@inproceedings{AimerWirnsbergerKrause2020, author = {Aimer, Dominik and Wirnsberger, Markus and Krause, Harald}, title = {Simulation von L{\"u}ftungssystemen und Entwurf verschiedener Regler f{\"u}r optimierte Luftqualit{\"a}t und Energieeffizienz}, series = {BauSIM 2020 - 8th Conference of IBPSA Germany and Austria 23-25 September 2020, Graz University of Technology, Austria}, booktitle = {BauSIM 2020 - 8th Conference of IBPSA Germany and Austria 23-25 September 2020, Graz University of Technology, Austria}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:861-opus4-16496}, pages = {152 -- 160}, year = {2020}, abstract = {In dieser Arbeit wurden unterschiedliche Regler f{\"u}r Wohnrauml{\"u}ftungsanlagen untersucht. Als Bewertungsgr{\"o}ßen wurden die L{\"u}ftungsw{\"a}rmeverluste und die kumulierte Grenzwert{\"u}berschreitung f{\"u}r CO2 und relative Luftfeuchte verwendet. Daf{\"u}r wurde in Matlab/Simulink ein Multizonen-Simulationsmodell erstellt. Untersucht wurde ein zentrales, ein dezentrales alternierendes (Pendell{\"u}ftung) sowie ein nichtalternierendes (Einzelrauml{\"u}ftung) L{\"u}ftungssystem. Jedes der L{\"u}ftungssysteme wurde mit konstantem Volumenstrom, einem PI- und einem Fuzzy-Regler (Ausnahme: Pendell{\"u}ftung) simuliert. Gegen{\"u}ber einem L{\"u}ftungssystem mit konstantem Volumenstrom, kann durch Regelung bei mindestens gleicher Luftqualit{\"a}t der L{\"u}ftungsw{\"a}rmeverlust um mindestens ein Drittel reduziert werden.}, language = {de} } @inproceedings{WirnsbergerKuefnerKrause2019, author = {Wirnsberger, Markus and K{\"u}fner, Marcel and Krause, Harald}, title = {Ventilation Efficiency Of Push-Pull Ventilation Systems In Residential Buildings - CFD Simulation And Validation Of The Model With Measurements In A Research Apartment}, series = {Proceedings of the 16th IBPSA Conference Rome, Italy, Sept. 2-4, 2019}, booktitle = {Proceedings of the 16th IBPSA Conference Rome, Italy, Sept. 2-4, 2019}, pages = {785 -- 790}, year = {2019}, abstract = {In the project, domestic ventilation concepts with PushPull-Fans were investigated. These ventilation units are characterized by a periodically changing supply and exhaust air operation. To ensure balanced operation, these ventilation units are always used in pairs, with one unit being in the exhaust air mode and the other in supply air mode. Measurements were made in a research apartment. The results were used to validate a CFD simulation model for transient studies. A room-by-room layout with two units in one room and a cross-room ventilation layout with two connected units in two rooms were analysed. The age of air was used as the evaluation parameter. With the room-by-room ventilation layout a lower age of air in the bedroom compared to the cross-room layout was obtained. However, in the room-by-room layout, the air flow through the larger living room with connected corridor was poorer in the rear area. With the cross-room layout, the flow through the rooms was more uniform. With the cross-room layout, the average age of air in the apartment could be slightly reduced compared to the room-by-room layout.}, language = {en} } @article{MagniOchsdeVriesetal.2021, author = {Magni, Mara and Ochs, Fabian and de Vries, Samuel and Maccarini, Alessandro and Sigg, Ferdinand}, title = {Detailed cross comparison of building energy simulation tools results using a reference office building as a case study}, series = {Energy and Buildings}, volume = {250}, journal = {Energy and Buildings}, pages = {111260}, year = {2021}, abstract = {Building Energy Simulation (BES) tools play a key role in the optimization of the building system during the different phases, from pre-design through commissioning to operation. BES tools are increasingly used in research as well as in companies. New BES tools and updated versions are continuously being released. Each tool follows an independent validation process but rarely all the tools are compared against each other using a common case study. In this work, the modelling approaches of widespread dynamic simulation tools (i.e. EnergyPlus, TRNSYS, Simulink libraries CarnotUIBK and ALMABuild, IDA ICE, Modelica/Dymola and DALEC), as well as PHPP (a well-known quasi-steady-state tool), are described and the results of all the tools modelling the same characteristic office cell, defined within the IEA SHC Task 56, are compared on a monthly and hourly basis for the climates of Stockholm, Stuttgart and Rome. Unfortunately, different tools require different levels of input detail, which are often not matching with available data, hence the parametrization process highly influences the quality of the simulation results. In the current study to evaluate the deviation between the tools, frequently used statistical indices and normalization methods are analysed and the problems related to their application, in a cross-comparison of different tools, are investigated. In this regard, the deviation thresholds indicated by ASHRAE Guideline 14-2014 are used as a basis to identify results that suggest an acceptable level of disagreement between the predictions of a particular model and the outcomes of all models. The process of reaching a good agreement between all tools required several iterations and great effort on behalf of the modellers. To aid the definition of building component descriptions and future references for inter-model comparison a short history of the executed steps is presented in this work. Together with the comparison of the results of the tools, their computational cost is evaluated and an overview of the modelling approaches supported by the different tools for this case study is provided aiming to support the users in choosing a fit-for-purpose simulation tool.