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120. Personal Climatization Systems—A Review on Existing and Upcoming Concepts.

Author

Warthmann, Alexander, Wölki, Daniel, Metzmacher, Henning, and van Treeck, Christoph

Subjects
THERMAL comfort, INDOOR air quality, SKIN temperature
Abstract

To accomplish the current climate goals of the federal republic of Germany, energy efficiency within the building and automotive sector must improve considerably. One possible way to reduce the high amount of energy required for heating, ventilation, and air-conditioning (HVAC) is the introduction of personal climatization systems in combination with the extension of the standardized room air temperature range. Personal systems allow improvements of climatic conditions (heating, cooling, and air quality) within sub-areas of the room instead of conditioning an entire room air volume. In this regard, personal systems are perfectly suitable for locations with local air-conditioning focal points, such as open-plan offices and vehicle cabins, where they substantially improve the energy efficiency of the entire system. This work aims to summarize previously conducted research in the area of personal climatization systems. The investigated local thermal actuators comprise fans for the generation of air movement, ventilators for the improvement of the air quality within the respiratory area of persons, water-conditioned panels for the climatization of persons via longwave radiation and conduction, radiant heaters, and combinations of the systems. Personal systems are superior to mixing ventilation regarding the improvement of the perceived air quality and thermal comfort. Furthermore, the introduced overview shows that personal climatization systems are generally more energy-efficient than conventional air-conditioning and facilitates the extension of the indoor air temperature corridor of the HVAC. Table fans and climatized seats are highly effective in connection with the improvement of personal thermal comfort. The performance of the overwhelming majority of applied personal environmental control systems is user-controlled or depends on a predefined load profile, which is generally defined person independent. Single studies reveal that effectively controlled automated systems have a similar thermal impact on a user's thermal comfort as user-controlled ones. The implementation of an automated control system is feasible by using novel approaches such as the so-called human-centered closed loop control-platform (HCCLC-platform). The latter contains a central data server which allows asynchronous, bi-directional communication between multi-modal sensor data, user feedback systems, thermal actuators and numerical calculation models used to assess the individual thermal comfort of a person. This enables a continuous and holistic reflection of the thermal situation inside a room and the estimation of the corresponding impact on an individual's thermal comfort. Considering the measured and simulated thermal state of a single person, the described system is capable of determining body-part-specific energy requirements that are needed to keep the overall thermal comfort level of an individual person on a high level. [ABSTRACT FROM AUTHOR]

Published
2019
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126. Too hot to carry on? Disinclination to persist at a task in a warm office environment.

Author

Syndicus, Marc, Wiese, Bettina S., and van Treeck, Christoph

Subjects
WORK environment & psychology, STUDENTS, TEMPERATURE, WORK capacity evaluation, TASK performance
Abstract

We investigated the effect of an elevated ambient temperature on performance in a persistence task. The task involved the coding of incorrect symbols and participants were free to decide how long to spend performing this task. Applying a between-subject design, we tested 125 students in an office-like environment in one of the three temperature conditions. The comfort condition (Predicted Mean Vote [PMV] = 0.01) featured an average air temperature of 24 °C. The elevated ambient temperature condition was 28 °C (PMV = 1.17). Condition three employed an airstream of approximately 0.8 m/s, intended to compensate for performance decrements at the elevated air temperature (28 °C, PMV = 0.13), according to Fanger’s thermal comfort equation. Participants in the warm condition were significantly less persistent compared with participants in the control and compensation conditions. As predicted by the thermal comfort equation, the airstream seemed to compensate for the higher temperature. Participants’ persistence in the compensation and comfort conditions did not differ. Practitioner Summary:A laboratory experiment involving a simulated office environment and three ambient temperature conditions (24 °C, 28 °C and 28 °C plus airstream) showed that persistence at a task is significantly impaired at 28 °C. An airstream of 0.8 m/s at 28 °C compensated for the disinclination to persist with the task. [ABSTRACT FROM PUBLISHER]

Published
2018
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127. In the Heat and Noise of the Moment: Effects on Risky Decision Making.

