THE FIVE COMPETITION WINNERS
05. Breakage, coalescence and size distribution of surfactant-laden droplets
Alessio Roccon, University of Udine, Italy
Giovanni Soligo, University of Udine, Italy
Alfredo Soldati, University of Udine, Italy
Abstract
In this work, we investigate the breakage, coalescence, and the resulting size distribution of a swarm of surfactant-laden droplets in turbulence. We consider two different values of the surface tension and four types of surfactant. We observe that, for all investigated cases, the steady-state droplet size distribution is in good agreement with the −10/3 power-law scaling, conforming to previous experimental observations and numerical simulations.
Energy
10. Immersed finite element analysis of laser powder bed fusion process: Modeling and experimental validation
Massimo Carraturo, University of Pavia, Italy
John Jomo, Technical University of Munich, Germany
Stefan Kollmannsberger, Technical University of Munich, Germany
Ernst Rank, Technical University of Munich, Germany
Alessandro Reali, University of Pavia, Italy
Ferdinando Auricchio, University of Pavia, Italy
Abstract
The capability of correctly predicting part deflections after support removal is important to assess the quality of a final artifact produced by laser powder bed fusion (LPBF) technology. Due to the high flexibility of LPBF additive manufacturing, most of the components produced by means of such a technology have an optimized shape and complex geometrical features. Consequently, the process of generating an analysis suitable mesh starting from the original 3D virtual model turns out to be a non-trivial task. Immersed boundary methods represent a possible solution to perform accurate process simulation without the meshing burden. In this work an in-house developed immersed finite element framework suitable to perform thermo-mechanical part-scale analysis is experimentally validated by means of part deflection measurements obtained for a single-cantilever structure after support removal.
Civil Engineering
17. Patient-specific multiscale modeling of in-stent restenosis: integrating hemodynamics, gene expression and cellular dynamics
Anna Corti, Politecnico di Milano, Italy
Monika Colombo, Politecnico di Milano, Italy
S. Casarin, Houston Methodist Hospital, USA
J. Rozowsky, University of Florida, USA
Y. He, University of Florida, USA
F. Migliavacca, Politecnico di Milano, Italy
J. F. Rodriguez Matas, Politecnico di Milano, Italy
S. Berceli, University of Florida, USA; Malcom Randall VAMC, USA
C. Chiastra, Politecnico di Milano, Italy; Politecnico di Torino, Turin, Italy
Abstract
The activation of an inflammatory response and the disturbed hemodynamics were identified to play a role in the so-called in-stent restenosis (ISR), one of the main drawbacks of stenting in femoral arteries. In silico models can provide further insight into the underlying mechanobiological processes of ISR. Here, we present a multiscale framework replicating the process of ISR at cell/tissue scales by integrating computational fluid dynamics (CFD) and monocyte gene expression, accounting for systemic inflammation, with an agent-based model (ABM) of cellular dynamics.
Biomechanics
18. Integrating theory and population data to forecast the spatiotemporal spread of COVID-19
Alex Viguerie, University of Pavia, Italy
Guillermo Lorenzo, The University of Texas at Austin, USA
Ferdinando Auricchio, University of Pavia, Italy
Davide Baroli, RWTH Aachen
Thomas J.R. Hughes, The University of Texas at Austin, USA
Alessia Patton, The University of Pavia, Italy
Alessandro Reali, The University of Pavia, Italy
Thomas E. Yankeelov, The University of Texas at Austin, USA
Alessandro Veneziani, Emory University
Abstract
We propose a partial differential equation (PDE) model constrained with available demographic, geographic, and epidemiologic data to describe the spatiotemporal contagion of COVID-19. The model follows the SEIRD (susceptible-exposed-infected-recovered-deceased) framework, and features a diffusion term with heterogeneous coefficient to describe the spread of living-person model compartments. The model is validated against real-world data in the Italian region of Lombardy, and shows good predictive ability. Such an approach may be a powerful tool in the planning of public health interventions.
Biomechanics
22. Life safety assessment in multi-storey building fires
Ada Malagnino, University of Salento, Italy
Angelo Corallo, University of Salento, Italy
Giorgio Zavarise, Politecnico di Torino, Italy
Simo Hostikka, Aalto University, Finland
Abstract
Life safety is one of the most important objectives of Performance Based Fire-Design and is commonly considered achieved if building occupants escape the fire effects unharmed. The research main scope is to assess life safety in a multi-storey building fire, a hotel located in Lecce, Italy. Statistics based fire risk assessment is used to choose the fire scenario to be simulated considering damage severity and likelihood of occurrence. In the fire simulations, particular attention is given to toxicity of combustion products. Fire simulations results are integrated with evacuation simulations.
