TY - JOUR A1 - Alsaad, Hayder A1 - Hartmann, Maria A1 - Hilbel, Rebecca A1 - Völker, Conrad T1 - ENVI-met validation data accompanied with simulation data of the impact of facade greening on the urban microclimate JF - Data in Brief N2 - This dataset consists mainly of two subsets. The first subset includes measurements and simulation data conducted to validate the simulation tool ENVI-met. The measurements were conducted at the campus of the Bauhaus-University Weimar in Weimar, Germany and consisted of recording exterior air temperature, globe temperature, relative humidity, and wind velocity at 1.5 m at four points on four different days. After the measurements, the geometry of the campus was modelled and meshed; the simulations were conducted using the weather data of the measurements days with the aim of investigating the accuracy of the model. The second data subset consists of ENVI-met simulation data of the potential of facade greening in improving the outdoor environment and the indoor air temperature during heatwaves in Central European cities. The data consist of the boundary conditions and the simulation output of two simulation models: with and without facade greening. The geometry of the models corresponded to a residential buildings district in Stuttgart, Germany. The simulation output consisted of exterior air temperature, mean radiant temperature, relative humidity, and wind velocity at 12 different probe points in the model in addition to the indoor air temperature of an exemplary building. The dataset presents both vertical profiles of the probed parameters as well as the time series output of the five-day simulation duration. Both data subsets correspond to the investigations presented in the co-submitted article [1]. KW - Messung KW - Measurements KW - Simulations KW - ENVI-met KW - Living wall KW - Green facade KW - Simulation KW - OA-Publikationsfonds2022 Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20220511-46455 UR - https://www.sciencedirect.com/science/article/pii/S2352340922004048#! VL - 2022 IS - Volume 42, article 108200 SP - 1 EP - 13 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Alsaad, Hayder A1 - Hartmann, Maria A1 - Völker, Conrad T1 - Hygrothermal simulation data of a living wall system for decentralized greywater treatment JF - Data in Brief N2 - This dataset presents the numerical analysis of the heat and moisture transport through a facade equipped with a living wall system designated for greywater treatment. While such greening systems provide many environmental benefits, they involve pumping large quantities of water onto the wall assembly, which can increase the risk of moisture in the wall as well as impaired energetic performance due to increased thermal conductivity with increased moisture content in the building materials. This dataset was acquired through numerical simulation using the coupling of two simulation tools, namely Envi-Met and Delphin. This coupling was used to include the complex role the plants play in shaping the near-wall environmental parameters in the hygrothermal simulations. Four different wall assemblies were investigated, each assembly was assessed twice: with and without the living wall. The presented data include the input and output parameters of the simulations, which were presented in the co-submitted article [1]. KW - Kupplung KW - Feuchteleitung KW - Heat transport KW - Moisture transport KW - Living wall KW - Wärmeübertragung KW - coupling KW - ENVI-Met KW - Delphin KW - OA-Publikationsfonds2022 Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20220106-45483 UR - https://www.sciencedirect.com/science/article/pii/S2352340921010167?via%3Dihub VL - 2022 IS - volume 40, article 107741 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Dokhanchi, Najmeh Sadat A1 - Arnold, Jörg A1 - Vogel, Albert A1 - Völker, Conrad T1 - Measurement of indoor air temperature distribution using acoustic travel-time tomography: Optimization of transducers location and sound-ray coverage of the room JF - Measurement N2 - Acoustic travel-time TOMography (ATOM) allows the measurement and reconstruction of air temperature distributions. Due to limiting factors, such as the challenge of travel-time estimation of the early reflections in the room impulse response, which heavily depends on the position of transducers inside the measurement area, ATOM is applied mainly outdoors. To apply ATOM in buildings, this paper presents a numerical solution to optimize the positions of transducers. This optimization avoids reflection overlaps, leading to distinguishable travel-times in the impulse response reflectogram. To increase the accuracy of the measured temperature within tomographic voxels, an additional function is