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The purpose of this paper is to present some of the key achievements. At DLR, a sophisticated interdisciplinary aircraft design process is being developed, using the CPACS data format (Nagel et al., 2012; Scherer and Kohlgrüber, 2016) as a means of exchanging results. Within this process, TRAFUMO (Scherer et al., 2013) (transport aircraft fuselage model), built on ANSYS and the Python programming language, is the current tool for automatic generation and subsequent sizing of global finite element fuselage models. Recently, much effort has gone into improving the tool performance and opening up the modeling chain to further finite element solvers.

Much functionality has been shifted from specific routines in ANSYS to Python, including the automatic creation of global finite element models based on geometric and structural data from CPACS and the conversion of models between different finite element codes. Furthermore, a new method for modeling and interrogating geometries from CPACS using B-spline surfaces has been introduced.

Several new modules have been implemented independently with a well-defined central data format in place for storing and exchanging information, resulting in a highly extensible framework for working with finite element data. The new geometry description proves to be highly efficient while also improving the geometric accuracy.

The newly implemented modules provide the groundwork for a new all-Python model generation chain, which is more flexible at significantly improved runtimes. With the analysis being part of a larger multidisciplinary design optimization process, this enables exploration of much larger design spaces within a given timeframe.

In the presented paper, key features of the newly developed model generation chain are introduced. They enable the quick generation of global finite element models from CPACS for arbitrary solvers for the first time.

A method for the prediction of solder joint cycle life in surface‐mount assemblies is presented, based on the conversion of plastic solder shear strain into cycle life by means of an equation derived by Engelmaier. The paper introduces a different analytical procedure for the determination of solder joint shear strain. Shear strain is normally calculated from temperature and TCE differentials between package and interconnect board without consideration of elastic deformations. The suggested method derives average plastic shear strain of the solder joint at maximum temperature excursion from finite‐element analysis of a simple model consisting of an interconnect board, a solder joint and a package. All materials in the model have linear (elastic) properties, except solder which has non‐linear (elastic/plastic) characteristics. The solder stress/strain curve is described to the finite‐element programme with temperature‐dependent bilinear approximations. The solder joint is modelled as a single finite element so that only one value is computed for the plastic shear strain in the solder joint. This value represents the average shear strain which is converted into solder joint cycle life. The cycle life predictions with the finite‐element method are confirmed by cycling results obtained on actual hardware. The described method can serve as a design tool in the optimisation of surface‐mount assemblies. The procedure can help to define accelerated temperature cycling conditions.

In recent years, developments in the field of lightweight armour have been of primary importance to the defence industry. This necessity has led to many organisations adopting composite armours comprising both the traditional heavy armours and new lighter weight ceramic armours. The numerical modelling of metal based armour systems has been well documented over the years using purely continuum based methods; and also the modelling of brittle systems using discrete element methods, therefore it is the objective of this paper to demonstrate how a coupled finite and discrete element approach, can be used in the further understanding of the quantitative response of ceramic systems when subjected to dynamic loadings using a combination of adaptive continuum techniques and discrete element methods. For the class of problems encountered within the defence industry, numerical modelling has suffered from one principal weakness; for many applications the associated deformed finite element mesh can no longer provide an accurate description of the deformed material, whether this is due to large ductile deformation, or for the case of brittle materials, degradation into multiple bodies. Subsequently, two very different approaches have been developed to combat such deficiencies, namely the use of adaptive remeshing for the ductile type materials and a discrete fracture insertion scheme for the modelling of material degradation. Therefore, one of the primary objectives of this paper is to present examples demonstrating the potential benefits of explicitly coupling adaptive remeshing methods to the technique of discrete fracture insertion in order to provide an adaptive discontinuous solution strategy, which is computationally robust and efficient.

Introduces papers from this area of expertise from the ISEF 1999 Proceedings. States the goal herein is one of identifying devices or systems able to provide prescribed performance. Notes that 18 papers from the Symposium are grouped in the area of automated optimal design. Describes the main challenges that condition computational electromagnetism’s future development. Concludes by itemizing the range of applications from small activators to optimization of induction heating systems in this third chapter.

The boundary element and finite element methods have been combined so as to allow for arbitrary intermixing of element types in modelling problems of axisymmetric thermoelasticity, including body forces due to rotational inertia. The formulation for combining the methods is given, and a general purpose, finite element program has been generalized to accommodate both types of elements and to determine stresses within and on the boundary of boundary‐type elements after the primary solution for the displacements. Example problems demonstrate the validity and accuracy of the technique.

Gives a bibliographical review of the finite element meshing and remeshing from the theoretical as well as practical points of view. Topics such as adaptive techniques for meshing and remeshing, parallel processing in the finite element modelling, etc. are also included. The bibliography at the end of this paper contains 1,727 references to papers, conference proceedings and theses/dissertations dealing with presented subjects that were published between 1990 and 2001.

Over the past few years, the number of related research to additive manufacturing (AM) has risen. The selective composite formation (SCF) can also be found among the new technologies that were developed. This technology was first introduced in 2013, and because of its innovative character, there are still many challenges to be overcome. Therefore, the main aim of this study is to present a finite element method which allows to investigate the processing of the material during the selective formation of a composite material based on cellulose and acrylic.

In the beginning, we introduced a brand new finite element method approach which is based on light transmittance network and photopolymerisation in transient state. This method is mainly characterised by internal light absorption, transversal reflectance, light transmittance coefficient and photopolymerisation kinetics. The authors defined experimentally the main model coefficients besides investigating the formation of composite material in six case studies. The main variables evaluated in those studies were the number of layers and the number of lines. By the end, the degree of polymer conversion and the preliminary evaluation of adherence between layers were identified in addition to the formation profile of composite material.

The presented method evidence that the SCF resulted in a profile of polymerisation which is different from profiles found in vat polymerisation processes. It was shown that the light diffraction increases polymerisation area to outside of laser limits and reduces the penetration depth. It was also exposed that the selective formation of composite material on the top layer interferes with the polymerisation of previous layers and might increase the polymerised area in about 25 per cent per layer. By the end, adherence between layers was evidenced because of a high-pass filter that limited polymer conversion to over 60 per cent. In this case, the adherence between the top layers was provided by the interface between layers, while the deeper layers resulted in a solid formed by composite.

This paper presents research results related to a very new AM technology and also proposes a new method to characterise this concept. Because of this new analytic approach, the process planning can be simulated and optimised, in addition to being a useful tool for other researches related to photocurable polymers and AM technologies.

Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the theoretical as well as practical points of view. The range of applications of FEMs in this area is wide and cannot be presented in a single paper; therefore aims to give the reader an encyclopaedic view on the subject. The bibliography at the end of the paper contains 2,025 references to papers, conference proceedings and theses/dissertations dealing with the analysis of beams, columns, rods, bars, cables, discs, blades, shafts, membranes, plates and shells that were published in 1992‐1995.

The general structure of geometrically‐based automatic finite element modelling systems is discussed. The development of a specific system employing the modified‐quadtree and modified‐octree mesh generators is presented. The application of this approach to metal forming analysis is then given.

Discusses the 27 papers in ISEF 1999 Proceedings on the subject of electromagnetisms. States the groups of papers cover such subjects within the discipline as: induction machines; reluctance motors; PM motors; transformers and reactors; and special problems and applications. Debates all of these in great detail and itemizes each with greater in‐depth discussion of the various technical applications and areas. Concludes that the recommendations made should be adhered to.