检索结果-内蒙古大学图书馆

27th CIRP Life Cycle Engineering Conference, LCE 2020

作者： Herrmann, Christoph Büth, Lennart Juraschek, Max Abraham, Tim Schäfer, Lothar Chair of Sustainable Manufacturing and Life Cycle Engineering Institute of Machine Tools and Production Technology Technische Universität Braunschweig Germany Fraunhofer Institute for Surface Engineering and Thin Films Braunschweig Germany

Urbanization and the limited environmental carrying capacity of our planet are crucial challenges for human kind. Industrial value creation and the production of goods have a significant role in the worldwide emissions pattern. A biologically oriented conception of technical systems with the goal of a sustainable added value is summarized as "biological transformation". By bringing together the concentration of consumption, waste generation and more, in urban areas, with the biologicalisation of industrial value creation an opportunity arises to actively create bio-based positive urban production. Based on the principles of the biological transformation a framework is derived, stretching the design space between spatial urban levels and production life cycle stages, thereby fostering positive bio-based urban production. The design space is then applied, allocating current realization and envisioned cases as well as giving recommendations for future research topics. © 2020 The Author(s). Published by Elsevier B.V.

关键词： Industrial emissions

来源：评论

学校读者我要写书评

暂无评论

CFD simulation to optimize the internal coolant channels of an additively manufactured milling tool

引用

Procedia CIRP 2021年 102卷 234-239页

作者： Christoph Zachert Hui Liu Thomas Lakner Daniel Schraknepper Thomas Bergs Laboratory for Machine Tools and Production Engineering (WZL) of RWTH University Campus-Boulevard 30 52074 Aachen Germany Fraunhofer Institute for Production Technology (IPT) Steinbachstraße 17 52074 Aachen Germany

The emerging heat in machining processes has a negative influence on tool wear. Part of the thermal energy is dissipated by supplying cutting fluid. The cutting fluid supply through conventionally manufactured, sharp-edged coolant channels leads to non-optimal cutting fluid flow behavior. By optimizing the coolant channel geometry using computational fluid dynamics (CFD) simulation, the cutting fluid flow inside the coolant channel can be optimized. The simulation approach increased the cutting fluid volumetric flow rate by 24 %. Due to the volumetric flow rate increase the cooling effect is improved, which results in longer tool life.

关键词： CFD Additive manufacturing Milling tool Internal coolant channel

来源：评论

学校读者我要写书评

暂无评论

Surface interactions of SiO 2 -nanofluids with 100Cr6-steel during machining

引用

Procedia CIRP 2022年 108卷 13-18页

作者： Christian Köhn Robar Arafat Annelise Jean-Fulcrand Tim Abraham Christoph Herrmann Georg Garnweitner Institute for Particle Technology Technische Universität Braunschweig Volkmaroder Straße 5 38104 Braunschweig Germany Institute of Machine Tools and Production Technology Chair of Sustainable Manufacturing & Life Cycle Engineering Technische Universität Braunschweig Langer Kamp 19b 38106 Braunschweig Germany Fraunhofer Institute of Surface Engineering and Thin Films (IST) Bienroder Weg 54 E 38106 Braunschweig Germany

Nanofluids consisting of nanoscale particles in a carrier medium are increasingly used as cutting fluids in minimum quantity lubrication (MQL) due to their enhanced cooling and lubricating properties. These improvements have already been demonstrated, but a fundamental understanding of the underlying mechanisms and particle-surface interactions is still lacking. Therefore, in this research nanofluids are used in tribological applications and the interactions of the particles with the workpiece surface are investigated. A tribological test rig is used and various SiO 2 -based nanofluids are applied under different machining conditions. Special attention is given to the deposition of the particles on the workpiece surface.

