Global Information Systems (GIS) are being used to provide data on a wide range of environmental issues, and in the area of climate studies they are being used to determine zones of towns and cities where there are good or poor external environments. From this analysis, planning guidelines can be drawn up to ensure that developments either enhance or do not deter from the environmental quality of the surrounding area.
A Moisture Admittance Model, which takes into account absorption and desorption, has been developed to simulate moisture behaviour in dwellings. The model has been integrated with the BREEZE computer model used to simulate air and contaminant flow. Simulations from the combined model have been compared with predictions using the Louden model and with measurements of vapour pressure taken in a test house. The Louden model tended to over-predict experimental values but there was reasonable agreement between the MAM-BREEZE model results and measured values.
The aim of this work is to investigate turbulent air flows, through measurements inside railway coaches employed for the transport of sick persons. In this kind of environment, assuring occupant comfort and eliminating potentially annoying draught is necessary for safeguarding patients inside the train. As it is known, air velocity is not uniform but, instead, it fluctuates. It is these fluctuations that are the origin of local discomfort. This can result in a draught, which is defined as a local undesired cooling of the body.
This paper examines the impact on domestic background air infiltration of replacing ‘old windows’ with modern double-glazed and draught sealed windows, both with and without controllable ventilation (e.g. trickle ventilators). Methods of estimating the change in infiltration rate produced by such a window replacement are reviewed. A simple model has been developed which, using laboratory measurements of window air permeability, predicts the reduction in infiltration that can be expected when a given number of windows are replaced in a dwelling.
The ventilated ceiling is a flexible solution for kitchen ventilation where heat loads are relatively low and aesthetics is a concern. By using a capture jet in the ventilated ceiling, it is possible to improve the total effectiveness of the ventilation system. This means better indoor air quality and thermal comfort. In addition, the energy consumption of a capture jet ceiling is lower than that of a traditional ceiling concept.
This annotated bibliography reviews current ventilation codes and standards for residential buildings in Europe and North America. It also examines the literature related to these standards such as occupant surveys of attitudes and behavior related to ventilation, and research papers that form the technical basis of the ventilation requirements in the standards.
Natural ventilation, which may provide occupants with good indoor air quality and a high level of thermal comfort, and reduce energy costs, has become an important sustainable strategy in building designs. This investigation used three computational fluid dynamics (CFD) models: steady Reynolds averaged Navier-Stokes equation (RANS) modelling, unsteady RANS modelling, and large eddy simulation (LES) to study both wind-driven and buoyancy-driven natural ventilation.
Passive stack ventilation systems have been used for a number of years throughout the world. They were specifically mentioned within the 1995 revision of the Building Regulations for England and Wales as a means of compliance. BRE Information Paper 13/94 gives recommendations for the design of duct systems within dwellings that place restrictions upon the number and severity of bends that may be used. These restrictions limit the scope for the use of passive stack ventilation within dwellings.
Submitted by Maria.Kapsalaki on Sat, 07/06/2013 - 16:12
Airflow measurement techniques are necessary to determine the most basic of indoor air quality questions: "Is there enough fresh air to provide a healthy environment for the occupants of the building?" This paper outlines airflow measurement techniques, but it does not make recommendations for techniques that should be used. The airflows that will be discussed are those within a room or zone, those between rooms or zones, such as through doorways (open or closed) or passive vents, those between the building and outdoors, and those through mechanical air distribution systems.
This paper presents an overview of systems that utilise thermal mass in conjunction with night ventilation. It discusses the concepts behind and development of a system (CoolDeck) to improve the performance of systems where air is ventilated through false ceiling and floor voids to access hidden mass. The system improves thermal interaction between the circulating air and the thermal mass of the slab. A case study is presented demonstrating the effectiveness of the system in a refurbishment application (Stevenage Borough Council (UK) offices).