Efficient local air recirculation at ceiling level promote the performance of purifiers and anti-epidemic efficiency of mixing ventilation in a small shared rooms

Rising temperatures due to climate change and the increased Urban Heat Island (UHI) effect both have a major impact on Singapore’s outdoor comfort. Research has reported an average UHI in Singapore of 4°C, which can even exceed 7°C at some times of the day. (Acero & Ruefenacht, 2017) Increasing convective surface heat transfer from the human body by means of induced wind speeds is an important strategy to improve outdoor thermal comfort. However, the combination of its high urban density, leading to a considerable number of obstructions for urban wind flows, and the generally low wind speeds due to its geographical proximity to the equator makes urban ventilation in Singapore challenging. (Acero & Ruefenacht, 2017) Since the 1970s, void decks, open spaces at the ground floor of buildings, have become a typical characteristic of public housing flats in Singapore. These have been shown to potentially increase wind speeds by more than twofold. (Chew & Norford, 2019) However, the effect of void deck geometries on the imbalance between outdoor thermal and pedestrian wind comfort in a realistic urban setting has not been addressed before.
Hence, the main research question of this thesis was formulated as follows: How can the geometry design of void decks be optimized to enhance urban ventilation for outdoor thermal comfort in Singapore while ensuring good pedestrian comfort?  A strong mismatch between pedestrian wind comfort and outdoor thermal comfort was observed in the study area with the simulated monsoon wind conditions. This marks the importance to perform wind microclimate analyses in a tropical environment as Singapore, focusing on both aspects. This work demonstrates a design methodology that combines parametric design tools with CFD (computational fluid dynamics) simulations with the aim to make better wind-informed design decisions for an urban context. 
Using a parametric building model, ten void deck geometry variants were generated and compared. The implications of the observed flow pattern in terms of urban planning were clarified. For example, while a horizontally converging void deck geometry was found to be effective at directing the urban ventilation towards a target location due to the funnel-shaped induced wind speed region downstream, horizontally diverging void decks led to a more evenly spread region of accelerated flow along the void length. The highest amplification factors inside the void deck were obtained for a vertically diverging geometry. This geometry was subsequently applied to all the buildings facing the prevailing wind directions in the study area, Clementi, using a parametric urban model. This model allows the user to apply various void deck geometries to different building groups independently from each other based on their orientation. A comparison of the wind speed and air temperature distributions after the urban-scale intervention to the current situation showed a wind speed increase and temperature decrease in almost all the void decks. While the amplified wind speed region extended downstream of some void decks, other areas in between the buildings showed a slowed down wind flow. The temperature effects were more extreme at the more closely-packed areas with a smaller distance in between the buildings. Overall, it was concluded that the void deck modifications did not only affect the local wind microclimate inside the void decks, but also altered the wind conditions in between the buildings. Ideally, these wind speed-amplifying void decks should be used in combination with other urban cooling strategies. 
The proposed workflow was demonstrated for the geometry design of void decks, but is also applicable in the optimization process of other building features which may affect the urban wind microclimate, such as canopies and building podia.

This project aims to design the integrated control of shading and operable windows for CEG east facade to improve the thermal comfort with respect to energy consumption. The design stage focused on the thermal advantages that the integrated control of shading and operable window brought to the CEG building. The controls are simulated in the EnergyPlus engine with DesignBuilder interface. The output data of temperature distribution and heating demand of the two proposals were used to compare for choosing the best control strategy during the operating stage. One proposal was using the old glazing materials and the other one was replacing the whole facade. After choosing the final solution (new construction), the effectiveness of shading and operable window control, the visual and ventilation performance of the integrated control, the possible energy deviation, the design refinement were conducted. The final control had a total discomfort occurrence of 39.5 hours, heating demand of 36.10kWh/m2 and lighting demand of 11.17kWh/m2. Compared with the simulation of the existing situation with new construction, it reduced 79% of discomfort hours and 38% of heating demand.

Problem Definition and main objective: Current prefabricated building envelope systems utilised for energy reduction renovations are expected to be a long-lasting solution. In practice, the building envelope systems are not adapted to facilitate future updates due to changing regulations or changing standards. Furthermore, in most renovation systems the material or component with the lowest service life dictates the service life of the complete system, leading to materials being disposed of before they reached the end of their potential service life. The goal of the thesis is to design a system that is adapted to these issues by being a flexible system that separates functionalities in separate boxes and layers, and therefore is able to upgrade or replace individual components when necessary to ensure the system’s long-term functionality. Study Design: Literature review, followed by the formulation of a strategy and a design. Design effectiveness is confirmed through application on a case study. Long-term functionality is confirmed through transformation of the case study application based on formulated scenarios. Setting: The thesis is part of a series of ongoing research projects associated with the 2ndSkin project. The case study is an apartment block located at the Soendalaan in Vlaardingen. Results: A design concept for an external building envelope system for energy reduction renovation of Dutch post-war apartments elaborated in a 1 to 5 detail scale. The final design incorporates an adaptable aluminium frame system with module boxes containing different functionalities, which can be slid into the main frame. The system is finished with a clamp system with cladding, functioning as the protecting layer for the system.

Nowadays the use of renewable energy resources is a necessity. Approximately 13% of the energy spent in Greece comes from renewable energy resources, however a significantly higher percentage is essential in order to meet the European standards by 2020. A prompt solution is the in-situ energy generation. Additionally, the harmful emmisions of the various air-conditioning and refridgerating systems need to be eliminated. The current master thesis involves the use of solar energy for indoor temperature regulation, mainly for cooling purposes. This is achieved by the use of two different technologies; the photovoltaics and the thermoelectrics. A series of PV panels convert the solar energy to DC power, which is supplied to the thermoelectric devices. The TE modules are able to create temperature difference and depending on the direction of the DC current, they can function either for cooling or for heating. The system is 100% emission-free and can operate entirely on renewable energy. Location of the project is set to Athens, Greece, a city with rather high air-conditioning demands during summer and high solar irradiation all year long, traits which make it very favorable for a PV-TE solar cooling application. Objective of the thesis is to develop a solar cooling facade concept which, along with the implementation of passive design strategies, is able to cover the cooling and heating demands of a certain office space. Considering the context, the local climate, the prominent vernacular building strategies have been studied. Moreover, a field research and analysis of 25 case study buildings has been carried out leading to the definition of the ‘typical office building’ in Athens. Based on the typical office, a passive optimization with the implementation of multiple passive strategies has been carried out resulting in the optimum scenario. The PV and TE system has been calculated and designed according to the optimum passive scenario and is applied on a case-study building. A range of architectural possibilities is explored, based on the typical office buildings of the area.

The fire safety strategy in hospitals is complex, and requires an integrated approach, because of the presence of vulnerable and reliant patients who need assistance during evacuation. The current regulations in the Netherlands seems to be outdated, and don’t fulfill the current use and the changing design trends. The design trends of hospitals are changing, shifting towards a healing environment with mostly single patient rooms.
Research into the actual disconnecting times of different types of patients is performed, to determine the total evacuation time per patient. As displayed different phases of the evacuation route are gathered and analysed. With these differing evacuation times, the design can be adapted to the required egress time per specific ward. The evacuation times of patients on a Dialysis, Intensive Care, Neonatal ICU, Heart monitoring, Recovery and a standard nursing ward have been gathered.
With an interactive design tool, the actual risk and Required Safe Egress Time calculations can be made. A relative probability calculation indicates the risk of casualties per ward, compared with a design fulfilling the maximum restrictions of the Dutch Building Decree. Together with the gathered data, specific RSET calculations can be made for different types of wards.