Civil Engineering
THE FINALISTS
01. TASR: The Transient Air System Rig for Turbocharger Model Validation
Aaron Costall, Imperial College London, United Kingdom
Wei Sheng Cheong, Imperial College London, United Kingdom
Harminder Flora, Imperial College London, United Kingdom
Asanka Munasinghe, Imperial College London, United Kingdom
Abstract
Transport emissions contribute to climate change and air quality global challenges. Electrifying vehicles will take decades, so combustion engine efficiency must be improved. Turbocharging improves efficiency and reduces emissions. These complex systems are designed by simulation, but model inaccuracies force many iterations. Accurate models are key but require validation. TASR recreates transient-pulsating flow for realistic validation data without an engine. 1D simulations show how it creates pulses of desired shape, frequency and amplitude, producing valuable data to improve model accuracy.
Automotive
02. Production Planning: A Practical Approach for the Use of Simulation-Based Optimization
Michael Kranz, Institute of Industrial Engineering and Ergonomics, RWTH Aachen University, Germany
Maximilian Duisberg, Institute of Industrial Engineering and Ergonomics, RWTH Aachen University, Germany
Benedikt a. Latos, Institute of Industrial Engineering and Ergonomics, RWTH Aachen University, Germany
Jan Brinkjans, Miele & Cie. KG, Gütersloh, Germany
Sebastian Tschöpe, Miele & Cie. KG, Gütersloh, Germany
Susanne Mütze-Niewöhner, Institute of Industrial Engineering and Ergonomics, RWTH Aachen University, Germany
Abstract
Machine scheduling is one of the most important tasks in in-house production planning and control and belongs to the group of NP-heavy combinatorial optimisation problems. This poster uses a practical case study to demonstrate the extent to which simulation-based optimisation, which enables a dynamic approach to the system, can support employees in detailed production planning.The results of the simulation show, among other things, that in this case study the machine occupancy time could have been reduced by about 14.2% compared to reality in the period under consideration.
Consumer Goods
03. Sailboat keel optimization
Marco Maganzi, University of Pisa, Italy
Giovanni Lombardi, University of Pisa, Italy
Abstract
The Sport at high level is a powerful engine for the Research, in particular for Aerodynamics.
The purpose of this work is optimization of the keel in order to reduce the drag of a sailboat during the race.
Marine
04. EUCLID - Payload Module and Service Module Structural Analysis
Stefano Guidolotti, University of Pisa - Aerospace Engineering, Italy
Marco Brizzi, University of Pisa - Aerospace Engineering, Italy
Lorenzo Frassini, University of Pisa - Aerospace Engineering, Italy
Abstract
Euclid is an ESA mission to map the geometry of the Universe and better understand the mysterious dark matter and dark energy, which make up most of the energy budget of the cosmos. The aim of this project is to better understand the behaviour of Euclid’s main structure under the applied mission loads. Starting from the high fidelity re-construction of the spacecraft model using SOLIDWORKS 2019, accurate responses of the Payload and Service module were evaluated through the mechanical environment induced by the launch vehicle (Soyuz ST-B). A huge preliminary study regarding the interfaces between components, materials’ selection and design modelling has been performed. The structural analysis have been carried out using ANSYS 19.2. From the detailed model it has been obtained a simplified structure used as input for the simulations. Results in terms of modal analysis show a fundamental frequency in longitudinal and lateral direction of 38.7 Hz and 16.5 Hz respectively: these are excellent compared with related papers and also satisfy the user’s guide constraints. Various analysis (QSL, random vibration, SRS) have been performed and for each study-case, the results were obtained in terms of total deformation and equivalent Von-Mises stresses. The simulations give a good overview of which are the most stressed areas and the most loaded joints, that have been verified in detail in the last section. All the evaluated deformations, are compatible with the optical alignment of the telescope and also with the integrity of the S/C inside the fairing.
Aerospace
05. Breakage, coalescence and size distribution of surfactant-laden droplets
Alessio Roccon, University of Udine, Italy
Giovanni Soligo, University of Udine, Italy
Alfredo Soldati, University of Udine, Italy
Abstract
In this work, we investigate the breakage, coalescence, and the resulting size distribution of a swarm of surfactant-laden droplets in turbulence. We consider two different values of the surface tension and four types of surfactant. We observe that, for all investigated cases, the steady-state droplet size distribution is in good agreement with the −10/3 power-law scaling, conforming to previous experimental observations and numerical simulations.
