Daylight is an energy efficient solution for illumination and visual comfort in buildings. However, successful daylight design requires effective daylight control technology to eliminate the negative impact such as overheating, unbalanced indoor daylight distribution and glare. With this mind, the current thesis presents a novel multifunctional roof panel which might be applied in atrium and large green house. The working principle of the panel is based on the non-imaging low-concentration solar collector: dielectric Compound Parabolic Concentrator (CPC). Detailed study on the dielectric CPC has found that there would be some light escaping from side wall of CPC when the incident light is beyond CPC acceptance angle, which could actually be used for indoor daylight provision; while the incident light concentrated on the base of CPC could be used for concentrating PV application. Thus a dielectric CPC panel which consists of several trough dielectric CPC rods is designed and manufactured, its function of hybrid PV/Daylight is investigated through PHOTOPIA simulation and outdoor testing, both simulated and measured results showed that under sunny condition, only 10-15% of light could be transmitted through the panel in cooling season, and the rest of the light is used for concentrating PV application; while light transmittance of about 40-60% is achievable in winter period, when daylight is desired. Additionally, constant light transmittance of about 40% is achievable under overcast sky. The above figures could verify the seasonal daylight control ability of the panel. On the other hand, for the designed panel, the rejected heat on PV could still flow into the building. As a result, a PV/Thermal system is designed to remove the rejected heat on PV cell and reutilize it for thermal application such as food drying. The design parameter such as approach velocity, pitch distance, and perforation porosity are numerically investigated by CFD simulation. The prototype of the system is built and measured under solar simulator and real sky. Both simulated and measurement results showed that the heat recovery efficiency could be 40-80% depending on different geometries and approach velocities; and little amount of rejected heat could transfer from the PV cell to the building interior. The hybrid PV/Thermal application seems to be achievable. Lastly, the energy and economic performance for the EW-orientated dielectric CPC panel is investigated using new proposed concept of “inner south projection angle” and its correlation with the CPC optical performance, the building energy simulation software EnergyPlus and its weather data are also employed. An example case on an educational building with a central atrium in Nottingham shows that: compared to the conventional double glazing window, there is 55% increase in useful daylight illuminance (500-2000lux) percentage; 81.5% reduction in window solar heat gain in cooling season and only 10.78% reduction in window solar heat gain in heating season; there is also a power generation of 290.65W/m2 from PV cells; and the estimated payback period is less than 5 years. Therefore, the proposed multifunctional roof panel for PV/Thermal/Daylight application could comprehensively utilise the solar energy and provide comfort thermal and visual indoor environment.

A lot of research has been conducted in the past decades on urban heat island (UHI) all over the world. Nevertheless, the UHI effect has not been included in weather data used by building services engineers to design buildings and size their heating and cooling plants. This research was carried out to investigate the UHI effect in Greater Manchester by setting up fixed point monitoring stations over the city. Woodford Met Office ground observation station was selected to be the rural reference point. A multiple regression model was developed to incorporate the heat island effect into the Manchester weather data for engineering usage.It was found that the urban heat island intensity (the difference between the rural and urban area temperatures) can be as high as 8°C in summer and 10°C in winter in Manchester. Clear and calm nocturnal temperature data was used (when maximum heat island occurs ) to find the relationship between the UHI intensity and sky view factor (SVF), distance away from the city centre, evapotranspiration fraction (EF), wind speed, cloud cover and rural reference temperature. Results indicate that all factors have a negative linear relationship with UHI intensity. All measured data were fed into a statistical software package to create general linear regression models. Validation showed that these models were capable of predicting average UHI effect to a good accuracy. The maximum heat island effect peaks are not so accurate. However, an analytical model was developed based on energy balance equations to predict the maximum heat island effect. Validation shows a good prediction for summer but not so good for winter. This is probably due to the lower average UHI intensity in winter than in summer.

Though heating, insulation, wall claddings and cavity-wall construction are considered as measures for remediating moisture and condensation in buildings, ventilation of wall cavities has however become a mantra among architects and other building professionals. Holes of any size and shape are made and located on building facades based on the accepted wisdom that a little air movement will keep the wall cavities dry. Whilst ventilation has been found to be successful in the control of moisture and condensation in rooms and larger enclosures, there is however insufficient understanding of how it works in thin spaces with high aspect ratios, such as the wall cavities studied in this thesis.In order to put in place good control and management practices in the remediation of moisture and condensation in vertical wall cavities by natural ventilation, it is vital to understand the dynamics of airflow in these cavities. In this thesis therefore, different size and shape of slots were employed to numerically investigate the effects of size, spacing and number of the slots on the characteristics of the velocity fields (patterns of airflow and distributions of velocity) in different cavity models. The Reynolds-Averaged-Navier-Stokes (RANS) methodology was employed to simulate the cavity flows under different modelling conditions using FLUENT. The BS 5925 model, an empirical relation for predicting ventilation rates in rooms and other larger enclosures, was employed and modified to predict ventilation rates in these cavities. Experimentally, the mapping of the airstreams in these cavities was obtained under similar reference (inlet) wind speeds employed for the numerical investigations.The results of this study show that there exists a potential at higher wind speeds for natural ventilation in the remediation of moisture and condensation in the cavities of vertical walls. The steady state approach employed in the RANS-based computation of cavity flows in this thesis averages out the peak values of air velocities and therefore gives no information about regions of maxima or minima velocity values even at higher wind speeds. This makes the predicted air change rates insensitive to the inlet air velocities from the ventilation slots and therefore makes the results more applicable for long term control and management of moisture in these cavities. In order to therefore put in place short, medium and long term plans for remediation of moisture in these wall cavities, a time-dependent computation is required. This will also allow the efficiency of the cavity ventilation to be properly assessed. Using the modified BS 5925 model, reasonable predictions were obtained for the air change rates of the wall cavities with the different size of ventilation slots employed. Close agreements are also obtained at lower and higher wind speeds between the predicted ventilation rates from the modified BS 5925 model and the experimental results employed as benchmark for validating the results.

