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Copyright of Bauphysik is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This series of articles presents the use of computer programmes in university teaching of building physics and building technology for architects and civil engineers. The Department of Building Physics/Energy‐efficient Buildings (Faculty of Civil Engineering) at the RPTU in Kaiserslautern offers lectures and seminars for students of civil engineering (Bachelor and Master) and for students of architecture (Bachelor). In addition, courses are offered for other degree programmes. Software tools are mainly used in the specialisation module "Building Physics – Energy Efficiency and Modeling" of the Master's programme "Structural Engineering" in Civil Engineering. Students are introduced to the basics of building physics modeling and simulation. The focus of the courses is to acquire the methodological competence of learning and correctly using simulation programmes and to deepen the understanding of building physics processes in components, rooms and buildings. [ABSTRACT FROM AUTHOR]

The room‐side heat transfer of a building is essential for calculating and simulating heat loss through radiation and convection in interior spaces, and also for preventing mould growth and condensation. By means of Computational Fluid Dynamics (CFD) simulations, this study investigates the effect of floor heating, mixing ventilation, furniture, room geometry, and their combinations on the interior heat transfer coefficient (HTC) of a typical office room. The results show an inhomogeneous distribution of the HTC on the exterior walls. HTC values are generally below the German standardised value for thermal protection, which means an overestimation of the heat loss when the standardised value is applied. However, compared to the standardised value for preventing mould growth, the minimum surface‐averaged HTC behind closets is 63 % lower, potentially leading to mould growth and condensation. [ABSTRACT FROM AUTHOR]

• Heat transfer characteristics were analysed at the wall surfaces and room edges. • Thermal bridge and inhomogeneous wall surface temperature were considered. • Comprehensive heat transfer correlation models were developed. • Existing models show discrepancies up to 96.5%. • The developed models can improve the accuracy in predicting energy performance. Heat transfer analysis is crucial for precise energy performance estimates in buildings with floor heating systems. However, existing models for predicting heat transfer at wall surfaces often lack accuracy, overlooking realistic room conditions such as corners, edges, thermal bridges, and inhomogeneous wall temperatures, thus compromising energy performance prediction. This research develops more comprehensive correlation models for heat transfer coefficients that incorporate a broader range of realistic room configurations, including room volume, floor aspect ratio, and thermal transmittance of exterior walls—factors rarely explored collectively. This study conducts computational fluid dynamics simulations to analyse the radiative and convective heat transfer and applies thermal boundary layer theory to enhance the understanding of the convective heat transfer at room edges. Results indicate that the convective heat transfer is heavily influenced by changes in thermal boundary layer structures at room edges and depends greatly on the hydraulic diameter assumed for the walls. For the radiative heat transfer, the floor aspect ratio proved crucial. The newly developed models reveal deviations up to 96.5 % from existing ones, highlighting the limited applicability of the existing models. The developed models can enhance the accuracy in predicting the energy performance of buildings with floor heating systems. [ABSTRACT FROM AUTHOR]

Normative vs. realistic ventilation behaviour – effect of different ventilation strategies on the energy demand User behaviour can cause a large discrepancy between the calculated energy demand and the actual energy consumption of buildings. In a project funded by the Zukunft Bau research initiative, the room set point temperature was found to be the greatest influencing factor. Based on these results, the influence of different ventilation strategies on the energy demand was investigated. For this purpose, different ventilation pro‐files reflecting different times of presence in the building were simulated in a thermal building simulation program with hourly variable outdoor climate conditions and compared with standard‐compliant calculations. It has been shown that, compared to the permanent ventilation assumed by the standard, intermittent ventilation results in a considerable saving of useful heat energy, however, the number of ventilation processes plays a minor role. The comparison with measurements of the energy consumption in the building shows that the usage profiles with realistic ventilation behaviour show a significantly smaller discrepancy than the norm‐compliant usage profile. [ABSTRACT FROM AUTHOR]