Energy
06. How Different Lower Limb Movements Impact on the Hemodynamics of the Femoropopliteal Artery: A Computational Study
Ludovica Cestariolo, Politecnico di Milano, Italy
Giulia Luraghi, Politecnico di Milano, Italy
Monika Colombo, Politecnico di Milano, Italy
Maddalena Ravasi, Politecnico di Milano, Italy
Anna Airoldi, Politecnico di Milano, Italy
Claudio Chiastra, Politecnico di Torino e Politecnico di Milano, Italy
Giancarlo Pennati, Politecnico di Milano, Italy
Abstract
Femoropopliteal Artery (FPA) is exposed to a wide range of deformations and it is often affected by atherosclerotic plaque development. Albeit hemodynamics seems to be an important factor in driving plaque development, no study considers the dynamicity of a realistic movement.
A one-way coupling FSI analysis was employed to perform the simulations. Three different movements have been analyzed and the hemodynamics was compared between moving- and fixed-boundary models. The results were analyzed in terms of velocity field and hemodynamic indexes (i.e. TAWSS, OSI, and RRT).
Biomechanics
07. Gamifying the MRI Experience
Thomas Boutelle, Imperial College London / King's College London, Great Britain
Gabriella Segal, Imperial College London, Great Britain
Constance de Cler, Imperial College London, Great Britain
Caitlin Edgar, Imperial College London, Great Britain
Simon Oury, Imperial College London, Great Britain
Ella Reich, Imperial College London, Great Britain
Meha Vora, Imperial College London, Great Britain
Warren Macdonald, Imperial College London, Great Britain
Abstract
We have designed and developed a Movement Detection System (MDS) using a segmented Movement Detection Board (MDB) and a Force Sensitive Resistor (FSR) array, which integrates and feeds into one of two motion reactive, eye-gaze controlled video games we have designed to operate during an MRI scan. Successful component testing has culminated in complete MDS testing, which shows an accurate responsive system capable of relaying patient movements to our gaming system. We detail a proposed clinical trial to prove our system’s effectiveness in reducing motion and anxiety in paediatric patients.
Biomechanics
08. 3D-printed ankle-foot orthosis: a design method
Alberto Dal Maso, University of Trieste, Italy
Francesca Cosmi, University of Trieste, Italy
Alberto Dal Maso, University of Trieste, Italy
Francesca Cosmi, University of Trieste, Italy
Abstract
Additive manufacturing offers several advantages when compared to conventional manufacturing technologies, especially where large scale customization is requested. In this article, a procedure for the design of a fully-customized 3D-printed ankle-foot orthosis (AFO) is described, with reference to a case study regarding a 21-year-old woman with an injured ankle. The first step is the acquisition of the geometrical data from the patient’s foot: this is done using photogrammetry. The second step is the data conversion and import in a CAD modeler; SolidWorks™ is chosen for this purpose. The AFO is modelled parametrically around the foot mesh and optimized in order to resist the predicted mechanical stresses. Finally, the device is 3D-printed on an FDM printer and tested on the patient. An excellent geometrical correspondence between the AFO and the patient’s foot is highlighted: this leads to great comfort and enhances medical functionality. The described procedure can be easily automated, further reducing the lead time and costs of the whole process.
Biomechanics
09. On the development of an imaging system at millimetre-wave frequencies for early breast cancer detection
Simona Di Meo, University of Pavia, Italy
Abstract
In recent years, it is growing the interest toward the utilization of electromagnetic waves for biomedical applications. One of the most promising application is the use of microwaves and millimetre waves for diagnostic purpose, in particular for breast cancer detection. In this poster, a complete overview of the work done at the University of Pavia about the development of an innovative mm-wave imaging system for early-stage breast cancer detection in fatty tissues is given.
Appliances
10. Immersed finite element analysis of laser powder bed fusion process: Modeling and experimental validation
Massimo Carraturo, University of Pavia, Italy
John Jomo, Technical University of Munich, Germany
Stefan Kollmannsberger, Technical University of Munich, Germany
Ernst Rank, Technical University of Munich, Germany
Alessandro Reali, University of Pavia, Italy
Ferdinando Auricchio, University of Pavia, Italy
Abstract
The capability of correctly predicting part deflections after support removal is important to assess the quality of a final artifact produced by laser powder bed fusion (LPBF) technology. Due to the high flexibility of LPBF additive manufacturing, most of the components produced by means of such a technology have an optimized shape and complex geometrical features. Consequently, the process of generating an analysis suitable mesh starting from the original 3D virtual model turns out to be a non-trivial task. Immersed boundary methods represent a possible solution to perform accurate process simulation without the meshing burden. In this work an in-house developed immersed finite element framework suitable to perform thermo-mechanical part-scale analysis is experimentally validated by means of part deflection measurements obtained for a single-cantilever structure after support removal.