Author

Syndicus, Marc, Wiese, Bettina S., and van Treeck, Christoph

Subjects
DECISION making, COGNITIVE ability, CRITICAL thinking, WORK environment, JOB stress
Abstract

Two studies, comprising 128 participants, were conducted to examine possible detrimental effects of noise and moderate heat stress on decision making. Three tasks involving risky decisions were used: a lottery choice task, the Balloon Analogue Risk Task, and two risk scenario questionnaires. Study 1 (n = 97) involved three noise stressors presented at 60dB(A) and a quiet condition. Compared with all other conditions, a radio podcast about the jubilee of museums caused a significant increase in risk aversion in the Choice Dilemma Questionnaire task. Study 2 (n = 31) compared two groups that completed the aforementioned tasks either in a warm (≥ 30°C) or neutral (≤ 25°C) ambient temperature condition. Participants made significantly riskier decisions in the warm ambient temperature condition in all tasks except the lottery task. Effects were more pronounced among female subjects. Especially elevated ambient temperatures should, therefore, be monitored in office environments to prevent impairments of decision making. [ABSTRACT FROM AUTHOR]

Published
2018
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132. Introduction to building performance modeling and simulation

Author

van Treeck, Christoph Alban, Rank, Ernst, Hauser, Gerd, and Hensen, Jan

Abstract

Habilitationsschrift, Technische Universität München, 2010; 259 Seiten (2010). = Habilitationsschrift, Technische Universität München, 2010, The book on hand provides a basic introduction to the modeling and to the numerical simulation of the energy performance and the thermal quality performance of buildings. It is the conceptual idea to explain the physical background and the numerical techniques which form part of the core of building performance simulation. The knowledge is provided with minimum semantics in terms of creating the particular modules of a geometry-based thermal multizone model step by step. The book addresses students at the graduate or PhD level. At the beginning, a short historical review is given, the different scales and levels in building simulation are explained, and the related simulation community and its communication channels are introduced. Motivated by the European Energy Performance of Buildings Directive, we provide an overview of the energy efficient building design including a few examples for active and passive measures towards sustainable building design. Prior to introducing numerical techniques, a general picture is drawn of the relevant heat balances and energy flow paths in a building. Using a static balancing approach, a calculation example is given for a sample building model. External and internal boundary conditions are summarized, including the weather data acquisition, the pressure and temperature distribution at the building surface, heat transfer coefficients for free and forced convection, as well as the impacts of the urban environment and the climate change to the prediction methods. Detailed material is provided on how to numerically calculate the respective heat and mass flows in a building. This includes heat conduction in solids, internal long wave radiation processes, solar radiation, and optical and thermal properties of windows. Numerical techniques are introduced, such as finite difference methods, numerical integration to calculate view factors, the radiosity method, and a simplified raytracing algorithm. A zone model finally integrates the respective multi physics heat transfer into a single model. Air flows between spaces are treated by a nodal network method. A geometric model thereby forms the basis of the discussed discretization methods. We therefore recapitulate the basic geometrical representation of objects and explain the issue of integration in terms of linking building information modeling and building performance simulation. Validation tests are performed with the developed model in terms of the VDI 6020/6007 benchmark definitions. For the thermal quality performance assessment, information is provided on the human energy balance and thermoregulation, the conditions for thermal comfort, the relevant prediction methods for both steady state uniform and inhomogeneous transient conditions, models to include peoples’ expectation and behavioral adaptation, and the relevant comfort envelopes and calculation methods. Examples clarify the application of the respective models in simulation.

Published
2010
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133. Towards Massive Parallel Fluid Flow Simulations in Computational Engineering

Author

van Treeck, Christoph (Prof. Dr. habil.), Rank, Ernst (Prof. Dr.), Aoki, Takayuki (Prof. Dr.), Frisch, Jérôme, van Treeck, Christoph (Prof. Dr. habil.), Rank, Ernst (Prof. Dr.), Aoki, Takayuki (Prof. Dr.), and Frisch, Jérôme

Abstract

As computer power still grows exponentially, engineering-based problems can be simulated today, which were deemed unsolvable a decade ago. In this work, a simulation pipeline able to work efficiently on massive parallel systems is presented, based on a newly introduced data structure together with an efficient multi-grid-like solver technique. Complex examples and an interactive visualisation are presented in order to demonstrate the capabilities of the chosen approach., Die nach wie vor exponentielle Steigerung der Rechenleistung erlaubt es heute, früher kaum lösbare Probleme aus den Ingenieurwissenschaften zu behandeln. Die hier neu eingeführte Datenstruktur zusammen mit einem mehrgitterähnlichen Gleichungslöser ermöglicht Simulationsläufe, die effizient auf Höchstleitungsrechnern realisiert werden können. Eine interaktive Visualisierung und komplexe Strömungsszenarien unterstreichen die vielfältige Anwendbarkeit des vorgestellten Ansatzes.

