%0 Journal Article %J Energy Conversion and Management %D 2017 %T Dynamic equation-based thermo-hydraulic pipe model for district heating and cooling systems %A Brahm van der Heijde %A Marcus Fuchs %A Carles Ribas Tugores %A Gerald Schweiger %A Kevin Sartor %A Daniele Basciotti %A Dirk Muller %A Christoph Nytsch-Geusen %A Michael Wetter %A Lieve Helsen %X

Simulation and optimisation of district heating and cooling networks requires efficient and realistic models of the individual network elements in order to correctly represent heat losses or gains, temperature propagation and pressure drops. Due to more recent thermal networks incorporating meshing decentralised heat and cold sources, the system often has to deal with variable temperatures and mass flow rates, with flow reversal occurring more frequently. This paper presents the mathematical derivation and software implementation in Modelica of a thermo-hydraulic model for thermal networks that meets the above requirements and compares it to both experimental data and a commonly used model. Good correspondence between experimental data from a controlled test set-up and simulations using the presented model was found. Compared to measurement data from a real district heating network, the simulation results led to a larger error than in the controlled test set-up, but the general trend is still approximated closely and the model yields results similar to a pipe model from the Modelica Standard Library. However, the presented model simulates 1.7 (for low number of volumes) to 68 (for highly discretized pipes) times faster than a conventional model for a realistic test case. A working implementation of the presented model is made openly available within the IBPSA Modelica Library. The model is robust in the sense that grid size and time step do not need to be adapted to the flow rate, as is the case in finite volume models.

%B Energy Conversion and Management %V 151 %G eng %2 2001049 %R 10.1016/j.enconman.2017.08.072 %0 Journal Article %J Bauphysik %D 2009 %T Neue objektorientierte hygrothermische Modell-Bibliothek zur Ermittlung des hygrothermischen und hygienischen Komforts in Räumen %A Thierry Stephane Nouidui %A Klaus Sedlbauer %A Christoph Nytsch-Geusen %A Kurt Kießl %B Bauphysik %V 31 %P 271-278 %G eng %R 10.1002/bapi.200910036 %0 Conference Proceedings %B BAUSIM 2008 %D 2008 %T Gebäudesimulation mit adaptiven Modellierungsansätzen %A Christoph Nytsch-Geusen %A Thierry Stephane Nouidui %B BAUSIM 2008 %C Kassel, Germany %G eng %0 Conference Proceedings %B 8th Nordic Symposium on Building Physics in the Nordic Countries 2008 %D 2008 %T Object-oriented hygrothermal building physics library as a tool to predict and to ensure a thermal and hygric indoor comfort in building construction by using a Predicted-Mean-Vote (PMV) control ventilation system %A Thierry Stephane Nouidui %A Christoph Nytsch-Geusen %A Andreas Holm %A Klaus Sedlbauer %X

The indoor temperature and humidity conditions of the building envelope are important parameters for the evaluation of the thermal and hygric indoor comfort. In the research project GENSIM a new hygrothermal building library, based on the object- and equation-oriented model description language Modelica® has been developed by the Fraunhofer Institutes IBP and FIRST. This library includes many models as for instance a hygrothermal wall model, an air volume model, a zone model, a window model and an environment model. Due to the object-oriented modelling approach, some models of this library can be configured to a complex hygrothermal room model, which can predict the time dependent indoor temperature and humidity conditions in a building construction. In this paper we will introduce in a first step the object-oriented hygrothermal room model of this library. In a second step, the validation of the room model with some field experiments will be shown. In a third step we willpresent some simulation results, we obtained by coupling the room model with an implemented Predicted-Mean-Vote (PMV) control ventilation system to predict and to ensure a thermal and hygric indoor comfort in one case study. In the conclusion, the possible range of future applications of this new hygrothermal building physics library and demands for further research are indicated.

%B 8th Nordic Symposium on Building Physics in the Nordic Countries 2008 %C Copenhagen, Denmark %V 2 %P pp.825-832 %G eng %0 Conference Proceedings %B 5th International Modelica Conference %D 2006 %T Advanced modeling and simulation techniques in MOSILAB: A system development case study %A Christoph Nytsch-Geusen %A Thilo Ernst %A Peter Schwarz %A Mathias Vetter %A Andreas Holm %A Juergen Leopold %A Alexander Mattes %A Andre Nordwig %A Peter Schneider %A Christoph Wittwer %A Thierry Stephane Nouidui %A Gerhardt Schmidt %B 5th International Modelica Conference %S 2006 %P pp.63-72 %G eng %0 Conference Paper %B 16. Symposium Thermische Solarenergie %D 2006 %T MOSILAB: Ein Modelica-Simulationswerkzeug zur energetischen Gebäude- und Anlagensimulation %A Christoph Nytsch-Geusen %A Andre Nordwig %A Mathias Vetter %A Christoph Wittwer %A Thierry Stephane Nouidui %A Peter Schneider %B 16. Symposium Thermische Solarenergie %C Bad Staffelstein, Germany %@ 3-934681-45-X %G eng %0 Conference Proceedings %B BauSIM 2006 %D 2006 %T Validierung der eindimensionalen hygrothermischen Wandmodelle der Modelica-Bibliothek "BuildingPhysicsLibrary" %A Thierry Stephane Nouidui %A Christoph Nytsch-Geusen %A Andreas Holm %B BauSIM 2006 %C Munich, Germany %P pp.144-146 %@ 978-3-00-019823-6 %G eng %0 Conference Paper %B Ninth International IBPSA Conference %D 2005 %T A hygrothermal building model based on the object-oriented modeling language Modelica %A Christoph Nytsch-Geusen %A Thierry Stephane Nouidui %A Andreas Holm %A Wolfram Haupt %B Ninth International IBPSA Conference %C Montreal, Canada %8 2005 %@ 2-553-01152-0 %G eng %0 Conference Proceedings %B 4th International Modelica Conference %D 2005 %T MOSILAB: Development of a modelica based generic simulation tool supporting modal structural dynamics %A Christoph Nytsch-Geusen %A Thilo Ernst %A Peter Schneider %A Mathias Vetter %A Andreas Holm %A Juergen Leopold %A Ullrich Doll %A Andre Nordwig %A Peter Schwarz %A Christoph Wittwer %A Thierry Stephane Nouidui %A Gerhardt Schmidt %A Alexander Mattes %B 4th International Modelica Conference %C Hamburg, Germany %P pp.527-534 %G eng