Civil Engineering
11. Powertrain mounts dynamc characterization for low frequency structure borne noise prediction
Andrea Ricci, BMW AG, Germany; University of Trieste, Italy
Luigi Bregant, University of Trieste, Italy
Frank Albertz, BMW AG, Germany
Abstract
The acoustic performance, in the development of luxury class vehicles, is very important. In the latter development stages, it becomes essential to predict the influence and effects of sub- components’ modification in the global car. Due to the complexity of creating models for the entire vehicle, the dynamic substructures, and in particular the component-based dynamic substructures, are used for this purpose. The booming noise, linked to the engine firing order, is a phenomenon that occurs rather often in vehicles with internal combustion engine, but also in the family of hybrid vehicles that still have such type of engines. As shown in the figure, for frequencies between 20-80 Hz the noise in the cabin is largely dominated by the boom resulting from the engine combustion. In the advanced stages of development, the modification of the mounts characteristics represents one of the most feasible way to reduce booming noise issues. Other modifications would have a much larger and difficult to control impact.
Automotive
12. CAE-based design of a cable driven human-like robotic wrist
Mario Baggetta, University of Genoa, Italy
Pietro Bilancia, University of Genoa, Italy
Giovanni Berselli, University of Genoa, Italy
Luca Bruzzone, University of Genoa, Italy
Pietro Fanghella, University of Genoa, Italy
Abstract
This work reports the design of a human-like robotic wrist, whose mobility has been realized by employing flexible components (FCs). To mimick the natural asymmetry of the human wrist, both in terms of angular deflection and passive stiffness, two contacts are included: the first ensures impact resistance, whereas the second increases the stiffness of the FC by acting on one of its beams. The design procedures and tools specifically developed for the wrist optimization are described. Direct comparisons between simulations and experiments confirm the efficacy of the proposed design method.
Mechanics
13. Lower leg biomechanics and ski boot: computational approach
Chiara Giulia Fontanella, University of Padova, Italy
Ilaria Toniolo, University of Padova, Italy
Lorenzo Bortolan, University of Verona, Italy
Emanuele Luigi Carniel, University of Padova, Italy
Abstract
Computer methods provide reliable support for the investigation of the mechanical functionality of biological structures. Computational models can be further exploited to analyze interaction phenomena between biological tissues and devices, providing data that allow for their reliability assessment and optimal design. With specific regard to ski boots, the methods of computational biomechanics allow analyzing the stress and the strain fields that occur within lower leg and foot tissues, depending on ski boot conformation, buckling level and skiing actions. Such mechanical stimuli determine relevant phenomena, with particular regard to vasoconstriction effects.
Biomechanics
14. Towards a validated human stomach computational model
Ilaria Toniolo, University of Padova, Italy
Chiara Giulia Fontanella, University of Padova, Italy
Mirto Foletto, IFSO Bariatric Centre of Excellence, Policlinico Universitario
Emanuele Luigi Carniel, University of Padova, Italy
Abstract
The aim of the research activities consists in the characterization of human gastric tissues mechanics, which is necessary to develop a reliable computational model of the human stomach. The methods of biomechanics can rationally deal with the main limits and drawbacks of bariatric surgery (the surgery that treats people affected by obesity) improving its effectiveness. In future, computational gastric models could be very useful to customize the surgical procedure on patient‘s medical condition, avoiding experimentation on animal model and/or preliminary clinical trials.
Biomechanics
15. Evolution of melt pool and porosity during laser powder bed fusion of Ti6Al4V alloy: numerical modelling and experimental validation
Chiara Ransenigo, University of Brescia, Italy
Marialaura Tocci, University of Brescia, Italy
Abstract
Laser powder bed fusion (L-PBF) is one of the most promising additive manufacturing technologies for metals, in which a laser selectively melts a pre-deposited bed of microscopic metal powders. Nowadays, final build quality is still limited because of the presence of defects like porosities that are very hard to be avoided. In this context, numerical simulation has imposed as a powerful tool for defects prediction and process optimization but still its reliability has to be fully demonstrated. In this work, a commercial CFD software, FLOW-3D AM, was used for Ti alloys AM to understand the formation of porosity and experimental tests were performed to validate the model.
