Conference article

Integrated Process and Molecular Design with Modelica Using Continuous-Molecular Targeting

Christoph Udo Gertig
Institute of Technical Thermodynamics, RWTH Aachen University, Aachen, Germany

Dominik Tillmanns
Institute of Technical Thermodynamics, RWTH Aachen University, Aachen, Germany

Johannes Schilling
Institute of Technical Thermodynamics, RWTH Aachen University, Aachen, Germany

Uwe Bau
Institute of Technical Thermodynamics, RWTH Aachen University, Aachen, Germany

Franz Lanzerath
Institute of Technical Thermodynamics, RWTH Aachen University, Aachen, Germany

Joachim Gross
Institute of Technical Thermodynamics and Thermal Process Engineering, Stuttgart University, Stuttgart, Germany

André Bardow
Institute of Technical Thermodynamics, RWTH Aachen University, Aachen, Germany

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Published in: Proceedings of the 12th International Modelica Conference, Prague, Czech Republic, May 15-17, 2017

Linköping Electronic Conference Proceedings 132:10, p. 101-110

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Published: 2017-07-04

ISBN: 978-91-7685-575-1

ISSN: 1650-3686 (print), 1650-3740 (online)


The performance of many chemical and energy con-version processes depends on the choice of the mole-cules used, e.g. as solvents or working fluids. To cap-ture the complex relations between the properties of the molecules used and the process conditions, the selection of suitable molecules should be directly integrated into process design. Solving the resulting challenging integrated design problem is enabled by the Continous-Molecular Targeting – Computer-Aided Molecular Design (CoMT-CAMD) approach. Here, the combinatorial complexity of the molecular decisions is avoided by relaxing molecular parameters in a physically-based thermodynamic model. So far, implementations of CoMT-CAMD were based on procedural programming languages. This impedes reusability and the investigation of process variants as well as the design of complex processes. In order to overcome these shortcomings, we implement the CoMT-CAMD approach based on object-oriented process modeling and thus enable the integrated process and molecular design with Modelica. The resulting approach is demonstrated for the design of a process and the working fluid for a geothermal Organic Rankine Cycle application.


GenOpt, optimization, integrated fluid and process design, computer-aided molecular design, PCSAFT


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