Davide D'Angella M.Sc. Research Assistant Room: 3157 Email: Diese E-Mail-Adresse ist vor Spambots geschützt! Zur Anzeige muss JavaScript eingeschaltet sein! Tel: +49 89 289-23204 Fax: +49 89 289-25051

Research

• Simulation in applied mechanics
• Isogeometric Analysis
• High-order Finite Elements
• Adaptive discretization methods



Submittet Preprints

Journal Papers

• Jomo, J.; de Prenter, F.; Elhaddad, M.; D'Angella, D.; Verhoosel, C.; Kollmannsberger, S.; Kirschke, J.; Nübel, V.; van Brummelen, H.; Rank, E. Robust and parallel scalable iterative solutions for large-scale finite cell analyses
  Finite Elements in Analysis and Design - Status: Accepted for publication, 2019
  DOI: 10.1016/j.finel.2019.01.009
  
  
  
  
  
  
  
• Kollmannsberger, Stefan; D'Angella, Davide; Rank, Ernst; Garhuom, Wadhah; Hubrich, Simeon; Düster, Alexander; Stolfo, Paolo Di; Schröder, Andreas Show abstract Spline- and hp-basis functions of higher differentiability in the finite cell method
  GAMM-Mitteilungen 0 (0), pp. e202000004, 2019
  DOI: 10.1002/gamm.202000004 - Status: Verlagsversion / published
  
  
  
  In this paper, the use of hp-basis functions with higher differentiability properties is discussed in the context of the finite cell method and numerical simulations on complex geometries. For this purpose, Ck hp-basis functions based on classical B-splines and a new approach for the construction of C1 hp-basis functions with minimal local support are introduced. Both approaches allow for hanging nodes, whereas the new C1 approach also includes varying polynomial degrees. The properties of the hp-basis functions are studied in several numerical experiments, in which a linear elastic problem with some singularities is discretized with adaptive refinements. Furthermore, the application of the Ck hp-basis functions based on B-splines is investigated in the context of nonlinear material models, namely hyperelasticity and elastoplasicity with finite strains.
  
  
  
• D'Angella, D.; Kollmannsberger, S.; Rank, E.; Reali, A. Multi-level Bézier extraction for hierarchical local refinement of Isogeometric Analysis
  Computer Methods in Applied Mechanics and Engineering, 2018 - Status: Verlagsversion / published
  
  
  
  
  
  
  
• Onur Bas; Davide D'Angella; Jeremy G. Baldwin; Nathan J. Castro; Felix M. Wunner; Navid T. Saidy; Stefan Kollmannsberger; Alessandro Reali; Ernst Rank; Elena M. De-Juan-Pardo; Dietmar W. Hutmacher Show abstract An integrated design, material and fabrication platform for engineering biomechanically and biologically functional soft tissues
  ACS Appl. Mater. Interfaces, 2017
  DOI: 10.1021/acsami.7b08617 - Status: Verlagsversion / published
  
  
  
  The development of advanced soft materials can be faciliated through bioinspired design methodologies. Translating the fibre-reinforcement approach of nature, biologically functional soft network composites with enhanced compressive mechanical properties have been achieved. However, design and fabrication concepts addressing the mechanical requirements of tissues which are predominantly functioning under tensile loading (e.g., skin, tendon, ligament, muscle, etc.) are under studied in the current literature. In this communication, to our knowledge for the first time we describe and validate a design library combined with a innovative biomaterials & 3D printing platform which meets the requirements for tissue engineering applications subjected to tensile loads. Herein, we present a library of fibre elements to be used as building blocks for the development of tailored fibrous networks. These fibrous networks are then combined with a tunable interpenetrating polymer network (IPN) system that mimics highly flexible natural extracellular matrices (ECMs). Our holistic design allows the selection and fabrication of customised reinforcing fibre networks and matrices to match both complex tissue-specific biomechanical and biological properties. We mechanically validate our approach through an exemplary soft network composite model which is charactarized to be flexible yet ~125 times stronger (E = 3.19 MPa) and ~100 times tougher (WExt = ~2000 kJ m-3) than its bare hydrogel counterpart.
  