Aerospace
16. Comparison between detailed (CFD) and simplified models for the prediction of solid particle size distribution in fluidized bed reactors
Carmine Sabia, SUPSI, Switzerland - Politecnico di Torino, Italy
Marco Ferasin, Politecnico di Milano, Italy
Tommaso Casalini, ETH Zürich, Switzerland
Antonio Buffo, Politecnico di Torino, Italy
Daniele L. Marchisio, Politecnico di Torino, Italy
Maurizio C. Barbato, SUPSI, Switzerland
Giuseppe Storti, ETH Zürich, Switzerland
Abstract
This work is aimed at developing a simplified model suitable to effectively describe the fluidization behavior within fluidized beds with minimal computational efforts. The simplified model was validated through detailed CFD Euler-Euler simulations showing a good agreement in the case of large particles (about 450 micron) at all the gas velocities considered (20, 40, 61 cm/s). Slightly less accurate outcomes were observed for smaller particles (about 220 micron). This was due to the underestimation of the particle size effect on the fluidization behavior by the simplified approach.
Mechanics
17. Patient-specific multiscale modeling of in-stent restenosis: integrating hemodynamics, gene expression and cellular dynamics
Anna Corti, Politecnico di Milano, Italy
Monika Colombo, Politecnico di Milano, Italy
S. Casarin, Houston Methodist Hospital, USA
J. Rozowsky, University of Florida, USA
Y. He, University of Florida, USA
F. Migliavacca, Politecnico di Milano, Italy
J. F. Rodriguez Matas, Politecnico di Milano, Italy
S. Berceli, University of Florida, USA; Malcom Randall VAMC, USA
C. Chiastra, Politecnico di Milano, Italy; Politecnico di Torino, Turin, Italy
Abstract
The activation of an inflammatory response and the disturbed hemodynamics were identified to play a role in the so-called in-stent restenosis (ISR), one of the main drawbacks of stenting in femoral arteries. In silico models can provide further insight into the underlying mechanobiological processes of ISR. Here, we present a multiscale framework replicating the process of ISR at cell/tissue scales by integrating computational fluid dynamics (CFD) and monocyte gene expression, accounting for systemic inflammation, with an agent-based model (ABM) of cellular dynamics.
Biomechanics
18. Integrating theory and population data to forecast the spatiotemporal spread of COVID-19
Alex Viguerie, University of Pavia, Italy
Guillermo Lorenzo, The University of Texas at Austin, USA
Ferdinando Auricchio, University of Pavia, Italy
Davide Baroli, RWTH Aachen
Thomas J.R. Hughes, The University of Texas at Austin, USA
Alessia Patton, The University of Pavia, Italy
Alessandro Reali, The University of Pavia, Italy
Thomas E. Yankeelov, The University of Texas at Austin, USA
Alessandro Veneziani, Emory University
Abstract
We propose a partial differential equation (PDE) model constrained with available demographic, geographic, and epidemiologic data to describe the spatiotemporal contagion of COVID-19. The model follows the SEIRD (susceptible-exposed-infected-recovered-deceased) framework, and features a diffusion term with heterogeneous coefficient to describe the spread of living-person model compartments. The model is validated against real-world data in the Italian region of Lombardy, and shows good predictive ability. Such an approach may be a powerful tool in the planning of public health interventions.
Biomechanics
19. FEM analysis of functional cavities to improve the thermo-mechanical properties of hollow bricks made up of 3D printable cement mortar
Matteo Sambucci, Department of Chemical and Materials Engineering, Sapienza University of Rome, Italy
Marco Valente, Department of Chemical and Materials Engineering, Sapienza University of Rome, Italy
Abstract
In this work, innovative inner architectures based on hexagonal and fractal cavities are proposed to design 3D printable cement mortar-based functional hollow bricks. FEM mechanical and thermal analysis were performed to evaluate the effect of optimized configurations on the bricks's properties. Hexagonal holes reduce the stress concentration in the material compared to conventional geometries, improving the component's strain capacity and strength. High geometric complexity of fractal cavities maximizes the thermal path of heat flow, resulting in greater thermal attenuation than the other architectures.
Civil Engineering
20. Non-intrusive data-driven structural optimization with ROMs and parameter space reduction
Marco Tezzele, SISSA, Scuola Internazionale Superiore di Studi Avanzati, Mathematics Area, mathLab, Trieste, Italy
Gianluigi Rozza, SISSA, Scuola Internazionale Superiore di Studi Avanzati, Mathematics Area, mathLab, Trieste, Italy
Abstract
We present a structural optimization computational pipeline. We exploit MSC Patran and MSC Nastran softwares to create a solutions database for differ- ent input parameters. Then we apply non-intrusive Reduced Order Methods (ROMs) such as Proper Orthogonal Decomposition with Interpolation (PODI) to predict the solution fields of interest, and Active Subspaces (AS) to reduce the parameter space dimensionality and perform sensitivity analysis over the parameters, using open source Python packages.
Finally Bayesian optimization is employed to minimize a target scalar function while ROMs serve as enablers for fast and accurate real-time evaluations.
