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4th International Conference on Advances in Solidification processes, ICASP 2014

作者： Ahmadein, M. Wu, M. Sturz, L. Zimmermann, G. Ludwig, A. Drpartment for Modeling and Simulation of Metallurgical Processes University of Leoben Austria Department of Production Engineering and Mechanical Tanta University Egypt Christian-Doppler Laboratory for Advanced Process Simulation of Solidification and Melting University of Leoben Austria ACCESS E.V. Aachen Germany

A solidification experiment "TRACE" of the transparent alloy Neopentylglycol (NPG)-37.5wt.% D-Camphor (DC) was conducted on-board the sounding rocket TEXUS-47 in low-gravity environment to investigate the columnar growth and the columnar-to-equiaxed transition (CET). To improve the fundamental understanding of solidification and CET in microgravity, the current laboratory scale experiment was tried to be numerically reproduced by a recently developed 5-phase volume averaging model. The temperature gradient in the solidification cell is applied to the simulation. In absence of melt flow, the calculated cooling curves, columnar tip position, tip undercooling and velocity, and number density of equiaxed crystals were compared to the results of in-situ real-time observations of the experiment. The CET could be predicted at position close to that of experiment. simulation reveals the competitive growth between the columnar and equiaxed crystals before CET. Modelling parameters of equiaxed nucleation and columnar tip growth are the key to regulate this competition and to locate the CET. Experimental verification of modelling parameters considering melt flow is intended in the future work.

关键词： Microgravity

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Modelling Al-4wt.%Cu as-cast structure using equiaxed morphological parameters deduced from in-situ synchrotron X-ray radiography 4

Modelling Al-4wt.%Cu as-cast structure using equiaxed morpho...

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4th International Conference on Advances in Solidification processes, ICASP 2014

作者： Ahmadein, M. Wu, M. Reinhart, G. Nguyen-Thi, H. Ludwig, A. Department of Modeling and Simulation of Metallurgical Processes University of Leoben Austria Department of Production Engineering and Mech. Design Tanta University Egypt Christian-Doppler Laboratory for Advanced Process Simulation of Solidification and Melting University of Leoben Austria Aix- Marseille University France CNRS IM2NP UMR 7334 Campus Saint-Jérôme Case 142 Marseille Cedex 2013397 France

The as-cast structure of laboratory scale Al-4wt.%Cu was numerically calculated using assumed morphological parameters. Two parameters are identified: The shape factor which correlates the growth velocity of dendrite envelope to that of the tip;and the sphericity of the equiaxed envelope or the circularity of the columnar trunk envelope which is required to calculate the averaged species diffusion flux across the envelope. In the present work, the real-time radiographs of equiaxed solidification experiment carried out on Al-4wt.%Cu at the European Synchrotron Radiation Facility are used to track the development of crystal envelope with time. The growth rate of the equivalent circular envelope was correlated to dendrite tip growth velocity to deduce the shape factor. The sphericity of dendrite envelope is estimated over the time. The average of the deduced morphological parameters is applied to the model to predict the as-cast structure. The results were compared to those obtained by using morphological parameters from literature. The predicted phase quantities, columnar-to- equiaxed transition, and macrosegregation exhibited significant dependence on those parameters. The predicted macrosegregation using the experimentally deduced parameters fits better to the measurements.

关键词： X ray radiography

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Correction to: Use of Physiologically Based Pharmacokinetic (PBPK) modeling for Predicting Drug-Food Interactions: an Industry Perspective

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The AAPS journal 2020年第1期23卷 6页

