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Soft Sensors for Property‑Controlled Multi‑Stage Press Hardening of 22MnB5

Automotive Innovation 2023年第3期6卷 352-363页

作者： Juri Martschin Malte Wrobel Joshua Grodotzki Thomas Meurer A.Erman Tekkaya Institute of Forming Technology and Lightweight Components TU Dortmund UniversityBaroper Str.30344227 DortmundGermany Institute of Mechanical Process Engineering and Mechanics Karlsruhe Institute of Technology(KIT)Hertzstr.1676187 KarlsruheGermany

In multi-stage press hardening,the product properties are determined by the thermo-mechanical history during the sequence of heat treatment and forming *** measure these properties and finally to control them by feedback,two soft sensors are developed in this *** press hardening of 22MnB5 sheet material in a progressive die,where the material is first rapidly austenitized,then pre-cooled,stretch-formed,and finally die bent,serves as the framework for the development of these *** provide feedback on the temporal and spatial temperature distribution,a soft sensor based on a model derived from the Dynamic mode decomposition(DMD)is *** model is extended to a parametric DMD and combined with a Kalman filter to estimate the temperature(-distribution)as a function of all process-relevant control *** soft sensor can estimate the temperature distribution based on local thermocouple measurements with an error of less than 10°C during the process-relevant time *** the online prediction of the final microstructure,an artificial neural network(ANN)-based microstructure soft sensor is *** part of this,a transferable framework for deriving input parameters for the ANN based on the process route in multi-stage press hardening is presented,along with a method for developing a training database using a 1-element model implemented with LS-Dyna and utilizing the material model Mat248(PHS_BMW).The developed ANN-based microstructure soft sensor can predict the final microstructure for specific regions of the formed and hardened sheet in a time span of far less than 1 s with a maximum deviation of a phase fraction of 1.8%to a reference simulation.

关键词： Press hardening Property control Soft sensor Artificial neuronal network Dynamic mode decomposition

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Tailoring the Hardness in Multi-stage Press Hardening of 22MnB5 Sheet Material in a Progressive Die 14th

Tailoring the Hardness in Multi-stage Press Hardening of 22M...

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14th International Conference on technology of Plasticity, ICTP 2023

作者： Martschin, Juri Wrobel, Malte Grodotzki, Joshua Tekkaya, A. Erman Institute of Forming Technology and Lightweight Components TU Dortmund University Dortmund Germany Institute of Mechanical Process Engineering and Mechanics Karlsruhe Institute of Technology Karlsruhe Germany

ISBN: (纸本)9783031409196

Multi-stage press hardening enables a stepwise control of the thermo-mechanical history during press hardening, thereby facilitating a flexible hardness tailoring. Further degrees of freedom arise from utilizing rapid austenitization by induction heating within the first process stage. To assess the potential of rapid austenitization and a subsequent multi-stage thermo-mechanical history for tailoring the hardness, near-process characterizations are carried out with 22MnB5 steel. By a variation of the austenitizing temperature and dwell time, when cooling at a rate of 30 K/s, a hardness between 310 and 448 HV was set. By inducing a strain of 0.1 after rapid austenitization, the hardness was reduced by 15% due to an accelerated ferrite and bainite transformation. However, it was observed that a second, subsequent induced strain can potentially increase the hardness by work hardening. Using the example of multi-stage press hardening with rapid austenitization implemented in a progressive die, the hardness of 22MnB5 sheet material is tailored. A hardness between 350 and 445 HV was set by varying the austenitization parameters and the strain induced with a controllable blank holder. © 2024, The Author(s), under exclusive license to Springer Nature Switzerland AG.