Civil Engineering
21. Computer-assisted design defines a novel actuation principle based on liquid structures
Paolo Gallina, University of Trieste, Italy
Massimiliano Gei, University of Trieste, Italy
Lorenzo Scalera, University of Udine, Italy
Stefano Seriani, University of Trieste, Italy
Abstract
We present a framework for new structural metamaterials we refer to as liquid structures: a topology of bistable mechanisms made up of a high number of cells that are sub-mechanisms composed of pseudo-rigid links and joints. The name liquid structures comes from the similarities they present with the kinematics of the constant flow of incompressible fluids they are inspired to in a limited domain. Computational Fluid Dynamics (CFD) is employed to define the layout of the cells through a two-step process where: (i) the node displacements are computed by the CFD tool itself; (ii) the kinematic synthesis of each cell is subsequently performed. We report an illustrative case and an example of application (a brake system) where star- and diamond-type cells are employed. Our proposal opens a new avenue of computer-assisted design of mechanical actuators.
Mechanics
22. Life safety assessment in multi-storey building fires
Ada Malagnino, University of Salento, Italy
Angelo Corallo, University of Salento, Italy
Giorgio Zavarise, Politecnico di Torino, Italy
Simo Hostikka, Aalto University, Finland
Abstract
Life safety is one of the most important objectives of Performance Based Fire-Design and is commonly considered achieved if building occupants escape the fire effects unharmed. The research main scope is to assess life safety in a multi-storey building fire, a hotel located in Lecce, Italy. Statistics based fire risk assessment is used to choose the fire scenario to be simulated considering damage severity and likelihood of occurrence. In the fire simulations, particular attention is given to toxicity of combustion products. Fire simulations results are integrated with evacuation simulations.
Civil Engineering
23. Impact of rotor tower and blockage effects in a hybrid BEM-CFD simulation of a vertical-axis hydrokinetic turbine
Caterina Giovannini, University of Pisa, Italy
Diana Cremoncini, University of Pisa, Italy
Stefania Zanforlin, University of Pisa, Department of Energy, Systems, Territory and Constructions Engineering (DESTEC), Italy
Abstract
An analysis of performance and wake characteristics of a vertical-axis turbine was carried out
inside a water channel, simulated by a hybrid BEM-CFD based on Ansys-ICEM and
Ansys-FLUENT. The turbine was simulated at different tip immersion depths, with and without its rotor tower, in a narrow channel and in an unconfined environment and the results were compared. Since this numerical study was conceived to help planning a real experimental campaign, turbine and channel dimensions and operating conditions are similar to those of IFREMER laboratory in Boulogne-sur-mer.
Energy
24. Finite element residual stresses analysis and fatigue assessment of a pipe-to-plate welded joint
Andrea Chiocca, University of Pisa, Department of Civil and Industrial Engineering, Italy
Francesco Frendo, University of Pisa, Italy
Leonardo Bertini, University of Pisa, Italy
Abstract
Residual stresses are an inseparable consequence of the most common manufacturing processes, resulting in high magnitude and not easily predictable stress field inside the material. Fatigue design codes usually account residual stresses through highly conservative assumptions, resulting in poorly optimized designs or unexpected failures. To this regard, the following work investigates the influence of residual stresses in the fatigue assessment of a pipe-to-plate welded joint made of S355JR structural steel. An uncoupled thermo-structural finite element simulation was performed to evaluate the overall residual stress field in the specimen due to the welding process. The thermal problem was first solved and then the results, in terms of nodal temperatures, were used in the structural analysis as thermal loads. Secondly, the resulting residual stresses were embedded in a finite element model as an initial condition before fatigue loading application.
Mechanics
25. Deep learning as a surrogate of finite element analysis to estimate intraoperative deformations during EVAR procedures
Alice Fantazzini, Department of Experimental Medicine, University of Genoa; Camelot Biomedical Systems S.r.l., Italy
Michele Conti, Department of Civil Engineering and Architecture, University of Pavia, Italy
Curzio Basso, Camelot Biomedical Systems S.r.l., Italy
Giovanni Spinella, Vascular and Endovascular Surgery Unit, IRCCS Ospedale Policlinico San Martino, University of Genoa, Genoa, Italy
Abstract
Finite element analysis (FEA) estimates the aortic deformations during endovascular aneurysm repair. Since FEA is time consuming, a deep learning (DL) model is proposed as FEA surrogate to predict these deformations. FEA is performed on shapes generated with a statistical shape model, and a DL model is used to map the preoperative to the intraoperative shapes. The training set results highlight the potential of using a DL model as FEA surrogate. Such surrogate model will enable faster predictions, making it suitable for clinical workflows.