作者： Arian Emami Riedmaier Kevin DeMent James Huckle Phil Bransford Cordula Stillhart Richard Lloyd Ravindra Alluri Sumit Basu Yuan Chen Varsha Dhamankar Stephanie Dodd Priyanka Kulkarni Andrés Olivares-Morales Chi-Chi Peng Xavier Pepin Xiaojun Ren Thuy Tran Christophe Tistaert Tycho Heimbach Filippos Kesisoglou Christian Wagner Neil Parrott DMPK and Translational Modeling AbbVie Inc. North Chicago Illinois USA. arian.emamiriedmaier@***. Global DMPK Takeda Pharmaceutical Co. Ltd. San Diego California USA. Drug Product Technology Amgen Thousand Oaks California USA. Modeling & Informatics Vertex Pharmaceuticals Boston Massachusetts USA. Pharmaceutical R&D Formulation & Process Sciences F.Hoffmann-La Roche Ltd. Basel Switzerland. Computational & Modelling Sciences Platform Technology Sci-ences GlaxoSmithKline R&D Ware Hertfordshire UK. Clinical Pharmacology and Safety Sciences R&D AstraZeneca Cambridge UK. Pharmacokinetic Pharmacodynamic and Drug Metabolism-Quantitative Pharmacology and Pharmacometrics (PPDM-QP2)Merck & Co Inc. West Point Pennsylvania USA. Department of Drug Metabolism and Pharmacokinetics Genentech South San Francisco California USA. Formulation Development Vertex Pharmaceuticals Boston Massachusetts USA. Formulation Development Cyclerion Therapeu-tics Inc. Cambridge Massachusetts USA. Chemical & Pharmaceutical Profiling Novartis Institutes for Biomedical Research Cambridge Massachusetts USA. Department of Pharmacokinetics and Drug Metabolism AmgenInc Cambridge Massachusetts USA. Pharmaceutical Sciences Roche Pharmaceutical Research andEarly Development Roche Innovation Center Basel Switzerland. Drug Metabolism and Pharmacokinetics Theravance Biopharma South San Francisco California USA. New Modalities and Parenteral Development PharmaceuticalTechnology & Development Operations AstraZeneca Maccles-field UK. Modeling & Simulation PK Sciences Novartis Institutes of Biomedical Research East Hanover New Jersey USA. Computational & Modelling Sciences Platform Technology Sci-ences GlaxoSmithKline R&D Collegeville Pennsylvania USA. Pharmaceutical Sciences Janssen Research & Development Beerse Belgium. PBPK & Biopharmaceutics Novartis Institutes of Biomedical Research Wayne New Jersey USA. Pharmaceutical Sciences Merck & Co. Inc. Kenilworth New Jersey US

An Erratum to this paper has been published: https://***/10.1208/s12248-020-00535-z.

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The development of China's Yangtze River Economic Belt:how to make it in a green way?

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Science Bulletin 2017年第9期62卷 648-651页

作者： Yushun Chen Shuanghu Zhang Desheng Huang Bai-Lian Li Junguo Liu Wenjin Liu Jing Ma Fang Wang Yong Wang Shengjun Wu Yegang Wu Jinyue Yan Chuanbo Guo Wei Xin Hao Wang Institute of Hydrobiology & State Key Laboratory of Freshwater Ecology and Biotechnology Chinese Academy of Sciences Wuhan 430072 China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research Beijing 100038 China Policy Research Center for Environment and Economy Ministry of Environmental Protection of P.R. China Beijing 100029 China Ecological Complexity and Modeling Laboratory University of California Riverside CA 92521-0124 USA School of Environmental Science and Engineering Southern University of Science and Technology of China Shenzhen 518055 China Orient Landscape Industry Group Ltd. Beijing 100015 China Department of Biological and Environmental Sciences Alabama A&M University Normal AL 35762 USA Key Laboratory of Reservoir Aquatic Environment & Research Center for Ecological Process of Three Gorges' Eco-Environment Chongqing Institute of Green and Intelligent Technology Chinese Academy of Sciences Chongqing 400714 China Institute of Eco-city Planning and Design Shanghai BoDa Development Corporation Shanghai 200333 China KTH-Royal Institute of Technology SE-10044 Stockholm Sweden & Malardalen University SE-72123 Vasteras Sweden

The Yangtze River is one of the largest and longest rivers in *** river originates in the Tibet-Qinghai Plateau(headwater reach),passes through the mountainous provinces of Sichuan,Yunnan and Chongqing(upper reach),flows into the Central Plain(middle reach)and Lower Plain(lower reach),and finally empties into the East China Sea in Shanghai(estuary).The Yangtze River Economic Belt(YREB;Fig.1)has a surface area of 2.1

关键词： In The development of China’s Yangtze River Economic Belt:how to make it in a green way

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Numerical investigation of solidification and CET of the transparent alloy NPG-37.5 wt.% DC in microgravity 'TRACE' experiment

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IOP Conference Series: Materials Science and Engineering 2016年第1期117卷

作者： M Ahmadein M Wu L Sturz G Zimmermann A Ludwig Chair for Modeling and Simulation of Metallurgical Processes University of Leoben Austria Department of Production Engineering and Mechanical Tanta University Egypt Christian-Doppler Laboratory for Advanced Process Simulation of Solidification & Melting University of Leoben Austria ACCESS e.V. Aachen Germany