Copyright of Bauphysik is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Multipor WI is a mineral‐based interior insulation system with excellent insulation properties. It is dimensionally stable, vapor permeable, and nonflammable. In this paper the investigation of the processability and functionality of Multipor WI WLF 042 as an exterior insulation system is reported. On the campus of Technische Universität Kaiserslautern, a building was constructed with a new exterior insulation system of Multipor WI WLF 042, of 14 cm thickness. This insulation, which has so far only been used in the building interior, has a heat conductivity of λ = 0.042 W/(mK) and a density of ρ = 90 kg/m3. Its thermal expansion coefficient is α = 10–5/K and its specific heat capacity is c = 0.85 kJ/(kgK). It has a lower density and compression strength than Multipor mineral insulation boards for exterior use do. Temperature sensors were implemented in different layers of the building envelope, both in undisturbed areas and at thermal bridges. The building will be monitored for several years. First heat transfer simulations of two thermal bridges of the building demonstrate the excellent insulation properties of WI WLF 042. The investigation of the processability and functionality of Multipor WI WLF 042 as an exterior insulation system is presented. First simulations show the excellent insulation properties of the insulation. The building will be monitored for several years to provide data about the processability and functionality of Multipor WI WLF 042 as an exterior insulation system. [ABSTRACT FROM AUTHOR]

Copyright of Mauerwerk is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Background: Multipor WI is a mineral‐based interior insulation system with excellent insulation properties. It is dimensionally stable, vapor permeable, and nonflammable. Aims: In this paper the investigation of the processability and functionality of Multipor WI WLF 042 as an exterior insulation system is reported. Materials & Methods: On the campus of Technische Universität Kaiserslautern, a building was constructed with a new exterior insulation system of Multipor WI WLF 042, of 14 cm thickness. This insulation, which has so far only been used in the building interior, has a heat conductivity of λ = 0.042 W/(mK) and a density of ρ = 90 kg/m3. Its thermal expansion coefficient is α = 10−5/K and its specific heat capacity is c = 0.85 kJ/(kgK). It has a lower density and compression strength than Multipor mineral insulation boards for exterior use do. Results: Temperature sensors will be implemented in different layers of the building envelope, both in undisturbed areas and at thermal bridges. The building will be monitored for several years. First heat transfer simulations of two thermal bridges of the building demonstrate the excellent insulation properties of WI WLF 042. Discussion: The investigation of the processability and functionality of Multipor WI WLF 042 as an exterior insulation system is presented. First simulations show the excellent insulation properties of the insulation. Conclusion: The building will be monitored for several years to provide data about the processability and functionality of Multipor WI WLF 042 as an exterior insulation system. [ABSTRACT FROM AUTHOR]

Abstract: Switchable thermal insulation – a theoretical approach Conventional thermal insulation leads to thermal decoupling of the outdoor and indoor climate. In order to limit heat transmission losses this is very useful, however, the thermal insulation is static in comparison to the dynamically changing outdoor climate. Adapting the insulation effect to the respective ambient conditions can contribute to a decrease in heating energy demands of buildings on the one hand, as well as to a reduction of overheating in summer on the other hand. In the first case, a reduced insulation of external building components is useful if there is a high outdoor temperature or high solar radiation onto the facade during the heating period. In the second case, during cool summer nights the reduced insulation leads to an emission of surplus heat from the building interior by heat transmission into the environment. In this work, various methods of switchable thermal insulation are presented and discussed. The potential capacity of switchable thermal insulation for heating as well as for a reduction of overheating in summer is investigated using simulation calculations. To this end, an idealised switchable thermal insulation was examined for which both effects could be established. The saving in heating energy is in the single digits. To evaluate the magnitude of the reduction of overheating in summer it was compared to increased night ventilation. [ABSTRACT FROM AUTHOR]

Innovative sustainable and decentralised energy systems have the potential to contribute significantly to energy saving and carbon emission reduction in the building sector. This article discusses the evaluation of such a novel decentralised heating and cooling system based on small thermoelectric heat pumps called Peltier elements, focusing on its energy efficiency. Experimental studies on the performance of a prototype façade system in outdoor conditions were performed. Based on the results of these experimental studies, thermal simulations were performed using the thermal building simulation program TRNSYS. Combining the results of the outdoor evaluations with those of the building simulations, the energy performance of the developed façade system could be evaluated. It was found that the demand for electrical energy was about 10% higher than that for heating energy, showing that the designed façade system cannot be operated with sufficient efficiency and therefore is not a sustainable alternative to commercially available systems at the current state of the art. [ABSTRACT FROM AUTHOR]

