Grid-Free Surface-Based Geological Modelling using Subdivisions Surfaces and NURBS – Advantages for Geothermal Applications

Mapping Intimacies ◽

10.5194/egusphere-egu21-10114 ◽

2021 ◽

Author(s):

s.Mohammad Moulaeifard ◽

Denise Degen ◽

Florian Wellmann

Keyword(s):

Finite Element ◽

Free Surface ◽

Computer Aided Design ◽

Cost Effective ◽

Subdivision Surfaces ◽

Grid Cells ◽

Geological Structures ◽

Geological Modelling ◽

Low Dimensional ◽

Modelling Methods

Pragmatic and cost-effective representations of geological structures and features (e.g., heterogeneities, faults and folds) in full 3-D geological models are challenging. Implementations are highly dependent on the flexibility of the representation method. We investigate the use of parametric surface-based geological modelling methods for the purpose of low-dimensional model representations. Specifically, we focus on two grid-free and controllable parametric surfaced-based modelling methods: NURBS and subdivision surfaces. NURBS are the standard method in Computer-Aided Design (CAD) and have been used in geological reservoir modelling before. Subdivision surfaces are a common representation in the gaming and animation industry. They are very interesting as they can support watertight modelling and arbitrary topology (preserving the relationship between different parts of the model). However, this method is, to date, rarely used in geological modelling.Unlike implicit modelling, parametric surfaced-based modelling is a grid-free representation and exploits the boundary surfaces of the model. Also, the geological features (e.g., heterogeneities, faults, folds) can be represented by there bounding surfaces instead of grid-cells. Therefore, they do not suffer from the limitation of grid cells (e.g., Stair-stepping), which are often present in implicit representations.We discuss the advantages and shortcomings of both NURBS and subdivision surfaces for geological modelling. Furthermore, we investigate the approximation of geological structures by subdivision surfaces in this presentation. The approximated models are watertight (closed), controllable with few control points, smooth, and have less than 5% of the number of the vertices of the original model. Reducing the number of vertices of the model while preserving the topology can decrease the cost of both modelling and simulations. As the final step, we present the advantages of grid-free surface-based geological modelling for thermal finite element analyses by using a state-of-the-art finite-element solver, namely the MOOSE framework

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Computer-Aided Static and Dynamic Properties Design of the Frame of Electrical Slag Founding Furnace

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.297-300.2261 ◽

2005 ◽

Vol 297-300 ◽

pp. 2261-2265 ◽

Cited By ~ 1

Author(s):

Li Gang Qu ◽

Jian Hui Li ◽

Hang Gao

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Computer Aided Design ◽

Dynamic Properties ◽

Cost Effective ◽

Frame Structure ◽

Computational Time ◽

Element Analysis ◽

Seamless Integration ◽

Computer Aided

The double-vertical-column frame component, 8780mm high, is the key structure of Electrical Slag Founding Furnace (ESFF). Due to its structural complexity and crucial functional role in the entire equipment, the frame structure is actually the most sensitive part of cost-effective manufacturing. Properties design, in which both static and dynamic properties are analyzed in order to meet the functionality requirement, is widely believed as important as other production processes, such as requirement identification, conceptualization, DFM and so on. And its deterministic role in cost effective manufacturing has been discussed in many historical literatures. Finite Element Analysis (FEA), one of most powerful engineering tool, has long been employed in designing of the frame component aiming to reduce computational time and improve computational precision, either in presence of separated tool or as an integrated utility in CAD systems, for a long time. However seamless integration FEM into Computer-Aided-Design is still a challenging topic and one of the bottlenecks of cost-effective design recognized by scientists in the past. Based on a 3D solid model created with the CAD-system-compatible software SolidWorks, Finite Element Analysis (FEA) of the Furnace frame structure was carried out, which provided easily utilized data for the successive manufacturing processes as well as near-instantaneous feedbacks to designing process.