A solidification experiment 'TRACE' of the transparent alloy Neopentylglycol (NPG)-37.5wt.% D-Camphor (DC) was conducted on-board the sounding rocket TEXUS-47 in low-gravity environment to investigate the columnar growth and the columnar-to-equiaxed transition (CET). To improve the fundamental understanding of solidification and CET in microgravity, the current laboratory scale experiment was tried to be numerically reproduced by a recently developed 5-phase volume averaging model. The temperature gradient in the solidification cell is applied to the simulation. In absence of melt flow, the calculated cooling curves, columnar tip position, tip undercooling and velocity, and number density of equiaxed crystals were compared to the results of in-situ real-time observations of the experiment. The CET could be predicted at position close to that of experiment. simulation reveals the competitive growth between the columnar and equiaxed crystals before CET. Modelling parameters of equiaxed nucleation and columnar tip growth are the key to regulate this competition and to locate the CET. Experimental verification of modelling parameters considering melt flow is intended in the future work.

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Modelling Al-4wt.%Cu as-cast structure using equiaxed morphological parameters deduced from in-situ synchrotron X-ray radiography

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IOP Conference Series: Materials Science and Engineering 2016年第1期117卷

作者： M Ahmadein M Wu G Reinhart H Nguyen-Thi A Ludwig Chair for Modeling and Simulation of Metallurgical Processes University of Leoben Austria Department of Production Engineering and Mech. Design Tanta University Egypt Christian-Doppler Laboratory for Advanced Process Simulation of Solidification & Melting University of Leoben Austria Aix- Marseille University CNRS IM2NP UMR 7334 Campus Saint-Jérôme Case 142 13397 Marseille Cedex 20 France

The as-cast structure of laboratory scale Al-4wt.%Cu was numerically calculated using assumed morphological parameters. Two parameters are identified: The shape factor which correlates the growth velocity of dendrite envelope to that of the tip; and the sphericity of the equiaxed envelope or the circularity of the columnar trunk envelope which is required to calculate the averaged species diffusion flux across the envelope. In the present work, the real-time radiographs of equiaxed solidification experiment carried out on Al-4wt.%Cu at the European Synchrotron Radiation Facility are used to track the development of crystal envelope with time. The growth rate of the equivalent circular envelope was correlated to dendrite tip growth velocity to deduce the shape factor. The sphericity of dendrite envelope is estimated over the time. The average of the deduced morphological parameters is applied to the model to predict the as-cast structure. The results were compared to those obtained by using morphological parameters from literature. The predicted phase quantities, columnar-to- equiaxed transition, and macrosegregation exhibited significant dependence on those parameters. The predicted macrosegregation using the experimentally deduced parameters fits better to the measurements.

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Assessment of Model-Plant Mismatch by the Nominal Sensitivity Function for Unconstrained MPC

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IFAC-PapersOnLine 2015年第8期48卷 753-758页

作者： Viviane Rodrigues Botelho Jorge Otávio Trierweiler Marcelo Farenzena Ricardo Duraiski GIMSCOP - Group of Intensification Modeling Simulation Control and Optimization of Process Federal University of Rio Grande do Sul Chemical Engineering Department R. Eng. Luis Englert s/n. Campus Central. CEP: 90040-040 - Porto Alegre - RS - BRAZIL Trisolutions Engineering Solutions LTD A. R. General Bento Martins 24. CEP: 90010-080 - Porto Alegre - RS - BRAZIL

Model Predictive Control (MPC) is a class of control systems which use a dynamic process model to predict the best future control actions based on past information. Thus, a representative process model is a key factor for its correct performance. Therefore, the investigation of model-plant-mismatch effect is very important issue for MPC performance assessment, monitoring, and diagnosis. This paper presents a method for model quality evaluation based on the investigation of closed-loop data and the nominal complementary sensitivity function. The proposed approach ensures that the MPC tuning is taken into account in the evaluation of the model quality. A SISO case study is analyzed and the results show the effectiveness of the method.

关键词： Model Predictive Control Model Plant Mismatch Sensitivity Function Control Performance Assessment

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A numerical study of the influence of pouring technique on the as-cast structure of al-cu ingots

A numerical study of the influence of pouring technique on t...