关键词： Hardness

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Innovative Autothermal Reactor Design via Additive Manufacturing: Optimization of Catalytic Exothermic Reactions Using Porous Media for Heat Management

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Procedia CIRP 2024年 128卷 411-417页

作者： Masoud Mahmoudizadeh Christoph Klahn Roland Dittmeyer Karlsruhe Institute of Technology (KIT) Institute for Micro Process Engineering (IMVT) 76344 Eggenstein-Leopoldshafen Germany Karlsruhe Institute of Technology (KIT) Institute of Mechanical Process Engineering and Mechanics (MVM) 76131 Karlsruhe Germany

Designing autothermal reactors demands meticulous heat management throughout their structure. In cases where reaction heat is sourced from catalytic exothermic reactions, the distribution of this heat becomes critical. This paper explores the utilization of additive manufacturing techniques to fabricate reactors in a single, seamless process. This innovative approach allows for the precise mixing of fuel and oxidant, facilitating reactions in accordance with predefined patterns. Specifically, the study investigates the incorporation of a porous medium, acting as a diffusive medium for the oxidant (e.g. air). The reaction heat is generated at the catalyst sites when the fuel (e.g. methane) reacts with the oxidant. To benchmark this innovative design, a laser-cut distributor with air holes in series is used as a point of comparison. Employing additive manufacturing techniques, these reactors are crafted from high-temperature stainless steel Crofer 22 APU using laser-based powder bed fusion (PBF-LB/M). The solid and porous components are produced with parameters individually optimized for each part. Notably, flow uniformity, temperature profile along the reactor and concentration distribution of oxygen, derived from simulation outcomes, emerge as pivotal factors in effectively coupling exothermic and endothermic reactions within the system. It leads printing flexible and complex designs in only one step.

关键词： Reactor Design Additive Manufacturing Autothermal Reactor Gas Distribution Design Heat Management Porous Medium

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Feedforward control of flat hybrid automata: a behavioral systems theory approach 63

Feedforward control of flat hybrid automata: a behavioral sy...

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63rd IEEE Conference on Decision and Control, CDC 2024

作者： Zahn, Frederik Kleinert, Tobias Hagenmeyer, Veit Karlsruhe Institute of Technology Institute for Automation and Applied Informatics Karlsruhe Germany Rwth Aachen University Chair of Process Control Engineering Aachen Germany

ISBN: (纸本)9798350316339

Differential flatness has been defined in the literature for continuous time dynamical systems and for discrete time systems. We define flatness of automata from the perspective of behavioral systems theory, and synthesize a flatness definition for hybrid automata. These new definitions allow for feedforward trajectory generation for flat hybrid automata. Additionally, we provide necessary and sufficient conditions of hybrid automaton flatness for different types of continuous state constraints and switching conditions, and how to compute whether a hybrid automaton is flat. We illustrate feedforward trajectory generation based on our findings for a robotic manipulator example. © 2024 IEEE.

关键词： Continuous time systems

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Design and manufacturing of integrated fluidic channels in glass parts by vat-photopolymerization additive manufacturing

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Procedia CIRP 2024年 128卷 917-922页

作者： Sijia Liu Christoph Klahn Karlsruhe Institute of Technology IMVT Institute for Micro Process Engineering Hermann-von-Helmholz-Platz 1 76344 Eggenstein-Leopoldshafen Germany Karlsruhe Institute of Technology MVM Institute of Mechanical Process Engineering and Mechanics Geb. 30.70 76131 Karlsruhe Germany

Accurate manufacturing of integrated small-scale fluidic channels in glass structure is of great importance for chemical flow reactors. Vat-photopolymerization of fused silica glass is one of the most promising additive manufacturing technologies to fabricate such structures. It enables the fabrication of glass in a layer-by-layer manner, employing photocurable resin with glass particle fillers, followed by a subsequent thermal treatment to create transparent, fully dense parts. Due to the presence of solid particles, the dimensional accuracy of parts produced by this process is reduced by light scattering. This particularly affects the feasibility and accuracy of small channels, which limits their application as integrated fluidic channel in flow reactors although fused silica glass has excellent chemical and thermal stability. Appropriate printing conditions and rational design play a vital role in ensuring the accuracy of fluidic channels. In accordance with the principle of progressive complexity, this article presents a method to design and manufacture integrated small-scale fluidic channels in glass structures. The case study representing a complex fluidic channel demonstrates the implementation of manufacture and design parameters in a typical flow reactor unit. This work has great implications for designing integrated fluidic channels using particle filler-based vat-photopolymerization additive manufacturing process.