employed to the proposed numerical method to minimize the number of sound-path-free voxels, ensuring the best sound-ray coverage of the room. Subsequently, an experimental set-up has been performed to verify the proposed numerical method. The results indicate the positive impact of the optimal positions of transducers on the distribution of ATOM-temperatures. KW - Bauphysik KW - Bauklimatik KW - Akustische Laufzeit-Tomographie Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20220524-46473 UR - https://www.sciencedirect.com/science/article/abs/pii/S0263224120304723?via%3Dihub VL - 2020 IS - Volume 164, article 107934 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Alsaad, Hayder A1 - Völker, Conrad T1 - Measuring and visualizing the flow supplied by personalized ventilation T2 - Proceedings Book Roomvent 2020 N2 - This study investigates the flow supplied by personalized ventilation (PV) by means of anemometer measurements and schlieren visualization. The study was conducted using a thermal manikin to simulate a seated occupant facing a PV outlet. Air velocity was measured at multiple points in the flow field; the collected velocity values were used to calculate the turbulence intensity. Results indicated that PV was supplying air with low turbulence intensity that was able to penetrate the convective boundary layer of the manikin to supply clean air for inhalation. The convective boundary layer, however, obstructed the supplied flow and reduced its velocity by a total of 0.26 m/s. The PV flow preserved its value until about 10 cm from the face where velocity started to drop. Further investigations were conducted to test a PV diffuser with a relatively large outlet diameter (18 cm). This diffuser was developed using 3d-modelling and 3d-printing. The diffuser successfully distributed the flow over the larger outlet area. However, the supplied velocity and turbulence fields were not uniform across the section. KW - Belüftung KW - Luftqualität KW - Personalized ventilation KW - Schlieren imaging KW - Air quality KW - Thermal manikin Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20220622-46573 CY - Turin, Italy ER - TY - JOUR A1 - Völker, Conrad A1 - Mämpel, Silvio A1 - Kornadt, Oliver T1 - Measuring the human body’s micro‐climate using a thermal manikin JF - Indoor Air N2 - The human body is surrounded by a micro‐climate which results from its convective release of heat. In this study, the air temperature and flow velocity of this micro‐climate were measured in a climate chamber at various room temperatures, using a thermal manikin simulating the heat release of the human being. Different techniques (Particle Streak Tracking, thermography, anemometry, and thermistors) were used for measurement and visualization. The manikin surface temperature was adjusted to the particular indoor climate based on simulations with a thermoregulation model (UCBerkeley Thermal Comfort Model). We found that generally, the micro‐climate is thinner at the lower part of the torso, but expands going up. At the head, there is a relatively thick thermal layer, which results in an ascending plume above the head. However, the micro‐climate shape strongly depends not only on the body segment, but also on boundary conditions: the higher the temperature difference between the surface temperature of the manikin and the air temperature, the faster the air flow in the micro‐climate. Finally, convective heat transfer coefficients strongly increase with falling room temperature, while radiative heat transfer coefficients decrease. The type of body segment strongly influences the convective heat transfer coefficient, while only minimally influencing the radiative heat transfer coefficient. KW - Raumklima KW - Mikroklima KW - Wärmeübertragung KW - Strömungsmechanik KW - thermal manikin KW - climate chamber KW - micro climate KW - heat transfer coefficient KW - CFD KW - thermography Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20181025-38153 UR - https://onlinelibrary.wiley.com/doi/abs/10.1111/ina.12112 N1 - This is the peer reviewed version of the following article: "Measuring the human body’s micro‐climate using a thermal manikin", which has been published in final form at https://doi.org/10.1111/ina.12112. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. IS - 24, 6 SP - 567 EP - 579 ER - TY - INPR A1 - Vogel, Albert A1 - Völker, Conrad A1 - Bode, Matthias A1 - Marx, Steffen T1 - Messung und Simulation der Erwärmung von ermüdungsbeanspruchten Betonprobekörpern T2 - Bauphysik N2 - Im vorliegenden Beitrag werden Messungen und Berechnungen vorgestellt, die die Temperaturentwicklung in Betonzylindern aufgrund zyklischer Beanspruchung genau beschreiben. Die Messungen wurden in einem Versuchsstand, die Berechnungen im FEM-Programm ANSYS durchgeführt. Mit Hilfe der Temperaturmessungen konnten die Simulationen für die Temperaturentwicklung der Betonzylinder mit der verwendeten Betonrezeptur validiert werden. Die Untersuchungen lassen den Schluss zu, dass bei zyklischer Probekörperbelastung und der einhergehenden Probekörperdehnung Energie dissipiert wird und diese maßgeblich für die Erwärmung der Probe verantwortlich ist. N2 - This paper presents measurements and simulations that describe the temperature development in concrete cylinders due to cyclic loading. The measurements were carried out in a test stand, the simulations in the FEM program ANSYS. The simulations of the temperature development in the concrete cylinders with the used concrete recipe were validated using the temperature measurements. The investigations lead to the conclusion that energy is dissipated during cyclic test specimen loading and the accompanying test specimen elongation and that this is mainly responsible for the heating of the specimen. KW - zyklische Beanspruchung KW - Ermüdung KW - Dissipation KW - zyklische Beanspruchung KW - Ermüdung KW - Dissipation KW - cyclic load KW - fatigue Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20200425-41471 UR - https://onlinelibrary.wiley.com/doi/abs/10.1002/bapi.201900031 N1 - This is the pre-peer reviewed version of the following article: hhttps://onlinelibrary.wiley.com/doi/abs/10.1002/bapi.201900031, which has been published in final form at https://doi.org/10.1002/bapi.201900031. VL - 2020 IS - Volume 42, Issue 2 SP - 86 EP - 93 PB - John Wiley and Sons ER - TY - RPRT A1 - Vogel, Albert A1 - Völker, Conrad A1 - Arnold, Jörg A1 - Schmidt, Jens A1 - Thurow, Torsten A1 - Braunes, Jörg A1 - Tonn, Christian A1 - Bode, Kay-André A1 - Baldy, Franziska A1 - Erfurt, Wolfgang A1 - Tatarin, René T1 - Methoden und Baustoffe zur nutzerorientierten Bausanierung. Schlussbericht zum InnoProfile Forschungsvorhaben N2 - Nutzerorientierte Bausanierung bedeutet eine gegenüber dem konventionellen Vorgehen deutlich verstärkte Ausrichtung des Planungs- und Sanierungsprozesses auf die Anforderungen und Bedürfnisse des zukünftigen Nutzers eines Gebäudes. Dies hat einerseits ein hochwertigeres Produkt zum Ergebnis, erfordert andererseits aber auch den Einsatz neuer Methoden und Baustoffe sowie ein vernetztes Zusammenarbeiten aller am Bauprozess Beteiligten. Der Fokus der Publikation liegt dabei auf den Bereichen, die eine hohe Relevanz für die nutzerorientierte Bausanierung aufweisen. Dabei handelt es sich insbesondere um: Computergestütztes Bauaufmaß und digitale Bauwerksmodellierung (BIM), bauphysikalische Methoden zur Optimierung von Energieeffizienz und Behaglichkeit bei der Sanierung von Bestandsgebäuden, zerstörungsfreie Untersuchungsmethoden im Rahmen einer substanzschonenden Bauzustandsanalyse und Entwicklung von Ergänzungsbaustoffen. Das Projekt nuBau ist eine Kooperation zwischen den Fakultäten Bauingenieurwesen und Architektur der Bauhaus-Universität Weimar. Die beteiligten Professuren sind: Bauphysik, Informatik in der Architektur, Polymere Werkstoffe und Werkstoffe des Bauens. T3 - Schriftenreihe der Professur Bauphysik - 5 KW - Nutzerorientierte Bausanierung KW - BIM KW - zerstörungsfreie Prüfung KW - bauphysikalische Methoden KW - Ergänzungsbaustoffe Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20130830-20229 UR - http://www.uni-weimar.de/cms/bauing/projekte/nubau/home.html SN - 978-3-86068-501-3 (Printausg.) ER - TY - JOUR A1 - Völker, Conrad A1 - Beckmann, Julia A1 - Koehlmann, Sandra A1 - Kornadt, Oliver T1 - Occupant requirements in residential buildings – an empirical study and a theoretical model JF - Advances in Building Energy Research N2 - Occupant needs with regard to residential buildings are not well known due to a lack of representative scientific studies. To improve the lack of data, a large scale study was carried out using a Post Occupancy Evaluation of 1,416 building occupants. Several criteria describing the needs of occupants were evaluated with regard to their subjective level of relevance. Additionally, we investigated the degree to which deficiencies subjectively exist, and the degree to which occupants were able to accept them. From the data obtained, a hierarchy of criteria was created. It was found that building occupants ranked the physiological needs of air quality and thermal comfort the highest. Health hazards such as mould and contaminated building materials were unacceptable for occupants, while other deficiencies were more likely to be tolerated. Occupant satisfaction was also investigated. We found that most occupants can be classified as satisfied, although some differences do exist between different populations. To explain