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CAD Of Anticorrosive Protection Of Steel Structures

Promyshlennoe i Grazhdanskoe Stroitel stvo ◽

10.33622/0869-7019.2019.09.18-23 ◽

2019 ◽

pp. 18-23

Keyword(s):

Protective Coating ◽

Computer Aided Design ◽

Steel Structures ◽

Cost Effective ◽

Operating Conditions ◽

Computational Tool ◽

Protection Method ◽

Cost Effective Method ◽

The Cost ◽

Aided Design

The choice of cost-effective method of anticorrosive protection of steel structures is an urgent and time consuming task, considering the significant number of protection ways, differing from each other in the complex of technological, physical, chemical and economic characteristics. To reduce the complexity of solving this problem, the author proposes a computational tool that can be considered as a subsystem of computer-aided design and used at the stage of variant and detailed design of steel structures. As a criterion of the effectiveness of the anti-corrosion protection method, the cost of the protective coating during the service life is accepted. The analysis of existing methods of steel protection against corrosion is performed, the possibility of their use for the protection of the most common steel structures is established, as well as the estimated period of effective operation of the coating. The developed computational tool makes it possible to choose the best method of protection of steel structures against corrosion, taking into account the operating conditions of the protected structure and the possibility of using a protective coating.

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Faculty Opinions recommendation of Specific evidence of low-dimensional continuous attractor dynamics in grid cells.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.718030887.793487681 ◽

2013 ◽

Author(s):

Nachum Ulanovsky ◽

Dori Derdikman

Keyword(s):

Grid Cells ◽

Attractor Dynamics ◽

Low Dimensional

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Metal Forming and the Finite-Element Method

10.1093/oso/9780195044027.001.0001 ◽

1989 ◽

Cited By ~ 25

Author(s):

Shiro Kobayashi ◽

Soo-Ik Oh ◽

Taylan Altan

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Metal Forming ◽

Computer Aided Design ◽

The Finite Element Method ◽

Forming Technology ◽

Computer Aided ◽

Deformation Mechanics ◽

Aided Design ◽

Element Method

The application of computer-aided design and manufacturing techniques is becoming essential in modern metal-forming technology. Thus process modeling for the determination of deformation mechanics has been a major concern in research . In light of these developments, the finite element method--a technique by which an object is decomposed into pieces and treated as isolated, interacting sections--has steadily assumed increased importance. This volume addresses advances in modern metal-forming technology, computer-aided design and engineering, and the finite element method.

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Development of a numerical compensation framework for geometrical deviations in bulk metal forming exploiting a surrogate model and computed compatible stresses

International Journal of Material Forming ◽

10.1007/s12289-020-01603-7 ◽

2021 ◽

Author(s):

Lorenzo Scandola ◽

Christoph Büdenbender ◽

Michael Till ◽

Daniel Maier ◽

Michael Ott ◽

...

Keyword(s):

Finite Element ◽

Surrogate Model ◽

Metal Forming ◽

Computer Aided Design ◽

Transition Process ◽

Reference Points ◽

Compensation Method ◽

Tool Geometry ◽

Bulk Metal ◽

Bulk Metal Forming

AbstractThe optimal design of the tools in bulk metal forming is a crucial task in the early design phase and greatly affects the final accuracy of the parts. The process of tool geometry assessment is resource- and time-consuming, as it consists of experience-based procedures. In this paper, a compensation method is developed with the aim to reduce geometrical deviations in hot forged parts. In order to simplify the transition process between the discrete finite-element (FE) mesh and the computer-aided-design (CAD) geometry, a strategy featuring an equivalent surrogate model is proposed. The deviations are evaluated on a reduced set of reference points on the nominal geometry and transferred to the FE nodes. The compensation approach represents a modification of the displacement-compatible spring-forward method (DC-SF), which consists of two elastic FE analyses. The compatible stress originating the deviations is estimated and subsequently applied to the original nominal geometry. After stress relaxation, an updated nominal geometry of the part is obtained, whose surfaces represent the compensated tools. The compensation method is verified by means of finite element simulations and the robustness of the algorithm is demonstrated with an additional test geometry. Finally, the compensation strategy is validated experimentally.

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The Force Cone Method Applied to Explain Hidden Whirls in Tribology

Materials ◽

10.3390/ma14143894 ◽

2021 ◽

Vol 14 (14) ◽

pp. 3894

Author(s):

Claus Mattheck ◽

Christian Greiner ◽

Klaus Bethge ◽

Iwiza Tesari ◽

Karlheinz Weber

Keyword(s):