关键词： Design Challenges & Innovations Design for Additive Manufacturing Particle Filler-based Vat-Photopolymerization micro process engineering

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Accelerated design of Power-to-X process chains for transient operation using Recurrent Neural Networks

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Procedia CIRP 2024年 128卷 668-673页

作者： Philipp Rentschler Stefanie Baranowski Christoph Klahn Roland Dittmeyer Karlsruhe Institute of Technology Institute for Micro Process Engineering (IMVT) Hermann-von-Helmholtz-Platz 1 76344 Eggenstein-Leopoldshafen Germany Karlsruhe Institute of Technology Institute of Mechanical Process Engineering and Mechanics (MVM) Kaiserstraße 12 76131 Karlsruhe Germany

Climate change requires a reorientation towards renewable energy generation and storage technologies, especially from solar and wind-based sources. Power-to-X technologies offer a promising way to convert renewable energy into chemical energy carriers based on green hydrogen. A major obstacle to the implementation of such systems is the need to operate the plants dynamically to account for fluctuations. The conventional design of these process chains is usually done through complex dynamic flowsheet simulations, which require specialized engineers and are therefore time-consuming and costly. This study presents an innovative approach to build surrogate models of process chains by using Recurrent Neural Networks and in detail Long Short-Term Memory. To establish a basis for the training data of these models, process simulations were performed with respect to critical parameters for plant dynamics and capacity adjustment. The developed models can represent the dynamics of the process and allow the estimation of annual production volumes for different geographical locations, based on local wind speeds. In addition, plant-specific variables, such as the number of cells in hydrogen-producing electrolysis, can be modified and optimized. These models open the possibility of making informed decisions at an early project stage and reduce the risk of implementing dynamic Power-to-X plants.

关键词： Design methodology tools technologies Design of X

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Design for Additive Manufacturing Education of process engineering Students on an Industrial Challenge

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Procedia CIRP 2024年 128卷 911-916页

作者： Mertcan Kaya Christoph Klahn Karlsruhe Institute of Technology IMVT Institute for Micro Process Engineering Hermann-von-Helmholtz-Platz 1 76344 Eggenstein-Leopoldshafen Germany Karlsruhe Institute of Technology MVM Institute of Mechanical Process Engineering and Mechanics Geb. 30.70 76131 Karlsruhe Germany

As the use of additive manufacturing (AM) is increasing in many sectors, the need of design education for AM has gained importance. Solving the challenges of an application with the advantages of AM requires competencies in selecting a suitable AM process, identifying design opportunities and designing for AM based on an extensive knowledge in the application domain. Hence, it is necessary for all branches engineering to develop AM skills and competencies. This paper describes a lecture and practical to develop AM design competencies in chemical process engineering master students. The course teaches designing complex AM parts based on the need of an application by combining the opportunistic and restrictive aspects AM design with the domain-specific functional requirements. The design education benefits from AM’s advantages in rapid prototyping to provide feedback within the time frame of a course. In order to fulfill the above requirements, an application-oriented design course from requirements to testing, involving a simplified real industrial design problem, has been prepared. Students obtain design requirements at the beginning of the practical and have to develop a device using the advantages of AM. After completing CAD design, the designs of the students are produced with the laser based powder-bed fusion of metal (PBF-LB/M) and bath-based photopolymerisation of polymers, curing using ultraviolet light (VPP-UVL/P) methods. The manufactured designs are tested on the test bench provided by the institute. A case study of a hybrid manufactured reactor with internal condensation supports the conclusion of this paper.