Published
2014

134. Towards Massive Parallel Fluid Flow Simulations in Computational Engineering

Author

Rank, Ernst (Prof. Dr.), Rank, Ernst (Prof. Dr.);van Treeck, Christoph (Prof. Dr. habil.);Aoki, Takayuki (Prof. Dr.), Frisch, Jérôme, Rank, Ernst (Prof. Dr.), Rank, Ernst (Prof. Dr.);van Treeck, Christoph (Prof. Dr. habil.);Aoki, Takayuki (Prof. Dr.), and Frisch, Jérôme

Abstract

As computer power still grows exponentially, engineering-based problems can be simulated today, which were deemed unsolvable a decade ago. In this work, a simulation pipeline able to work efficiently on massive parallel systems is presented, based on a newly introduced data structure together with an efficient multi-grid-like solver technique. Complex examples and an interactive visualisation are presented in order to demonstrate the capabilities of the chosen approach., Die nach wie vor exponentielle Steigerung der Rechenleistung erlaubt es heute, früher kaum lösbare Probleme aus den Ingenieurwissenschaften zu behandeln. Die hier neu eingeführte Datenstruktur zusammen mit einem mehrgitterähnlichen Gleichungslöser ermöglicht Simulationsläufe, die effizient auf Höchstleitungsrechnern realisiert werden können. Eine interaktive Visualisierung und komplexe Strömungsszenarien unterstreichen die vielfältige Anwendbarkeit des vorgestellten Ansatzes.

Published
2014

135. FrontMatter.

Author

van Treeck, Christoph, Elixmann, Robert, Rudat, Klaus, Hiller, Sven, Herkel, Sebastian, and Berger, Markus

Published
2016

136. VOM LASERSCAN ZUM PLANUNGSTAUGLICHEN PRODUKTMODELL

Author

Schleinkofer, Matthias, Schäfer, T., van Treeck, Christoph, and Rank, Ernst

Abstract

Im Bereich der Altbausanierung und der Bestandserfassung im Bauwesen ist es häufig notwendig, bestehende Pläne hinsichtlich des Bauwerkszustandes zu aktualisieren oder, wenn diese Pläne nicht (mehr) zugänglich sind, gänzlich neue Planunterlagen des Ist-Zustandes zu erstellen. Ein komfortabler Weg, diese Bauwerksdaten zu erheben, eröffnet die Technologie der Laservermessung. Der vorliegende Artikel stellt in diesem Zusammenhang Ansätze zur Teilautomatisierung der Generierung eines dreidimensionalen Computermodells eines Bauwerkes vor. Als Ergebnis wird ein Volumenmodell bereitgestellt, in dem zunächst die geometrischen und topologischen Informationen über Flächen, Kanten und Punkte im Sinne eines B-rep Modells beschrieben sind. Die Objekte dieses Volumenmodells werden mit Verfahren aus dem Bereich der künstlichen Intelligenz analysiert und in Bauteilklassen systematisch kategorisiert. Die Kenntnis der Bauteilsemantik erlaubt es somit, aus den Daten ein Bauwerks-Produktmodell abzuleiten und dieses einzelnen Fachplanern – etwa zur Erstellung eines Energiepasses – zugänglich zu machen. Der Aufsatz zeigt den erfolgreichen Einsatz virtueller neuronaler Netze im Bereich der Bestandserfassung anhand eines komplexen Beispiels.

Published
2006
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137. Analysis of building structure and topology based on Graph Theory

Author

van Treeck, Christoph and Rank, Ernst

Abstract

Individual views on a building product of people involved in the design process imply different models for planning and calculation. In order to interpret these geometrical, topological and semantical data of a building model we identify a structural component graph, a graph of room faces, a room graph and a relational object graph as aids and we explain algorithms to derive these relations. The application of the technique presented is demonstrated by the analysis and discretization of a sample model in the scope of building energy simulation.