}, language = {en} } @phdthesis{Schoepfer2019, author = {Sch{\"o}pfer, Fabian}, title = {Vibroacoustics of timber-frame structures excited by structure-borne sound sources}, school = {Technische Hochschule Rosenheim}, year = {2019}, abstract = {This thesis investigates the measurement and prediction of machinery noise in timber-frame buildings. To quantify the structure-borne sound power input from multi-point sources, simplified approaches were assessed that reduce the required data for out-of-plane force excitation. This identified approaches that give estimates within ±5 dB from 20 Hz to 2000 Hz. To investigative the importance of out-of-plane moment excitation, inverse methods were used to determine the power input; these were affected by noise but processing was used to overcome this shortcoming. A series of experimental investigations were carried out on a timber-frame structure undergoing mechanical point excitation. The driving-point mobility showed orthotropic plate characteristics at low frequencies, ribbed-plate characteristics in a narrow frequency band and infinite plate characteristics in mid- and high-frequency ranges. The moment mobility above or in-between studs was similar to infinite beam or plate theory with interpolation between these theories where necessary. The experimental work indicated the potential to use Statistical Energy Analysis (SEA) to predict sound transmission. The first experimental finding was that above the mass-spring-mass resonance frequency, the vibrational response of the wall leaves was uncorrelated. The second was a significant decrease in vibration across the wall from the excitation point, with structural intensity showing a decrease in net power flow across successive timber studs. The third was that tongue and groove connections between chipboard sheets significantly reduce the vibration transmission above 500 Hz. This led to different SEA models being used to model a timber-frame wall undergoing mechanical point excitation. A 41-subsystem model was found to be necessary to reproduce the measured vibration levels on both leaves within 10 dB. As there is a significant decrease in vibration with distance in the mid- and high-frequency range, the region close to the excitation point is particularly important and the SEA model has better accuracy in this region. An alternative engineering approach to the prediction of machinery noise in timber-frame buildings was introduced and validated that used measured transmission functions between the injected power and the spatial-average sound pressure level in a receiving room. A field survey and case studies indicate this is a feasible and practical approach.}, language = {en} } @techreport{BietzHuberMeckingetal.2020, author = {Bietz, Heinrich and Huber, Anton and Mecking, Simon and Rabold, Andreas and Schmelzer, Martin and Sgrieß, Daniel and Wittstock, Volker}, title = {Mehr als nur D{\"a}mmung - Zusatznutzen von D{\"a}mmstoffen aus nachwachsenden Rohstoffen (NawaRo-D{\"a}mmstoffe), Schlussbericht zum Arbeitsbereich 2 Schallschutz}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:861-opus4-31201}, pages = {397}, year = {2020}, abstract = {Der Arbeitsbereich 2 des Verbundvorhabens hatte als Ziel, die Anwendbarkeit von D{\"a}mmstoffen aus nachwachsenden Rohstoffen unter dem Aspekt des Schallschutzes deutlich zu erh{\"o}hen. Ein zentrales technisches Ergebnis des Projektes stellt der erweiterte Bauteilkatalog f{\"u}r Holzbauteile dar, der eine umfangreiche Sammlung an Planungsdaten bietet. Dieser wurde auf Basis der Analyse und Aufbereitung vorhandener Messdaten sowie der im Projekt durchgef{\"u}hrten Pr{\"u}fungen erstellt. Innerhalb des Projektes wurden • 45 Deckenaufbauten und • 10 Wandkonstruktionen hinsichtlich ihrer schalltechnischen Eigenschaften untersucht. Dabei wurden Holztafelkonstruktionen und Massivholzkonstruktionen ber{\"u}cksichtigt. Die ermittelten Werte zeigen, dass mit den Deckenaufbauten beim Einsatz von Holzfaser-Trittschalld{\"a}mmplatten sehr gute Ergebnisse erreichbar sind. Bei entsprechender Gesamtkonstruktion k{\"o}nnen somit auch mit steiferen NawaRo-D{\"a}mmplatten die Zielwerte f{\"u}r Trenndecken eingehalten werden. Neben der Entwicklung dieser speziell f{\"u}r NawaRo-D{\"a}mmstoffe optimierten Aufbauten, konnte f{\"u}r den gesamten Bauteilkatalog eine {\"O}ffnung f{\"u}r Hohlraumd{\"a}mmstoffe aus nachwachsenden Rohstoffen erreicht werden. NawaRo-D{\"a}mmstoffe zur Hohlraumd{\"a}mpfung sollten dabei einen l{\"a}ngenbezogenen Str{\"o}mungswiderstand zwischen 5 kPa s/m² und 50 kPa s/m² und eine offene Porosit{\"a}t gr{\"o}ßer als 0,9 (entspricht bei den meisten untersuchten D{\"a}mmstoffen etwa einer Rohdichte ≤ 130 kg/m³) aufweisen. Zus{\"a}tzliche Messungen mit h{\"o}herer fl{\"a}chenbezogener Masse der Unterdecke zeigten den positiven Einfluss von brandschutz-technisch erforderlichen Zusatzbeplankungen gerade bei den besonders interessierenden tiefen Frequenzen. Ein wissenschaftliches Ergebnis des Projektes ist in der Weiterentwicklung der Simulationsmodelle f{\"u}r die Schall{\"u}bertragung zu sehen. Hierzu konnten die semianalytischen Modelle f{\"u}r die Ber{\"u}cksichtigung der Materialeigenschaften unterschiedlicher Hohlraumd{\"a}mmstoffe erweitert werden. Als zweites Simulationsmodell wurde die Finite-Elemente-Methode f{\"u}r die Berechnung der Schalld{\"a}mmung eingesetzt. F{\"u}r die Simulation wurde ein Massivholz-Wandelement mit W{\"a}rmed{\"a}mm-Verbund-System als Außenwand modelliert. Diese Außenwandkonstruktion ist von besonderem Interesse, da sie im mehrgeschossigen Wohnungsbau gerne verwendet wird, aber sowohl im Brandschutz als auch im Schallschutz noch Optimierungsbedarf aufweist.}, language = {de} }