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6th International Conference on Solidification and Gravity

作者： Ahmadein, M. Wu, M.H. Schumacher, P. Ludwig, A. Chair for Modeling and Simulation of Metallurgical Processes University of Leoben Austria Department of Production Engineering and Mechanical Tanta University Egypt Christian-Doppler Laboratory for Advanced Process Simulation of Solidification and Melting University of Leoben Austria Chair for Casting Research University of Leoben Austria

ISBN: (纸本)9783038350934

Experimental evidence [Ohno 1987] revealed the influence of some pouring techniques on the as-cast structure. In the current work the process of pouring of the molten Al-4.0 wt.%Cu via one or multiple streams into a graphite mold is studied using a 3-phase model by considering the nucleation, the initial growth and transport of globular equiaxed crystals. The three phases are the melt, air and globular equiaxed crystals. Results showed that pouring via multiple streams increases the volume fraction and number density of crystals in the as-filled state. The subsequent solidification is calculated using a 5-phase mixed columnar-equiaxed solidification model. The five phases are the extradendritic melt, the solid dendrite and interdendritic melt inside the equiaxed grains, the solid dendrite and interdendritic melt inside the columnar grains. As final result the ascast structure including the distinct columnar and equiaxed zones, columnar-to-equiaxed transition (CET), grain size, macrosegregation, and rest eutectic is predicted. Effect of melt convection and crystal sedimentation during the pouring and solidification is taken into account. The predicted ascast structure, under the influence of single/multiple jet pouring, is evaluated by comparison with the available experiments of Ohno. © (2014) Trans Tech Publications, Switzerland.

关键词： Solidification

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Benchmark experiments and numerical modelling of the columnar-equiaxed dendritic growth in the transparent alloy Neopentylglycol-(d)Camphor

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IOP Conference Series: Materials Science and Engineering 2015年第1期84卷

作者： L Sturz M Wu G Zimmermann A Ludwig M Ahmadein ACCESS e.V. Intzestr. 5 52072 Aachen Germany Chair for Modeling and Simulation of Metallurgical Processes University of Leoben Austria Christian-Doppler Laboratory for Advanced Process Simulation of Solidification & Melting University of Leoben Austria Department of Production Engineering and Mech. Design Tanta University Egypt

Solidification benchmark experiments on columnar and equiaxed dendritic growth, as well as the columnar-equiaxed transition have been carried out under diffusion-dominated conditions for heat and mass transfer in a low-gravity environment. The system under investigation is the transparent organic alloy system Neopentylglycol-37.5wt.-%(d)Camphor, processed aboard a TEXUS sounding rocket flight. Solidifications was observed by standard optical methods in addition to measurements of the thermal fields within the sheet like experimental cells of 1 mm thickness. The dendrite tip kinetic, primary dendrite arm spacing, temporal and spatial temperature evolution, columnar tip velocity and the critical parameters at the CET have been analysed. Here we focus on a detailed comparison of the experiment 'TRACE' with a 5-phase volume averaging model to validate the numerical model and to give insight into the corresponding physical mechanisms and parameters leading to CET. The results are discussed in terms of sensitivity versus numerical parameters.

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Spline dynamic matrix: A novel representation of dynamic models

Spline dynamic matrix: A novel representation of dynamic mod...

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8th International Symposium on Advanced Control of Chemical processes, ADCHEM 2012

作者： Escobar, Matheus S. Trierweiler, Jorge O. Department of Chemical Engineering GIMSCOP - Group of Intensification Modeling Simulation Control and Optimization of Process Federal University of Rio Grande do Sul Porto Alegre CO 90040-040 Brazil

ISBN: (纸本)9783902823052

In the field of dynamic simulation, Finite Impulse Response (FIR), Step Response (SR) and discrete state-space (DSS) approaches are the most widespread model representations developed so far. Such representations, however, have some disadvantages, regarding simulation speed, computational load and fixed sampling. To cope with these restrictions, this work introduces a new model representation called Spline Dynamic Matrix (SDM), which combines the dynamic matrix model with the inputs parameterized by piecewise cubic splines. Such representation results in reduced matrixes, allowing variable spacing over simulation horizon. When compared with DSS representation, SDM behaves remarkably well, with mild deviations inherent to spline interpolation, keeping model adherence. SDM also presents itself as an effective way to implement model predictive controllers (MPC), being robust when compared to traditional formulation. © 2012 IFAC.

关键词： Impulse response

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