Diese Arbeit untersucht lastabtragende Klebungen unter ständiger Beanspruchung durch flüssige Medien und bewertet deren Potenzial für den konstruktiven Glasbau. Im Vordergrund steht zunächst die Frage, wie sich Klebverbindungen in ständiger Flüssigkeit verhalten. Welchen Einfluss haben statische und dynamische Beanspruchungen auf die Verbundeigenschaften? Und wie wirken sich unterschiedliche Lasteinwirkungsdauern aus? Ausgehend von diesen zentralen Fragestellungen wird ein umfangreiches Prüfprogramm mit zugehörigem Bewertungskonzept entwickelt und an zehn ausgewählten Klebstoffen angewendet. Experimentelle Kleinteilprüfungen bestimmen die mechanischen Kennwerte des reinen Klebstoffs nach Lagerung in flüssigen Medien. Weiterführend analysieren Verbundprüfungen den Einfluss flüssiger Medien auf die Verbundeigenschaften der Klebverbindung zum Fügepartner Glas. Das Prüfprogramm beinhaltet zudem kombinierte Prüfungen aus Wasserlagerung mit mechanischer Zug-Schwellbeanspruchung sowie Wasserlagerung mit gleichzeitiger Dauerbeanspruchung. Die gewonnenen Ergebnisse werden direkt auf das Referenzbeispiel eines plattenförmigen Photobioreaktors angewendet. Dieses Glaselement dient zur Kultivierung von Mikroalgen und ist zentraler Bestandteil einer neuartigen Bioenergiefassade. Im Inneren des Photobioreaktors befinden sich lastabtragende Klebverbindungen, die ständig dem flüssigen Kulturmedium ausgesetzt sind. Zwei dieser plattenförmigen Photobioreaktoren mit einer Höhe von 3,00 m werden realisiert und ihr Verhalten in verschiedenen Lastzuständen analysiert. Für die lastabtragenden Verklebungen im Innenraum wird der Vorzugsklebstoff aus den Kleinteilprüfungen verwendet. Die gesamte experimentelle Versuchsdurchführung begleiten numerische Simulationen. Die Arbeit liefert einen Beitrag zu lastabtragenden Klebver-bindungen mit ständiger Beanspruchung durch Flüssigkeiten. Die Ergebnisse aus Kleinteilprüfungen werden an einem Referenzbeispiel des konstruktiven Glasbaus praktisch umgesetzt und in Bauteilversuchen überprüft. Die gewonnenen Erkenntnisse lassen sich auf andere Glaskonstruktionen mit kurzzeitig und dauerhaft flüssigen Beanspruchungen übertragen.:1 Einleitung 2 Bioenergiefassaden 3 Beanspruchungsanalyse 4 Versuchsplanung 5 Kleinteilprüfungen 6 Bauteilprüfungen 7 Berechnung und Dimensionierung 8 Diskussion 9 Zusammenfassung und Ausblick 10 Literatur / This doctoral thesis analyses load-bearing adhesives in glass constructions which are permanently immersed in fluid environments. In particular, the study focuses on the following key questions: How do structural adhesives behave during permanent fluid immersion? Does the failure mode during fluid exposition differ between static and dynamic load situations? And what are the effects of short- and long-term load durations on adhesive properties? In order to answer the stated research questions, experimental studies are executed. Additional numerical simulations accompany the entire test program. The paper distinguishes experimental studies on small-scale specimens and full-scale specimens. Initial tensile tests on small-scale specimens analyse the mechanical properties and their sensitivity towards ageing mediums. The test series evaluates the adhesive properties to glass under the influence of am-bient temperatures and liquid ageing mediums like water, base and acid solution as well as hydroxide peroxide solution. The small-scale tests also consider long-term creep tests and mechanical-cycle loading. The gathered results are evaluated against a set of selection criteria to identify the most suitable adhesive system out of the range of initially ten tested adhesive systems. Finally, the preferred adhesive system is applied on a full-scale reference example, which is a flat plate photobioreactor. Two photobioreactor panels with a height of 3,00 m are assembled and tested. The panel is part of a bioenergy facade that cultivates microalgae in the building skin. In general, the photobioreactor panel resembles an insulating glass unit. Deviating from conventional glazing systems its front and back glass panes are joint by inner structural adhesives. Since the panel is filled with algae medium its adhesive connections are immersed in liquid algae medium. In summary, the doctoral thesis deepens the current knowledge on adhesives in glass constructions under permanent fluid exposition. Research findings are applied on two operating photobioreactors made of glass. And finally, the gained results are promising for future glass construc-tions facing permanent fluid exposition.:1 Einleitung 2 Bioenergiefassaden 3 Beanspruchungsanalyse 4 Versuchsplanung 5 Kleinteilprüfungen 6 Bauteilprüfungen 7 Berechnung und Dimensionierung 8 Diskussion 9 Zusammenfassung und Ausblick 10 Literatur

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