关键词： Type your keywords here separated by semicolons

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Dynamic Modeling and Estimation of Uncharacterized Reactions in H. pluvialis Production Scale Cultivation ⁎

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IFAC-PapersOnLine 2025年第1期59卷 175-180页

作者： Marta Mandis Pascal Jerono Thomas Meurer Karlsruhe Institute of Technology Institute of Mechanical Process Engineering and Mechanics Digital Process Engineering Group Hertzstraße 16 76187 Karlsruhe Germany

This paper addresses the modeling of astaxanthin accumulation in the microal-gae Haematococcus pluvialis, a well-known source of natural astaxanthin, under fluctuating environmental conditions. For biomass growth and astaxanthin accumulation first principles models under sufficient nutrient concentration and high incident light exposure are derived. The obtained models are validated using measurement data of an outdoor production plant, and are the basis for implementing an extended Kalman Filter (EKF) for state and unknown reaction rate estimation.

关键词： Biological systems modeling Identification Parameter state estimation Haematococcus pluvialis Astaxanthin

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Enhancing decanter centrifuge process design with data-driven material parameters in multi-compartment modeling

Journal of Advanced Manufacturing and Processing

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Journal of Advanced Manufacturing and processing 2024年第3期6卷

作者： Zhai, Ouwen Ehret, Niklas Rhein, Frank Gleiss, Marco Institute of Mechanical Process Engineering and Mechanics Karlsruhe Institute of Technology Karlsruhe Germany

Predicting the separation performance of decanter centrifuges is challenging due to dynamic events within the apparatus. Current methods for designing decanter centrifuges rely on simplified models, often leading to inaccuracies. Consequently, manufacturers must perform time-intensive pilot scale experiments to derive their own correction factors. Growing computing power sparks interest in alternative modeling strategies. Grey box models (GBM) combine mechanistic white box models (WBM) and data-driven black box models (BBM), with the optimal structure (parallel or serial) varying by application. For modeling decanter centrifuges, we propose a serial GBM that comprises an artificial neural network that outputs unknown material parameters into a first-principle multi-compartment model. Comparing this approach to alternative data-driven modeling strategies (pure BBM, parallel GBM), we conclude that the serial GBM excels in terms of extrapolation, prediction ability, and transparency while also enabling a better comprehension of the separation process. © 2024 The Author(s). Journal of Advanced Manufacturing and processing published by Wiley Periodicals LLC on behalf of American institute of Chemical Engineers.

关键词： Machine learning

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Exploiting Asymmetries in Diffusively Coupled Oscillators to Enable Frequency Tunability in Neuromorphic Devices 1

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IFAC-PapersOnLine 2025年第1期59卷 217-222页

作者： Hermann Folke Johann Rolf Thomas Meurer Digital Process Engineering Group Institute of Mechanical Process Engineering and Mechanics Karlsruhe Institute of Technology Hertzstr. 16 D-76187 Karlsruhe Germany

By exploiting controllable asymmetries, consensus in networks can be adjusted. In case of coupled oscillators, the characteristic frequencies of the network can be controlled. This property is called frequency tunability and it is, e.g., induced by changing the asymmetry between the damping of the oscillators or the coupling between the oscillators. Subsequently, the frequency tunability of two diffusively coupled Andronov-Hopf oscillators is investigated by analyzing the emergence of Andronov-Hopf bifurcations. This is done by investigating the local dynamics of the corresponding system. It turns out that the number of critical points of the Andronov-Hopf bifurcation is determined by analyzing a polynomial whose degree changes based on the choice of the bifurcation parameter. Thus, this polynomial is analyzed in terms of two different bifurcation parameters: (i) symmetric damping and (ii) symmetric coupling. In case of (i), the system has two critical points, which correspond to Andronov-Hopf bifurcations. In contrast to this, for (ii) the number of critical points varies between one and three depending on the asymmetric damping.

关键词： Andronov-Hopf oscillators Bifurcation analysis Andronov-Hopf bifurcation Frequency Tunability Bio-inspired acoustic sensing Neuromorphic engineering

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