43 °C 99.9% of the time. Noteworthy is the fact that the water–water heat pump presents a COP close to 4, which opens up the possibilities of working in combination with more efficient heat pumps for the first stage.
  • PublicationOpen Access
    Processing parameter setting procedure for a commercial bowden tube FDM printer
    (MDPI, 2024-10-22) Aguirre Fernández, Pablo Sebastián; Veiga Suárez, Fernando; Irijalba, Mikel ; Villabona Gorri, Eneko; Rivero Fuente, Pedro J.; Ingeniería; Ingeniaritza
    Additive manufacturing (AM), especially fused deposition modeling (FDM), has experienced great development and diffusion during recent years. However, it still faces some limitations, such as poor dimensional accuracy or surface defects, the improvement of which motivates the elaboration of the present work. Contrary to an approach based on the optimization of parameters to obtain a single invariant value, the main objective of this study is the design of a procedure that anyone can follow to generate a printing profile for their specific FDM printer, environment, and imposed constraints through the adjustment of some selected parameters in the popular slicing software UltiMaker Cura. The resulting procedure consists of four ad hoc designed specimens and their analysis algorithms, all connected by a general workflow that ensures the correct execution of the procedure. Its applicability and effectiveness have been proved in a case study where a printing profile was developed for the real manufacturing project of a custom 3D object in polylactic acid (PLA), obtaining an improvement of 50% in tolerances and proving that the proposed parameter setting procedure represents a reduction in the setting time and material consumption versus conventional trial and error methodologies.
  • PublicationOpen Access
    The characterization of the alcoholic fermentation process in wine production based on acoustic emission analysis
    (MDPI, 2024-12-07) Sánchez Roca, Ángel; Latorre Biel, Juan Ignacio; Jiménez Macías, Emilio; Sáenz Díez, Juan Carlos; Blanco Fernández, Julio; Ingeniería; Ingeniaritza; Institute of Smart Cities - ISC
    The present experimental study assessed the viability of utilizing an acoustic emission signal as a monitoring instrument to predict the chemical characteristics of wine throughout the alcoholic fermentation process. The purpose of this study is to acquire the acoustic emission signals generated by CO₂ bubbles to calculate the must density and monitor the kinetics of the alcoholic fermentation process. The kinetics of the process were evaluated in real time using a hydrophone immersed in the liquid within the fermentation tank. The measurements were conducted in multiple fermentation tanks at a winery engaged in the production of wines bearing the Rioja Denomination of Origin (D.O.) designation. Acoustic signals were acquired throughout the entirety of the fermentation process, via a sampling period of five minutes, and stored for subsequent processing. To validate the results, the measurements obtained manually in the laboratory by the winemaker were collected during this stage. Signal processing was conducted to extract descriptors from the acoustic signal and evaluate their correlation with the experimental data acquired during the process. The results of the analyses confirm that there is a high linear correlation between the density data obtained from the acoustic analysis and the density data obtained at the laboratory level, with determination coefficients exceeding 95%. The acoustic emission signal is a valuable decision-making tool for technicians and winemakers due to its sensitivity when describing variations in kinetics and density during the alcoholic fermentation process.
  • PublicationOpen Access
    Comparative study of electrospun polydimethylsiloxane fibers as a substitute for fluorine-based polymeric coatings for hydrophobic and icephobic applications
    (MDPI, 2024-11-30) Vicente Gómara, Adrián; Rivero Fuente, Pedro J.; Santos, Cleis; Rehfeld, Nadine; Rodríguez Trías, Rafael; Ingeniería; Ingeniaritza; Institute for Advanced Materials and Mathematics - INAMAT2; Universidad Pública de Navarra / Nafarroako Univertsitate Publikoa, PJUPNA1929
    The development of superhydrophobic, waterproof, and breathable membranes, as well as icephobic surfaces, has attracted growing interest. Fluorinated polymers like PTFE or PVDF are highly effective, and previous research by the authors has shown that combining these polymers with electrospinning-induced roughness enhances their hydro- and ice-phobicity. The infusion of these electrospun mats with lubricant oil further improves their icephobic properties, achieving a slippery liquid-infused porous surface (SLIPS). However, their environmental impact has motivated the search for fluorine-free alternatives. This study explores polydimethylsiloxane (PDMS) as an ideal candidate because of its intrinsic properties, such as low surface energy and high flexibility, even at very low temperatures. While some published results have considered this polymer for icephobic applications, in this work, the electrospinning technique has been used for the first time for the fabrication of 95% pure PDMS fibers to obtain hydrophobic porous coatings as well as breathable and waterproof membranes. Moreover, the properties of PDMS made it difficult to process, but these limitations were overcome by adding a very small amount of polyethylene oxide (PEO) followed by a heat treatment process that provides a mat of uniform fibers. The experimental results for the PDMS porous coating confirm a hydrophobic behavior with a water contact angle (WCA) ≈ 118° and roll-off angle (αroll-off) ≈ 55°. In addition, the permeability properties of the fibrous PDMS membrane show a high transmission rate (WVD) ≈ 51.58 g∙m−2∙d−1, providing breathability and waterproofing. Finally, an ice adhesion centrifuge test showed a low ice adhesion value of 46 kPa. These results highlight the potential of PDMS for effective icephobic and waterproof applications.