关键词： nanofluids grinding surface interactions

来源：评论

学校读者我要写书评

暂无评论

Advanced calculation of the stress distribution in milling tools during cutting under consideration of residual stresses and tool wear

引用

Procedia CIRP 2021年 102卷 19-24页

作者： Daniel Schraknepper Bingxiao Peng Thomas Bergs Laboratory for Machine Tools and Production Engineering (WZL) of RWTH Aachen University Campus-Boulevard 30 52074 Aachen Germany Fraunhofer Institute for Production Technology IPT Steinbachstrasse 17 52074 Aachen Germany

Milling is an irreplaceable technology for finishing turbomachinery components made of nickel-based alloys. Cutting tools in milling are exposed to high thermomechanical loads causing tool wear or ultimately tool failure. The initial condition of the tool’s surface layer determines the propagation of tool wear. “Surface layer” denotes the zone near the tool surface, which is affected mechanically, thermally, and chemically during the manufacturing process of the tool (e.g. due to grinding, polishing). So far, only limited knowledge is available on the specific effects of wear-induced changes in tool geometry as well as of residual stresses on the distribution of stresses in the cutting wedge of milling tools. This publication presents a method to consider residual stresses of cutting tools and tool wear in a 2D FEM chip formation model for detailed analysis of certain tool failure phenomena in the milling process. In order to represent a depth distribution of residual stresses in the surface layer of the uncoated tool in the simulation, residual stress measurements at grinded milling tools were performed. Tool wear was taken into account by adapting the geometry of the cutting tool. The geometry changes were based on measurements of the width of the flank wear land and of the cutting edge radius. Principal stresses and von Mises equivalent stress distribution were analyzed. The described method may improve the understanding of surface layer effects on tool life of milling tools. With decreasing chip thickness, a second, more localized zone of tensile stresses was formed at the rake face subsurface, which can be critical in terms of fracture. With compressive residual stresses and with increased flank wear, these critical tensile stresses were reduced or even eliminated.

关键词： cutting tools tool wear stress distribution coupled Eulerian-Lagrangian FEM

来源：评论

学校读者我要写书评

暂无评论

Development of a voxelization tool for the calculation of vector-based workpiece representations

引用

Procedia CIRP 2021年 100卷 7-12页

作者： Thomas Bergs Oliver Henrichs Marcel Wilms Marcel Prümmer Kristian Arntz Fraunhofer Institute for Production Technology IPT Steinbachstr 17 52074 Aachen Germany Laboratory for Machine Tools and Production Engineering (WZL) of RWTH Aachen University Campus-Boulevard 30 52074 Aachen Germany

While voxelization techniques are quite common in domains like medical imaging and computer games, they still have a lot of untapped potential when applied to CAD-models. As a discretized 3D representation, they have a significant potential for new approaches in the fields of knowledge management, workpiece classification and subsequently process planning – especially when enriched with Product Manufacturing Information (PMI). We developed a voxelization tool for colored 3D-mesh representations of workpiece geometries that allows for the structured, dimensionality-reducing storage of geometry information and PMI. The tool creates voxel-representations of triangular mesh representations by recursively splitting the space in which a mesh representation resides into eight equal cubes and checking for intersections with the mesh. If such a cube intersects with the mesh, it is again split. This process continues until a threshold cube size or recursion depth is reached. After termination, the voxelized 3D model is represented by the subset of resulting cubes containing exactly the cubes intersecting with the model’s surface. Additional functionalities have been implemented to accommodate data-centric use cases; that is, for watertight, closed meshes the tool discriminates inside and outside voxels and can include them accordingly. The calculated voxelization can also be arbitrarily sampled to a fixed voxel count – allowing to represent the 3D model by a vector of fixed length. This, for example, enables the application of AI/machine Learning methods, the training of which typically requires a large amount of input vectors of a fixed length. Finally, we developed a plugin for the CAD application software Rhinoceros© that uses its 3D-canvas to display calculated voxelizations for visualization purposes. Going forward, data-centric applications can use workpiece information encoded inside the voxelization representation for a multitude of purposes such as similarity search

关键词： voxelization classification CAD dimensionality reduction

来源：评论

学校读者我要写书评

暂无评论

Current Insights into the Investigations on a New Motor Principle with Radially Laminated Stator Sheets, Concentrated Windings and Flux Barriers

Current Insights into the Investigations on a New Motor Prin...