Published
2004
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138. Interaktive Strömungssimulation auf Hochleistungsrechnern unter Anwendung der Lattice-Boltzmann Methode

Author

van Treeck, Christoph (Prof. Dr. habil.), Rank, Ernst (Prof. Dr.), Hausladen, Gerhard (Prof. Dr.), Pfaffinger, Michael, van Treeck, Christoph (Prof. Dr. habil.), Rank, Ernst (Prof. Dr.), Hausladen, Gerhard (Prof. Dr.), and Pfaffinger, Michael

Abstract

Die Arbeit beschäftigt sich mit interaktiver Simulation von Raumluftströmungen auf Hochleistungsrechnern. Konkret werden thermische Strömungen untersucht, die als Grundlage für eine Behaglichkeitsanalyse dienen können. Hierzu wird das Thema Computational Steering und anschließend die Lattice-Boltzmann Methode als Basis der Strömungssimulation erörtert. Einen wesentlichen Aspekt der Arbeit bildet die Visualisierung der gewonnenen Daten. In einem weiteren Schritt wird die für die Simulation notwendige Parallelisierungsstrategie näher untersucht. Anschließend werden Optimierungsansätze für die Nutzung auf dem Höchstleistungsrechner Bayern II betrachtet und die Leistungsfähigkeit des Simulationscodes an Benchmark-Tests untersucht. Einen weiteren Kernbaustein der Arbeit bildet die Validierung des Simulationscodes anhand von zwei klar definierten Modellen. Abschließend werden zwei mögliche industrielle Anwendungsbeispiele gezeigt., This thesis examines the interactive simulation of indoor air flow using high-performance computers. Particular focus is given to thermal fluid flow, which can serve as a basis for comfort analysis. The dissertation begins by addressing the subject of Computational Steering before examining the Lattice-Boltzmann method as the basis for the computational fluid flow simulation. Another key aspect of this work is the visualization of the obtained data. Here, various issues, including the parallelization strategy which is necessary for the simulation is investigated. Different optimization strategies for use with the high-performance computer Höchstleistungsrechner Bayern II are also examined and the performance of the simulation code tested using benchmark examples in various configurations. Another key aspect of this work is the validation of the simulation code based on two clearly defined benchmark problems. Finally, two potential industrial application examples are shown.

Published
2013

139. Interaktive Strömungssimulation auf Hochleistungsrechnern unter Anwendung der Lattice-Boltzmann Methode

Author

Rank, Ernst (Prof. Dr.), Rank, Ernst (Prof. Dr.);Hausladen, Gerhard (Prof. Dr.);van Treeck, Christoph (Prof. Dr. habil.), Pfaffinger, Michael, Rank, Ernst (Prof. Dr.), Rank, Ernst (Prof. Dr.);Hausladen, Gerhard (Prof. Dr.);van Treeck, Christoph (Prof. Dr. habil.), and Pfaffinger, Michael

Abstract

Die Arbeit beschäftigt sich mit interaktiver Simulation von Raumluftströmungen auf Hochleistungsrechnern. Konkret werden thermische Strömungen untersucht, die als Grundlage für eine Behaglichkeitsanalyse dienen können. Hierzu wird das Thema Computational Steering und anschließend die Lattice-Boltzmann Methode als Basis der Strömungssimulation erörtert. Einen wesentlichen Aspekt der Arbeit bildet die Visualisierung der gewonnenen Daten. In einem weiteren Schritt wird die für die Simulation notwendige Parallelisierungsstrategie näher untersucht. Anschließend werden Optimierungsansätze für die Nutzung auf dem Höchstleistungsrechner Bayern II betrachtet und die Leistungsfähigkeit des Simulationscodes an Benchmark-Tests untersucht. Einen weiteren Kernbaustein der Arbeit bildet die Validierung des Simulationscodes anhand von zwei klar definierten Modellen. Abschließend werden zwei mögliche industrielle Anwendungsbeispiele gezeigt., This thesis examines the interactive simulation of indoor air flow using high-performance computers. Particular focus is given to thermal fluid flow, which can serve as a basis for comfort analysis. The dissertation begins by addressing the subject of Computational Steering before examining the Lattice-Boltzmann method as the basis for the computational fluid flow simulation. Another key aspect of this work is the visualization of the obtained data. Here, various issues, including the parallelization strategy which is necessary for the simulation is investigated. Different optimization strategies for use with the high-performance computer Höchstleistungsrechner Bayern II are also examined and the performance of the simulation code tested using benchmark examples in various configurations. Another key aspect of this work is the validation of the simulation code based on two clearly defined benchmark problems. Finally, two potential industrial application examples are shown.

Published
2013

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