Biomechanics
26. A hollowing Topology Optimization method for additive and traditional manufacturing technologies
Fabio Salmeri, University of Messina, Italy
Marcello Raffaele, University of Messina, Italy
Filippo Cucinotta, University of Messina, Italy
Abstract
Thanks to the greater availability and technological evolution of rapid prototyping, attention has recently grown on the ability to design topologically optimized components in order to reduce their weight but at the same time maintain good mechanical resistance characteristics.
In this work, a topological optimization method is proposed starting from a grid of prefixed points in space to which the information obtained from a finite element analysis is associated. Topological optimization is performed by the Rhino’s plugin Grasshopper, and consists of a parametric environment in the form of graphical algorithms.
The points on the grid represent the seeds from which the hollowing of the component will start.
The proposed method uses a monoparametric algorithm that varies the diameter of the holes that hollow the component as an inverse function of the intensity of the stresses acting. Through FE analysis conducted within Ansys Workbench, the distribution and intensity of the stresses on the specimen are obtained, which once insert on the algorithm are used to parametrize the diameter of the holes.
The potential of the method is represented by the ability of the algorithm to modify the CAD directly, guaranteeing topologies ready to be made, without further post processing by the designers. Thanks to the simplicity of the hollowing pattern, the result is it suitable to be made with both additive manufacturing and traditional subtractive technologies.
In a case study, once the model has been obtained, a beam sample has been printed by means of FDM 3D printing technique and tested with a 3-point bending test. A comparison of the original and the optimized beam has been carried out, monitoring the printing time, with about a 50% increase, and the strength/weight ratio, with about a 20% increase.
Mechanics
27. Localized linearization technique for FSI analysis of patient-specific aortic aneurysm
Emanuele Vignali, Fondazione Toscana Gabriele Monasterio, Italy
Stephane Avril, Mines Saint-Etienne, Université de Lyon, France
Simona Celi, Fondazione Toscana Gabriele Monasterio, Italy
Abstract
The Fluid-Structure Interaction (FSI) emerges as a reliable tool for ascending thoracic aortic aneurysm (aTAA) analysis. A linearization method preserving the local material stiffness is needed. To this purpose, the Small on Large (SOL) approach is proposed. The simulation is split in a large deformation step going from the zero-pressure configuration to the diastole and a small deformation step going from the diastole to the systole. This work presents a computational framework for the implementation of SOL linearization approach for a patient-specific aTAA model in the Ansys environment.
Biomechanics
28. Design of High Performance Flexural Joints for Additive Manufacturing
Flaviana Calignano, Politecnico di Torino, Italy
Manuela Galati, Politecnico di Torino, Italy
Abstract
Assembling, friction and lubrifaction are the main issues when designing traditional rigid mechanisms. Flexure-based compliant mechanisms overcome this problem because they are monolithic and gain their mobility thanks to a proper design and a material deflection. However, the accurate and convenient design and the production of such mechanisms remain critical. Thanks to its capabilities, Additive Manufacturing approach could attack this challenge and opens a new unexploited field.
Biomechanics
29. CFD Simulation of a passage of a Pirelli F1 wet tire on a puddle using Particleworks
Nicholas Agazzi, Polytechnic of Milan, Italy
Michele Merelli, EnginSoft, Italy
Abstract
CFD Simulation of a passage of a Pirelli F1 wet tire on a puddle using Particleworks, in order to provide tyre-water puddle simulation, evaluation of tyre footprint, splashing and water evacuation through treads.
Automotive
30. A novel seismic coat for superbonus 110% tax detraction on existing masonry buildings
Antonio Formisano, University of Naples Federico II, Italy
Generoso Vaiano, University of Naples Federico II, Italy
Antonio Roffo, University of Naples Federico II, Italy
Abstract
An innovative low-cost sustainable and reversible seismic coat as energetic and seismic upgrading system of existing masonry buildings is proposed. Firstly, the increase of energy and seismic performances of the proposed envelope system, which is applied outside the building to avoid its use interruption, is demonstrated through a FEM simulation of an experimental test using ABAQUS software. Then, the system is applied to a case study masonry building using SAP2000 software. Finally, the analysis results show the large energy and seismic benefits provided by the proposed seismic coat.
