Evaluating the impact of Ventilation strategy and Window Opening Area on Overheating Issues

Sustainable Built Environment Conference 2019 Tokyo Built Environment in an era of climate change: how can cities and buildings adapt?

生态环境科学

Jimenez-Bescos, C.^1

Architecture and Built Environment, University of Nottingham, United Kingdom^1

关键词: Building simulation model;    Cross ventilation;    Energy in buildings;    Natural ventilation;    Night ventilation;    Reducing energy consumption;    Ventilation strategy;    Window openings;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/294/1/012042/pdf
DOI  :  10.1088/1755-1315/294/1/012042

学科分类：环境科学（综合）

来源: IOP

【 摘 要 】

Thermal mass has the benefit of regulating energy in buildings and generates potential savings in energy and CO2 emissions. The result of the effect of climate change will be more intense and longer periods of summer heat waves. Use of the building thermal mass can reduce overheating in summer and minimise the need for cooling energy, reducing energy consumption and CO2 emissions. Night ventilation is one of the key factors to maximise the benefits of thermal mass in buildings but due to issues in security and pollution, in many situations windows can only be effectively opened during occupied hours. Cross ventilation provides gains versus the use of single side ventilation but it is not always possible to have it. The main aim of this study was to evaluate the influence of window opening area and night ventilation on the thermal mass benefits to overheating by exposing the thermal mass. A second aim was to understand the further benefits that could be obtained by using cross ventilation in reducing overheating This study was based on dynamic thermal simulations to analyse the overheating performance of a test room with covered and exposed thermal mass. The testing room was simulated for a range of window openings from 5% to 40% area opening with single-sided and cross natural ventilation. Fifthteen building simulation models were performed using the Energyplus plugin in DesignBuilder to evaluate the effect on the thermal mass behaviour to mitigate overheating according to different window opening areas during occupied hours in two different natural ventilation conditions. The simulation results show that by exposing and making use of the room thermal mass, the number of hours above 28°C can be reduced with the reduction being proportional to the window opening area. The CIBSE TM52 overheating assessment is only passed by using window opening areas above 20% with a cross ventilation strategy, but they could generate occupants discomfort.