引用

International Electric Drives Production Conference (EDPC)

作者： Alena Babl Mirko Bach Katrin Schubert Dieter Gerling Verena Kräusel Michaela Gedan-Smolka Chair of Electrical Drives and Actuators Bundeswehr University Munich Neubiberg Germany Fraunhofer Institute for Machine Tools and Forming Technology Chemnitz Germany Institut Polymerwerkstoffe Leibniz-Institut für Polymerforschung Dresden e. V. Dresden Germany

ISBN: (纸本)9781665418102

In the wake of the Paris Climate Agreement and the world wide obligation to reduce CO 2 emissions, products and their manufacturing processes must be optimized in order to reduce resource consumption. This particularly concerns the topic of electric drives and machines. Regarding machines, one possibility to achieve this goal is the use of so-called flux barriers. This working concept offers further possibilities for structural optimization, such as radial lamination of the sheets, which then allows the use of grain-oriented electrical steel. Both mentioned principles increase the efficiency of the machine to a high degree and reduce manufacturing costs, as the iron losses are lessened and the material utilization is raised. This paper presents recent investigations of the use of grain-oriented electrical steel sheets for novel, radially laminated stators for electric motors with concentrated windings and flux barriers. The focus is on the analysis of the electromagnetic properties of the electrical sheets before and after forming, their coating and the operating characteristics of the planned demonstrator machine. Recent findings in the area of the technical implementation of the demonstrator machine and its electromagnetic design with the aid of FEM simulation are presented. Furthermore, challenges are evaluated with regard to eddy currents that arise due the innovative design. Finally, recommendations for further proceeding are derived and the next steps are explained.

关键词： Lamination Windings Production Stators Manufacturing Finite element analysis Steel

来源：评论

学校读者我要写书评

暂无评论

Methodology for integrated additive-subtractive process chain generation

引用

Procedia CIRP 2021年 100卷 199-204页

作者： Moritz Wollbrink Tammo Dannen Kristian Arntz Marcel Prümmer Thomas Bergs Fraunhofer Institute for Production Technology IPT Steinbachstr 17 52074 Aachen Germany Laboratory for Machine Tools and Production Engineering (WZL) of RWTH Aachen University Campus-Boulevard 30 52074 Aachen Germany

The production share of laser powder bed fusion increases in industrial application and single piece and small series production are core markets. Still, many process steps in the field of additive manufacturing are manually operated, especially in post-processing. Additionally, it is not possible to achieve tight dimensional tolerances or low surface roughness which are necessary for typical mechanical parts. Hence, a process chain has to be set up to combine the design flexibility and function integration capabilities of AM with further machining technologies to achieve workpiece requirements. As L-PBF has some particular properties and process parameters influencing post-processing, an individual approach for process chain generation is needed. These properties and parameters are, in particular, support structures and free positioning options within the build chamber of the AM machine. Both properties have a major influence to post-processing and have to be addressed in machine selection, clamping options, processing steps and workpiece description. The approach shows how an additive manufactured workpiece can be described taking into account the complex part consisting of workpiece, support structures and substrate plate. Further, kinematic limitations for further processing are added as meta-information and workpiece requirements and machine performances are compared for a manufacturing process selection for further processing. Based on technological and economical parameters a manufacturing process selection is performed. Finally, improved parameters are suggested to optimize the L-PBF process with regard to further processing. So, the L-PBF process design can combine AM parameters with further processing parameters to improve the whole process chain. The methodology shall be implemented in a software tool to simplify the practical application.

关键词： Additive manufacturing post-processing further processing L-PBF machining process chain methodology

来源：评论

学校读者我要写书评

暂无评论

Potentials of Bluetooth Low Energy Beacons for order tracing in single and small batch production

引用

Procedia CIRP 2021年 97卷 202-210页

作者： Hannes Elser Philip Jongebloed Daniel Buschmann Max Ellerich Robert H. Schmitt Laboratory for Machine Tools and Production Engineering WZL of RWTH Aachen University Campus-Boulevard 30 52074 Aachen Germany Fraunhofer Institute for Production Technology IPT Steinbachstrasse 17 52074 Aachen Germany

The quality of production planning and control in production companies largely depends on the accuracy of the database regarding the status quo of the production process, as well as the time required for each production step. Especially in single and small batch production, it is difficult to create a reliable database due to the large product spectrum and the variation in the production process. For this reason, this paper examines the potential of Bluetooth Low Energy (BLE) Beacons to create a low-cost real-time locating system (RTLS). In comparison to other existing RTLS solutions like RFID, BLE stands out through very low hardware costs and a high compatibility to almost every mobile device. Through a signal strength based approach in combination with probabilistic neural networks, the RTLS has been able to achieve a positioning accuracy with a mean absolute error of up to 0,74 m in an industry-like environment.