Air conditioning through prefabricated sandwich ceilings containing phase change materials. In this article the development and testing of a novel air-conditioning system using phase-change materials (PCM) is reported. The main principle is to store excess heat of the building interior into macro-encapsulated PCM which is integrated in the sandwich ceiling. The PCM increases the heat storage capacity of the building component in the relevant temperature range by a factor of greater than 10 and almost completely reduces a rise in building component temperature in the temperature range of the phase change of the PCM. In this way an overheating of the room can be counteracted. The presented results of extensive laboratory experiments document the basic functionality of the system regarding workability, cycle stability of the PCM and lowering of air temperature. It could be shown that operating in cyclic day-night mode a reduction of the air temperature by 2 Kelvin could be achieved. [ABSTRACT FROM AUTHOR]

The European Union intends to reduce the energy consumption in the building sector. The European Directive 2010/31/EU requires the definition of national standards for nearly zero energy buildings. This article presents a research study supported as part of the research initiative 'Zukunft Bau' of the Federal Ministry for the Environment, Nature Conservation, Building and Nuclear Safety for the definition of a nearly zero energy building standard for new buildings in Germany. First, the methodology is discussed, then the first results of a variant study on a model building are presented and discussed. [ABSTRACT FROM AUTHOR]

Energiesparendes Bauen erfordert zusätzlich zu einem hohen Wärmeschutz der Gebäude eine hohe Luftdichtheit der Gebäudehülle. Leckagen in Außenbauteilen sind aus diesem Grund und aufgrund der Tatsache, dass sie Ursache für feuchtebedingte Bauschäden sein können, zu vermeiden bzw. zu beheben. Zur Detektion von Leckagen können Thermografiebilder verwendet werden, die bisher jedoch nur eine lokale Ortung und keine Spezifikation des Energieverlusts durch die Leckage erlauben. Ziel der hier vorgestellten Analyse war es, das Potenzial der Thermografie hinsichtlich eines einfachen, schnellen und präzisen Verfahrens zur quantitativen Bestimmung des Energieverlusts infolge der Luftströmung durch eine Leckage abzuschätzen. Dazu wurde ein Versuchsstand entwickelt und experimentelle Untersuchungen wurden durchgeführt. Diese wurden mit numerischen Strömungssimulationen verglichen, wobei eine sehr gute Übereinstimmung zwischen Experiment und Simulation festgestellt wurde. Darüber hinaus konnte gezeigt werden, dass das Thermografiebild hoch sensitiv ist bezüglich der Strömungsgeschwindigkeit und der bauphysikalischen Kenngrößen des Baustoffs, der die Leckage besitzt. Dies zeigt, dass großes Potenzial darin besteht, aus dem Thermografiebild einer durchströmten Leckage Rückschlüsse auf den Energieverlust durch die Leckage ziehen zu können. Combining thermal imaging with computational fluid dynamics to determine the volume flow through leakages. Energy-saving building requires in addition to a good thermal building insulation an airtight building envelope. Leakages in exterior building elements therefore have to be avoided or repaired, also in consideration of the fact that they can lead to structural damage by moisture. Thermal imaging can be used to detect leakages. However, to date only the positioning of the leakage is possible, while the energy loss through the leakage cannot be specified yet. The aim of the analysis at hand was to assess the potential of thermal imaging regarding a simple, fast and precise method to determine the quantity of the energy loss due to the air flow through a leakage. For this purpose an experimental setup was developed and experiments were conducted. Those were compared to results from computational fluid dynamics. In doing so, a very good agreement between experiment and simulation was found. Furthermore, it could be shown that the thermographic image is highly sensitive to the fluid velocity and the structural-physical parameters of the building material which exhibits the leakage. This demonstrates great potential for drawing conclusions from a thermal image of a leakage with an air flow about the energy loss through this leakage. [ABSTRACT FROM AUTHOR]