  • PublicationOpen Access
    Solving the solute transport equation using breakthrough curve modeling
    (MDPI, 2024-11-22) Panahi Sofla, Amir; Ghameshlou, Arezoo N.; Liaghat, Abdolmajid; Campo-Bescós, Miguel; Seyedzadeh, Amin; Ingeniería; Ingeniaritza; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD
    The movement of solutes in soil is crucial due to their potential to cause soil and groundwater pollution. In this study, a mathematical model based on the Advection Dispersion Equation (ADE) was developed to evaluate solutions for solute transport. This equation enabled us to attain a relationship for concentrations at different locations and times, also known as the breakthrough curve. Five columns (5 cm in diameter and 30 cm in height) of soil types were prepared to check the validity of the results. An evaluation of the calculated relations showed high accuracy in estimating the breakthrough curve and the saturated hydraulic conductivity of the soil.
  • PublicationOpen Access
    Application of symmetric neural networks for bead geometry determination in wire and arc additive manufacturing (WAAM)
    (MDPI, 2025-02-21) Fernández Zabalza, Aitor; Veiga Suárez, Fernando; Suárez, Alfredo; Uralde Jiménez, Virginia; Sandúa Fernández, Xabier; Alfaro López, José Ramón; Ingeniería; Ingeniaritza; Institute for Advanced Materials and Mathematics - INAMAT2
    The accurate prediction of weld bead geometry is crucial for ensuring the quality and consistency of wire and arc additive manufacturing (WAAM), a specific form of directed energy deposition (DED) that utilizes arc welding. Despite advancements in process control, predicting the shape and dimensions of weld beads remains challenging due to the complex interactions between process parameters and material behavior. This paper addresses this challenge by exploring the application of symmetrical neural networks to enhance the accuracy and reliability of geometric predictions in WAAM. By leveraging advanced machine learning techniques and incorporating the inherent symmetry of the welding process, the proposed models aim to precisely forecast weld bead geometry. The use of neuronal networks and experimental validation demonstrate the potential of symmetrical neural networks to improve prediction precision, contributing to more consistent and optimized WAAM outcomes.
  • PublicationOpen Access
    High deposition wire arc additive manufacturing of mild steel: strategies and heat input effect on microstructure and mechanical properties
    (Elsevier, 2020-09-02) Aldalur, Eider; Veiga Suárez, Fernando; Suárez, Alfredo; Bilbao, Jon; Lamikiz, Aitzol; Ingeniería; Ingeniaritza
    Wire Arc Additive Manufacturing (WAAM) is a layer-by-layer production concept that is proposed as a promising alternative to traditional subtractive techniques due to its potential to manufacture large metallic components of medium geometrical complexity. In recent years, this technology has created interest due to the advantages it proposes, such as a low cost and high deposition rates in comparison with other Additive Manufacturing (AM) techniques. In this study, the Gas Metal Arc Welding (GMAW)-based WAAM system was developed to deposit mild steel material. To that end, a comprehensive methodology to understand the main process variables and their influence in the final component properties is shown. The aim of the present study was to compare the influence of oscillatory and overlapping deposition strategies in terms of productivity, growth per layer, obtained microstructure and mechanical properties using the control volume concept to compare volume-dependent parameters. Although some characteristics of these strategies have been documented in literature, the heat input influence has not yet been comprehensively demonstrated and understood. For example, heat input, analyzed deeply in the present study, is a critical factor for the stability of the WAAM process, influencing the mechanical properties and microstructural evolution of as-fabricated parts. The results indicate that the oscillated strategy increases productivity.