Indoor simulations
Final Report Abstract
In the context of the Research Unit UCaHS addressing complex scientific questions related to heat stress in mid-latitude cities, Research Module (RM) 2.2 "Indoor simulations" was responsible for the development of a simulation-based approach to study indoor heat stress risks. Two three-dimensional thermal room modeling approaches were used to implement Indoor Climate System Models. Highresolution 3D-room simulations were realized within the Software ANSYS CFD, and the zonal approach was new developed using the modeling language Modelica. The development, validation and applications of both simulation models leads us to the answers regarding the formulated research questions: CFD studies offer valuable detailed information but they are still restricted to very short time periods, like minutes, or stationary observations. Their results were used for analysing heat stress scenarios in detail and for cross-validation. The development of the zonal model, designed and implemented in the object-oriented modeling language Modelica, enables us to do spatial resolved simulations covering medium time periods up to several days. In contrast to CFD calculations, the results are much less spatially resolved but seem to be suitable for providing all of the information necessary to assess indoor heat stress risks. The zonal approach implemented in an objectoriented language seems to be the best choice to integrate various models of air conditioning technologies. Due to first simulation results and to the changed composition of the research group, parts of the original focus needed to be shifted. The analysis of various room designs was neglected, the study of building design and A/C-solutions was reduced. User behavior patterns were increasingly considered. The ability of the zonal models to compute rooms spatially resolved in 150 - 350 zones over time periods of up to 10 days in a reasonable amount of time creates ideal preconditions for including and analyzing different building-types, room geometries, ventilation types and user behavior. In combination with a dynamic adaptive assessment model for heat stress risks this extends static heat stress assessment methods ('room-climate point of view') to dynamic and human-centered heat stress risk assessment methods ('human point of view'). The zonal approach and the steps taken in the application to real-sized rooms were well documented. First verifications, the calibration approach, and further validations leading to the simulation of real rooms and the combined simulation with a physiological human response model were published at conferences. Parts of the project code have been integrated into the free and open source library BuildingSystems. More parts of the zonal model including application examples will be published as free and open-source project code in the context of a dissertation. The results and experience made during the research project are going to be used in further research projects. In particular, the zonal approach is going to act as part of a joint energetic building model in Modelica, in which the spatial resolution and the employed physical model can be flexibly adapted to the simulation problem. Through the use of Modelica's object-oriented approach different spatial resolutions (0D, 1D, 3D) for the individual parts of a multi-zone-building model are feasible, as are mixed thermal and hygro-thermal building models.
Publications
-
(2014): Ein simulationsbasierter Ansatz zur Analyse von Hitzestressereignissen in Innenräumen. Proceedings of the 5th German-Austrian Conference of the International Building Performance Simulation Association, 22-24 September, Aachen, Germany. ISBN: 978-3-00-047160-5
Mucha K., Nytsch-Geusen C., Streuling C.
-
(2014): Entwicklung eines räumlich und physikalisch adaptiven energetischen Gebäudemodells in Modelica. Proceedings of the 5th German- Austrian Conference of the International Building Performance Simulation Association, 22-24 September, Aachen, Germany. ISBN: 978-3-00-047160-5
Nytsch-Geusen, C.; Inderfurth, A.; Mucha, K.; Rädler, J.
-
(2015): A zonal room model in combined simulation with a physiological human response model to quantify indoor heat stress risks. Proceedings of the 14th International Conference of the International Building Performance Simulation Association, 7-9 December, Hyderabad, India. ISBN: 978-93-5230-118-8
Mucha K., Nytsch-Geusen, C., Wölki D., and van Treeck C.
-
(2017): Ein Simulationsansatz zur Bewertung von Hitzestressrisiken in Innenräumen. Weiterentwicklung eines zonalen Modells in Modelica. Dissertation an der Universität der Künste Berlin, Fakultät Gestaltung, Berlin
Mucha, K.
