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This investigation of the window opening data from extensive field surveys in UK office buildings demonstrates: 1) how people control the indoor environment by opening windows;2) the cooling potential of opening windows; and 3) the use of an 'adaptive algorithm' for predicting window opening behaviour for thermal simulation in ESP-r. It was found that when the window was open the mean indoor and outdoor temperatures were higher than when closed, but show that nonetheless there was a useful cooling effect from opening a window.The adaptive algorithm for window opening behaviour was then used in thermal simulation studies for some typical office designs. The thermal simulation results were in general agreement with the findings of the field surveys. The adaptive algorithm is shown to provide insights not available using non adaptive simulation methods and can assist in achieving more comfortable, lower energy buildings while avoiding overheating.

This version is available at https://strathprints.strath.ac.uk/13856/ Strathprints is designed to allow users to access the research output of the University of Strathclyde. Unless otherwise explicitly stated on the manuscript, Copyright © and Moral Rights for the papers on this site are retained by the individual authors and/or other copyright owners. Please check the manuscript for details of any other licences that may have been applied. You may not engage in further distribution of the material for any profitmaking activities or any commercial gain. You may freely distribute both the url (https://strathprints.strath.ac.uk/) and the content of this paper for research or private study, educational, or not-for-profit purposes without prior permission or charge.Any correspondence concerning this service should be sent to the Strathprints administrator: strathprints@strath.ac.ukThe Strathprints institutional repository (https://strathprints.strath.ac.uk) is a digital archive of University of Strathclyde research outputs. It has been developed to disseminate open access research outputs, expose data about those outputs, and enable the management and persistent access to Strathclyde's intellectual output.1 Title:Thermal performance of a naturally ventilated building using a combined algorithm of probabilistic occupant behaviour and deterministic heat and mass balance models Authors:Geun Abstract:Natural ventilation is an established passive cooling technique with the potential to reduce building energy demands through the avoidance of air conditioning. However there has been uncertainty about the potential of natural ventilation in practice due to a lack of knowledge about the occupant interactions with windows for any given situation. This study explores the role of occupant behaviour in relation to natural ventilation and its effects on the summer thermal performance of naturally ventilated buildings. A behavioural algorithm is developed (the Yun algorithm) representing probabilistic occupant behaviour and implemented within a dynamic simulation tool. A core of this algorithm is the use of Markov chain and Monte Carlo 2 methods in order to integrate probabilistic window use models into dynamic energy simulation procedures.The comparison between predicted and monitored window use patterns shows good agreement.Performance of the Yun algorithm is demonstrated for active, medium and passive window users and a range of office constructions. Results show for example, that in some cases, the temperature of an office occupied by the active window user in summer is up to 2.6C lower than that for the passive window user.A comparison is made with results from an alternative behavioural algorithm developed by Humphreys . In general, the two algorithms lead to similar predicted results, but the results suggest that the Yun algorithm better reflects the observed time of day effects on window use (i.e. the increased probability of action being taken on arrival).

Using a detailed building simulation model, the amount of thermal buffering, with and without phase change material (PCM), needed to time-shift an air source heat pump's operation to off-peak periods, as defined by the UK 'Economy 10' tariff, was investigated for a typical UK detached dwelling. The performance of the buffered system was compared to the case with no load shifting and with no thermal buffering. Additionally, the load shifting of a population of buffered heat pumps to off-peak periods was simulated and the resulting change in the peak demand on the electricity network was assessed. The results from this study indicate that 1000 L of hot water buffering or 500 L of PCM-enhanced hot water buffering was required to move the operation of the heat pump fully to off-peak periods, without adversely affecting the provision of space heating and hot water for the end user. The work also highlights that buffering and load shifting increased the heat pump's electrical demand by over 60% leading to increased cost to the end user and increased CO2 emissions (depending on the electricity tariff applied and time varying CO2 intensity of the electricity generation mix, respectively). The study also highlights that the load-shifting of populations of buffered heat pumps wholly to off-peak periods using crude instruments such as tariffs increased the peak loading on the electrical network by over 50% rather than reducing it and that careful consideration is needed as to how the load shifting of a group of heat pumps is orchestrated

A theoretical model of the interaction between a building and its occupants is developed based on field survey data; the role of the model in building performance simulation is illustrated. If free to do so, people adjust their clothing or available building controls (windows, blinds, doors, fans, and thermostats) with the aim of achieving or restoring comfort and reducing discomfort. Initially responses to thermal conditions are considered. Trigger temperatures are established where responses to warm or cold thermal discomfort may occur. These trigger-temperatures depend on (among other things) clothing (which may depend on season and social conditions) and air movement (e.g., fan setting). Trigger-temperatures differ from person to person and from time to time. If several controls are available people will use those that are most user-friendly, effective and free from undesirable consequences, and this is represented in the model by a constraint assigned to each control option. The concept of constraints is then expanded to capture non-thermal stimuli for control use (e.g., fresh-air). Using datasets from surveys in Europe and Pakistan, estimates are made of the parameters used in the model: the comfort temperature in relation to the prevailing outdoor temperature, the extent of inter-personal variation of trigger temperature, the effect of a fan on the comfort temperature, and the values of constraints that affect the use of windows and fans in the surveyed buildings. The incorporation of the new model, including constraints, into building simulation code is illustrated. Some limitations or unknowns in the current model are identified and possible approaches for future research to fill these gaps suggested. The application of the model in building performance analysis and building design is discussed