  
  
• Bas, O.; De-Juan-Pardo, E.; Meinert, C.; D'Angella, D.; Baldwin, J.; Bray, L.; Wellard R.; Kollmannsberger, S.; Rank, E. Werner, C.; Klein, T.; Catelas I.; Hutmacher, D.W. Biofabricated soft network composites for cartilage tissue engineering
  Biofabrication, Biofabrication, 2017
  DOI: 10.1088/1758-5090/aa6b15 - Status: Verlagsversion / published
  
  
  
  
  
  
  
• D'Angella, D.; Zander, N.; Kollmannsberger, S.; Frischmann, F.; Rank, E.; Schröder, A.; Reali, A. Show abstract Multi-Level hp-Adaptivity and Explicit Error Estimation
  Advanced Modeling and Simulation in Engineering Sciences, pp. 1-18, Springer, 2016
  DOI: 10.1186/s40323-016-0085-5 - Status: Verlagsversion / published
  
  
  
  Recently, a multi-level hp-version of the Finite Element Method (FEM) was proposed to ease the difficulties of treating hanging nodes, while providing full hp-approximation capabilities. In the original paper, the refinement procedure made use of a-priori knowledge of the solution. However, adaptive procedures can produce discretizations which are more effective than an intuitive choice of element sizes h and polynomial degree distributions p. This is particularly prominent when a-priori knowledge of the solution is only vague or unavailable. The present contribution demonstrates that multi-level hp-adaptive schemes can be efficiently driven by an explicit a-posteriori error estimator. To this end, we adopt the classical residual-based error estimator. The main insight here is that its extension to multi-level hp-FEM is possible by considering the refined-most overlay elements as integration domains. We demonstrate on several two- and three-dimensional examples that exponential convergence rates can be obtained.
  
  
  

Conference Proceedings

• D'Angella, D.; Schiavo, C.V, Visconti, A.Tight upper bounds for polynomial multiplication
  In proceedings of the 6th WSEAS World Congress: Applied Computing Conference (ACC 2013). WSEAS (2013).

Conference Talks

• Kollmannsberger, S.; Carraturo, M.; D'Angella, D.; Auricchio, F.; Reali, A.; Rank, E. Accurate prediction of melt pool shapes in laser powder bed fusion by the non-linear temperature equation including phase changes
  In: Simulation in Additive Manufacturing, Rovereto, Italy, 2019
  
  
  
  
  
  
  
• Kollmannsberger, S.; Carraturo, M.; D'Angella, D.; Auricchio, F.; Özcan, A.; Reali, A.; Rank, E. Show abstract Multi-level finite elements of high-order for the simulation of melt pool sizes and cooling rates in metal additive manufacturing
  In: AM Bench conference, Geithersburg, Washington, USA, 2018
  
  
  
  The presentation addresses the numerical modelling of the benchmark AMB2018-02 where we take upon the challenge of verifying the melt pool geometry (CHAL-AMB2018-02-MP) and the cooling rate (CHAL-AMB2018-02-CR). We employ a variant of the numerical model presented in [1] and extend it to hierarchical B-Splines [2]. The principal idea is to use high-order refinements to resolve the region around the boundary of the weld pool with high accuracy. The numerical effort in parts of the domain remote to the laser impact are coarsened such that a computationally efficient model results.
  
  
  
• Davide D'Angella; Luca Coradello; Massimo Carraturo; László Kudela; Stefan Kollmannsberger; Ernst Rank; Alessandro Reali Locally Refined Isogeometric Analysis of Trimmed Shells
  In: The 13th World Congress in Computational Mechanics, 2018
  
  
  
  
  
  
  
• Davide D'Angella; Luca Coradello; Massimo Carraturo; László Kudela; Stefan Kollmannsberger; Ernst Rank; Alessandro Reali Trimming and Local Refinement for Isogeometric Shells Analysis
  In: 6th European Conference on Computational Mechanics (Solids, Structures and Coupled Problems) (ECCM 6) and the 7th European Conference on Computational Fluid Dynamics (ECFD 7), 2018
  
  
  
  
  
  
  
• Davide D'Angella; Stefan Kollmannsberger; Ernst Rank; Alessandro Reali Efficient Algorithms for the Extraction of (Truncated) Hierarchical B- Splines
  In: 3rd Conference on Isogeometric Analysis and Applications, 2018
  
  
  
  
  
  
  
• Kollmannsberger, S.; Özcan, A.; D'Angella, D.; Carraturo, M.; Kopp, P.; Zander, N.; Reali, A.; Auricchio, F.; Rank, E. Show abstract Computational Modelling of Metal Additive Manufacturing
  In: European Conference on Computational Mechanics, Glasgow, UK, 2018
  
  
  
  The numerical simulation of metal additive manufacturing bears numerous computational challenges. It is a thermo-mechanically coupled process in which material coefficients depend nonlinearly on the state of the material and the temperature. The energy input is highly localized which leads to strong temperature gradients and rapid changes of state in the material on growing computational domains. The large span of the involved spatial and the temporal scales call for highly efficient computational techniques. It is well known that hp-finite elements yield very accurate results for problems with strong gradients or even singular solutions. hp-finite elements are, therefore, an ideal candidate for the simulation of metal additive manufacturing. In this contribution, we present a computational framework which was specifically designed to resolve moving singularities and sharp fronts. Its core employs the multi-level hp-method for the resolution of strong gradients in the solution field. This is complemented by a spatially hierarchic management of material coefficients in the spirit of the finite cell method. We will discuss the computation of the metal additive manufacturing process and evaluate accuracy and efficiency of the presented computational approach by comparison to benchmark solutions.
  