Finite Element ◽

Free Surface ◽

Simple Model ◽

Alternative Explanation ◽

Model Experiments ◽

Complex Processes ◽

Buried Interfaces ◽

Internal Structures ◽

Ideal Tool ◽

Acting Force

In tribologically loaded materials, folding instabilities and vortices lead to the formation of complex internal structures. This is true for geological as well as nanoscopic contacts. Classically, these structures have been described by Kelvin–Helmholtz instabilities or shear localization. We here introduce an alternative explanation based on an intuitive approach referred to as the force cone method. It is considered how whirls are situated near forces acting on a free surface of an elastic or elastoplastic solid. The force cone results are supplemented by finite element simulations. Depending on the direction of the acting force, one or two whirls are predicted by the simplified force cone method. In 3D, there is always a ring shaped whirl present. These modelling findings were tested in simple model experiments. The results qualitatively match the predictions and whirl formation was found. The force cone method and the experiments may seem trivial, but they are an ideal tool to intuitively understand the presence of whirls within a solid under a tribological load. The position of these whirls was found at the predicted places and the force cone method allows a direct approach to understand the complex processes in the otherwise buried interfaces of tribologically loaded materials.

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An Innovative and Cost-Advantage CAD Solution for Cubitus Varus Surgical Planning in Children

Applied Sciences ◽

10.3390/app11094057 ◽

2021 ◽

Vol 11 (9) ◽

pp. 4057

Author(s):

Leonardo Frizziero ◽

Gian Maria Santi ◽

Christian Leon-Cardenas ◽

Giampiero Donnici ◽

Alfredo Liverani ◽

...

Keyword(s):

Computer Aided Design ◽

Low Cost ◽

Cost Effective ◽

Varus Deformity ◽

Patient Specific ◽

Cubitus Varus ◽

Surgical Guide ◽

Traditional Procedure ◽

Custom Made ◽

Patient Specific Instruments

The study of CAD (computer aided design) modeling, design and manufacturing techniques has undergone a rapid growth over the past decades. In medicine, this development mainly concerned the dental and maxillofacial sectors. Significant progress has also been made in orthopedics with pre-operative CAD simulations, printing of bone models and production of patient-specific instruments. However, the traditional procedure that formulates the surgical plan based exclusively on two-dimensional images and interventions performed without the aid of specific instruments for the patient and is currently the most used surgical technique. The production of custom-made tools for the patient, in fact, is often expensive and its use is limited to a few hospitals. The purpose of this study is to show an innovative and cost-effective procedure aimed at prototyping a custom-made surgical guide for address the cubitus varus deformity on a pediatric patient. The cutting guides were obtained through an additive manufacturing process that starts from the 3D digital model of the patient’s bone and allows to design specific models using Creo Parametric. The result is a tool that adheres perfectly to the patient’s bone and guides the surgeon during the osteotomy procedure. The low cost of the methodology described makes it worth noticing by any health institution.

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Development of Nonlinear Finite Element Models of Mortar-Free Interlocked Single Block Column Subjected to Lateral Loading

Arabian Journal for Science and Engineering ◽

10.1007/s13369-021-05668-7 ◽

2021 ◽

Author(s):

Furqan Qamar ◽

Shunde Qin

Keyword(s):

Finite Element ◽

Failure Load ◽

Cost Effective ◽

Nonlinear Finite Element ◽

World Population ◽

Bond Failure ◽

Lateral Resistance ◽

Lateral Strength ◽

Parametric Studies ◽

Single Block

AbstractAround the globe, the need for additional housing, due to the increase in world population, has led to the exploration of more cost effective and environmentally friendly forms of construction. Out of many technologies found, mortar-free interlocked masonry systems were developed to eliminate the deficiency of traditional masonry. For such systems against earthquakes, lateral resistance can be enhanced with plaster. But there is a need to further improve the performance of plaster in mortar-free interlocking walls for better ductility. The objective of this study is to develop nonlinear finite element (NLFE) models to explore the likely failure mechanism (e.g. bond failure) of such systems and to do parametric studies more cheaply than constructing many walls. Lateral failure load, load–displacement curves and crack patterns were compared with the experimental results. Parametric studies involving variation in block and plaster compressive strength and plaster thickness were undertaken using TNO DIANA NLFE models. A 150% increase in thickness of plaster only resulted in 28% increase in failure load, and column thickness can be reduced to theoretical 25 mm of blocks with 8 mm of plaster and yet exceed the lateral strength of a 150-mm-thick unplastered column. A cost analysis was also carried out, based on NLFE models, and showed that fibrous plastered column with 25-mm-thickness blocks gave equivalent performance to the 150-mm-thick unplastered column with 67% cost saving.

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