关键词： Manufacturing Assembly Production planning and control Bluetooth Low Energy BLE Beacon Order tracing

来源：评论

学校读者我要写书评

暂无评论

Digital transformation of CAR-T cell therapy – challenges and potential for Industry 4.0

引用

Procedia CIRP 2023年 120卷 1034-1040页

作者： Simon Hort Carmen Sanges John J.L. Jacobs Michael Hudecek Robert H. Schmitt Fraunhofer Institute for Production Technology IPT Steinbachstr. 17 52074 Aachen Germany Lehrstuhl für Zelluläre Immuntherapie Medizinische Klinik und Poliklinik II Universitätsklinikum Würzburg Würzburg Germany Clinical Care and Research ORTEC BV Zoetermeer The Netherlands Laboratory for Machine Tools and Production Engineering (WZL) of RWTH Aachen University Campus-Boulevard 30 52074 Aachen Germany

With the approval of CAR-T cell therapy as a treatment for acute leukemia and lymphoma in 2018, the first advanced therapy medicinal product (ATMP) came onto the market. ATMPs are cell- and gene-based products and very promising therapies for the successful treatment of various hereditary diseases and cancers. In recent years, more ATMPs have been approved and a strong increase is expected considering current clinical trial numbers. However, CAR-T cell production still poses great challenges. The CAR-T treatment is very costly for approved products (approx. 400.000 $). Most of the associated costs are due to the expensive manufacturing processes. Furthermore, autologous CAR-T cell therapy is limited in its scalability by a patient-specific make-to-order approach which makes economic production difficult. To make CAR-T cell products and other ATMP available to a large number of patients, the complex multi-step manufacturing process must be further developed and the potential for automation and digitalization exploited. Therefore, this article provides an analysis of CAR-T cell production focusing on characteristics, challenges, and optimization potential. For strategic guidance in the digital transformation, a systematic approach, based on the Industry 4.0 maturity index, is introduced categorizing challenges and use cases into six stages.

关键词： CAR-T ATMP immunology Industry 4.0 Pharma 4.0 advanced therapies Industry 4.0 maturity index digital transformation

来源：评论

学校读者我要写书评

暂无评论

Integration of forming Manufacturing technology into the Component Production of Innovative Electric Motor Concepts

Integration of Forming Manufacturing Technology into the Com...

引用

International Electric Drives Production Conference (EDPC)

作者： Mirko Bach Alena Babl Dieter Gerling Fraunhofer Institute for Machine Tools and Forming Technology Chemnitz Germany Chair of Electrical Drives and Actuators Bundeswehr University Munich Neubiberg Germany

ISBN: (数字)9781728184586

ISBN: (纸本)9781728196145

Constantly increasing demands on production technology, such as sustainability and climate protection, require continuous optimization or even new development of production processes and designs, including in the field of electrical engineering. For this reason, it is also necessary to exploit the potential of various manufacturing technologies in order to achieve higher efficiency of the running machines. One way to achieve this goal is the application-optimized use of forming technology, which is less material-intensive due to its characteristics compared to, for example, cutting technology. Its use also allows better utilization of the special properties of electrical steel used in electrical machine construction or increases the so-called slot filling factor of electrical ***, motor stators consist of axially stacked, non-grain-oriented electrical steel (ngo), in whose motor slots coils of wound round wire are placed. The grain orientation of the sheets used has an influence on the amount of iron losses of the motor. With the use of round wire for the electric coils, only a slot filling factor of approx. 65 % can be achieved and thus potential for increasing the magnetic field of the coil is available. In order to achieve a higher slot filling factor, it is necessary to adapt the cross-sectional shape of the conductor material to the corresponding installation position by means of *** the present paper a novel approach for stator design with so-called flux barriers and thus the possibility of using radially laminated, grain-oriented plates are presented and the latest research results are shown. In addition current measurement results for the forming technical optimization of the increase of the slot filling factor of electrical coils with adapted conductor cross sections are presented and discussed.

关键词： Coils Electric potential Wires Production Stators Filling Manufacturing

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：