Civil Engineering
31. In-silico model of Left Atrial Appendage Occlusion: comparison with implantation in 3d printed patient specific geometry
Elisabetta Stretti, Politecnico di Milano, Italy
Maria Francesca Zaccone, Politecnico di Milano, Italy
A. Zaccaria, Politecnico di Milano, Italy
F. Danielli, Politecnico di Milano, Italy
E. Gasparotti, Università di Pisa, Fondazione Toscana Gabriele Monasterio, Italy
B.M. Fanni, Università di Pisa, Fondazione Toscana Gabriele Monasterio, Italy
K. Capellini, Università di Pisa, Fondazione Toscana Gabriele Monasterio, Italy
S. Celi, Università di Pisa, Italy
G. Pennati, Politecnico di Milano, Italy
L. Petrini, Politecnico di Milano, Italy
Abstract
Left Atrial Appendage Occlusion (LAAO) is a minimally invasive treatment option for patients affected by non-valvular atrial fibrillation. The aim of this work is to build and validate a finite element model of the Watchman implantation. Deployment tests in 3D-printed patient-specific geometries were performed to assess the reliability of the model. The analogy between in-vitro and in-silico models underlined the potential model’s ability to evaluate different implantation procedures in the pre-operative phase, making the model an additional instrument for the clinician for the LAAO success.
Biomechanics
32. CFD-3D Analysis of wave's effect on a submerged float
Paola Lupi, University of Pisa, Italy
Giada Tosi, University of Pisa, Italy
Abstract
For extracting energy from the sea flow one of the best devices is the horizontal axis tidal turbine (HATT). In the best sites wind-generated waves are strong and can penetrate deep by introducing oscillatory effects on the local flow. For this reason it’s necessary to install the turbine at a depth where the influence of the waves is not too strong. For high depths the turbine can be anchored at the sea bottom using a rope, and it's kept in place using a float. In this study, using the commercial code CFD Ansys Fluent and Ansys ICEM, is evaluated the best form of a submerged support float for a marine turbine. Afterwards, the effect produced by the surface waves on the best shape of the float previously identified is analysed.
Energy
33. A fast direct coupling between LS-DYNA and RBF mesh Morphing to test different car bonnet designs in simulated Frontal Impact crashes
Leonardo Geronzi, RBF Morph, Italy
Stefano Porziani, University of Rome Tor Vergata, Italy
Abstract
In the automotive field, design methods can be combined with structural studies in order to obtain a vehicle or a component with optimal performances and preserving safety requirements. Simulated Crash tests have become an indispensable tool for reducing costs and accelerating car development. The running of this kind of simulation is often entrusted to explicit solvers. This work wants to show the possibility to couple LS-DYNA explicit solver, one of the most used in automotive design, and RBF mesh morphing in order to test different shapes and models in simulations like Crash tests.
Automotive
34. Optimizing efficiency of flexible tandem wings using non-linear modes
Antonio Martínez-Pascual, University of Rome Tor Vergata, Rome, Italy
Corrado Groth, University of Rome Tor Vergata, Rome, Italy
Joaquín Ortega-Casanova, University of Malaga, Spain
Abstract
The aerodynamic performance of flexible flapping tandem wings in forward flight is evaluated using a novel non-linear modal superposition approach to carry the transient FSI analysis. It involves complex phenomena and the performance is very susceptible to changes in aerodynamic parameters. An optimization targeting maximum efficiency is performed on three aeroelastic parameters: flexibility, flapping frequency and amplitude
Biomechanics
35. A virtual decision engineering technology for jet engine design systems
Mohammad Hassannezhad, University of Sheffield, United Kingdom
Fatemeh Barzegar, Politecnico di Torino, Italy
Abstract
Making informed decisions in the lengthy and labour-intensive design projects, such as jet engine design, requires a proactive approach to quantify dynamics of changes and their ‘knock-on’ effects on downstream design workflows. This is particularly crucial in earlier stages where the information is imprecise, and frequent changeovers in product functions make it difficult to gather experience on operations. We introduce a user-friendly prototype tool, refers to the Virtual Propagation Nets (VPN), driven by a simple computational algorithm and deploy it in a real-world engineering case of aircraft engines.
Aerospace
36. SLICE Solar Lightweight Intelligent Component for Envelopes
Angelo Monteleone, Department of Civil Engineering and Architecture, University of Catania, Italy
Vincenzo Sapienza, Department of Civil Engineering and Architecture, University of Catania, Italy
Gianluca Rodonò, Department of Civil Engineering and Architecture, University of Catania, Italy
Abstract
One of the main goal of researches in architecture is to make new classes of advanced components, able to provide different performances to the changing needs of the users, continuously adapting themselves to the boundary conditions. SLICE is a component for lightweight adaptive envelopes, made with a composite material, which is capable to produce and store energy for its handling system, thanks to a high efficiency photovoltaic system integrated. The study also concerns the movement system, focusing on the application of folding surfaces, widely used in architecture.
Energy
Poster Award Sponsors