the relationship between the constructs of what we call relevance, acceptance, deficiency and satisfaction, we then created an explanatory model. Using correlation and regression analysis, the validity of the model was then confirmed by applying the collected data. The results of the study are both relevant in shaping further research and in providing guidance on how to maximize tenant satisfaction in real estate management. KW - Post Occupancy Evaluation KW - Gebäude KW - Benutzung KW - occupant requirements KW - occupant satisfaction KW - residential buildings KW - housing KW - questionnaire Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20181015-38137 UR - https://www.tandfonline.com/doi/abs/10.1080/17512549.2012.749808 N1 - This is an Accepted Manuscript of an article published by Taylor & Francis in Advances in Building Energy Research on 29/01/2013, available online: https://www.tandfonline.com/doi/abs/10.1080/17512549.2012.749808. IS - 7 (1) SP - 35 EP - 50 ER - TY - JOUR A1 - Alsaad, Hayder A1 - Völker, Conrad T1 - Performance assessment of a ductless personalized ventilation system using a validated CFD model JF - Journal of Building Performance Simulation N2 - The aim of this study is twofold: to validate a computational fluid dynamics (CFD) model, and then to use the validated model to evaluate the performance of a ductless personalized ventilation (DPV) system. To validate the numerical model, a series of measurements was conducted in a climate chamber equipped with a thermal manikin. Various turbulence models, settings, and options were tested; simulation results were compared to the measured data to determine the turbulence model and solver settings that achieve the best agreement between the measured and simulated values. Subsequently, the validated CFD model was then used to evaluate the thermal environment and indoor air quality in a room equipped with a DPV system combined with displacement ventilation. Results from the numerical model were then used to quantify thermal sensation and comfort using the UC Berkeley thermal comfort model. KW - Ventilation KW - Validierung KW - Strömungsmechanik KW - Raumklima KW - personalized ventilation KW - validation KW - computational fluid dynamics KW - thermal comfort KW - indoor air quality Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20190218-38500 UR - https://www.tandfonline.com/doi/full/10.1080/19401493.2018.1431806 N1 - Copyright 2018 Taylor & Francis Group and the International Building Performance Simulation Association (IBPSA). This article may be downloaded for personal use only. Any other use requires prior permission of the authors and Taylor & Francis Group. This is an Accepted Manuscript of an article published by Taylor & Francis in the Journal of Building Performance Simulation 11 (6), 689–704 (2018) and may be found at https://doi.org/10.1080/19401493.2018.1431806 VL - 2018 IS - 11, Heft 6 SP - 689 EP - 704 ER - TY - JOUR A1 - Alsaad, Hayder A1 - Völker, Conrad T1 - Performance evaluation of ductless personalized ventilation in comparison with desk fans using numerical simulations JF - Indoor Air N2 - The performance of ductless personalized ventilation (DPV) was compared to the performance of a typical desk fan since they are both stand-alone systems that allow the users to personalize their indoor environment. The two systems were evaluated using a validated computational fluid dynamics (CFD) model of an office room occupied by two users. To investigate the impact of DPV and the fan on the inhaled air quality, two types of contamination sources were modelled in the domain: an active source and a passive source. Additionally, the influence of the compared systems on thermal comfort was assessed using the coupling of CFD with the comfort model developed by the University of California, Berkeley (UCB model). Results indicated that DPV performed generally better than the desk fan. It provided better thermal comfort and showed a superior performance in removing the exhaled contaminants. However, the desk fan performed better in removing the contaminants emitted from a passive source near the floor level. This indicates that the performance of DPV and desk fans depends highly on the location of the contamination source. Moreover, the simulations showed that both systems increased the spread of exhaled contamination when used by the source occupant. KW - Behaglichkeit KW - Raumklima KW - Strömungsmechanik KW - Fluid KW - computational fluid dynamics KW - desk fan KW - ductless personalized ventilation KW - IAQ KW - thermal comfort Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20200422-41407 UR - https://onlinelibrary.wiley.com/doi/full/10.1111/ina.12672 VL - 2020 PB - John Wiley & Sons Ltd ER -