  
  
• de Prenter, F.; Jomo, J.; Elhaddad, M.; D'Angella, D.; Kollmannsberger, S.; Verhoosel, C.; van Brummelen, H.; Rank, E. Preconditioned iterative solvers for the multi-level hp-adaptive finite cell method
  In: 6th European Conference on Computational Mechanics, Glasgow, United Kingdom, 2018
  
  
  
  
  
  
  
• Carraturo, M.; Özcan, A.; D'Angella, D; Kollmannsberger, S.; Rank, E.; Auricchio, F.; Reali, A. Thermal Simulations of Additive Manufacturing Processes using Multi-level Isogeometric Analysis
  In: World Congress of Computational Mechnaics, New York, USA, 2018
  
  
  
  
  
  
  
• Kollmannsberger, S.; Özcan, A.; Carraturo, M.; D'Angella, D.; Zander, N.; Auricchio, A.; Reali, A.; Rank, E. Verification of a multi-level model for the simulation of AM processes
  In: 89. Annual Meeting of the International Assosication of Applied Mathematics and Mechanics, Munich, Germany, 2018
  
  
  
  
  
  
  
• D'Angella, D.; Kollmannsberger, S.; Rank, E.; Reali, A. IGA Based on Extraction of (Truncated) Hierarchical B-Splines
  In: International Conference on Isogeometric Analysis, 2017
  
  
  
  
  
  
  
• Davide D'Angella; Onur Bas; Dietmar W. Hutmacher; Stefan Kollmannsberger; Alessandro Reali; Ernst Rank Simulation of Hydrogel Reinforced by 3D Printed Fibres
  In: Simulation for Additive Manufacturing, 2017
  
  
  
  
  
  
  
• D'Angella, D.; Kollmannsberger, S.; Rank, E.; Reali, A. The multi-level Bézier extraction
  In: International Conference on Computational Plasticity, 2017
  
  
  
  
  
  
  
• Zander, N.; D'Angella, D.; Bog, T.; Kollmannsberger, S.; Ruess, M.; Rank, E. Multi-level hp-FEM: dynamic discretizations with arbitrary hanging nodes for solid mechanics
  In: European Congress on Computational Methods in Applied Sciences and Engineering, Crete Island, Greece, 2016
  
  
  
  
  
  
  

• D’Angella, D.; Hughes, T.J.R.; Kollmannsberger, S.; Rank, E.; Reali, A. Reaction computations on trimmed locally refined meshes
  In: Seventh International Conference on Isogeometric Analysis (IGA 2019), 2019
  
  
  
  
  
  
  

Poster

• D. D'Angella; L. Coradello; M. Carraturo; L. Kudela; S. Kollmannsberger; E. Rank; A. Reali Trimming and Local Refinement for Isogeometric Shells Analysis
  In: HOFEIM2019, 2019
  
  
  
  
  
  
  
• Onur Bas; Elena M. De-Juan-Pardo; Davide D'Angella; Stefan Kollmannsberger; Alessandro Reali; Ernst Rank; D. W. Hutmacher Rational design and fabrication of soft network composites for soft tissue engineering applications: a numerical model-based approach
  In: TERMIS 5th World Congress, Kyoto, Japan, 2018
  
  
  
  
  
  
  
• Davide D'Angella; Nils Zander; Stefan Kollmannsberger; Felix Frischmann; Andreas Schröder; Ernst Rank; Alessandro Reali Explicit Error Estimation and Multi-Level hp-Adaptivity
  In: Seventh International Workshop on High-Order Finite Element and Isogeometric Methods, Jerusalem, Israel, 2016
  
  
  
  
  
  
  

Theses

• D'Angella, D. Show abstract A Posteriori Error Estimator for the Multi-Level hp-Finite Element Method
  Master's thesis, Technische Universität München, 2015
  
  
  
  This works aims to investigate the applicability of residual-based error estimators to two variants of the Finite Element Method: the multi-level Finite Element Method and the Finite Cell's Method (FCM). The study is performed both theoretically and numerically, showing excellent results for the Multi-Level Finite Element Method in the context of Poisson's and linear elastic problems. Furthermore, the analysis carried out in the context of the FCM furnishes a starting point for further developments and investigations on how to estimate the error in case of a non-conforming discretization.