The objectives of thisinvestigation were to examine the dynamic water vapour sorption offurnishing materials and to compare the experimental results withpredictions obtained from the Moisture Admittance Model. Dynamic sorption measurementswere carried out for common building materials. The measurements were made by placingspecimens of the materials in a humidity chamber and varying the ambient humidity between46% and 90% RH at constant 22C. The weight of the specimens was monitored in situduring this procedure.
There is a growing demand for buildings to have a high indoor air quality environment. Twoof the main elements that contribute to this quality are temperature and air distribution withinthe occupied space. In modern office buildings particularly in hot climates, care must be takento design the most economical air distribution system that provides comfort for the occupants.There are many techniques available to predict the air distribution patterns in the space atdesign stage, but these are often not very accurate.
Few detailed comparisons of modeled ad measured pollutant concentrations in multizonebuildings have been published. The COMIS air flow and contaminant transport modelpermits simulation of the effects of building and HVAC operation, as well as the influence ofthe local meteorology, on air flows within the building. We have recently used this model tosimulate the release of a gas-phase tracer in a three-story, multi-room building located atDugway Proving Ground, Utah, USA.
There are often tradeoffs among improving IAQ (Indoor Air Quality), maintaining thethermal comfort, and reducing energy consumption for HVAC (Heating, Ventilating, and Air-Conditioning) systems. A prediction model that can simultaneously treat these factors isrequired to realize good design of sustainable buildings. For this paper, a concept of OccupantContaminant Inhalation is used for long-term assessment of IAQ. A long-term evaluationindicator for other factors such as air temperature is also introduced (Occupancy-weightedAccumulated Deviation from thresholds).
With increasing demand for acceptable indoor environment it is necessary, already in theconstruction phase, to estimate what effect different environmental factors have on theoccupants. Thermal sensation is affected by many factors of the indoor environment.Predictive models are available which describe overall thermal sensation as function of themost important factors. In this work reference environments have been investigated with athermal manikin. The results from these measurements are then compared to CFDpredictions.
Results are presented from a study of the performance of fuzzy, rule-based algorithms for thecontrol of indoor air quality through combined control of natural and forced ventilationstrategies, whilst simultaneously meeting thermal and visual comfort requirements as part of aglobal control strategy aimed at optimizing the indoor environment with minimum energyconsumption.
Parametric studies have often been used for sensitivity analyses in the field of the pharmaceuticaland agricultural sector. All such studies aims at bringing some kind of order out of complicatedrelationships between influencing factors and some response parameter(s). With experimentaldesigns and statistical analysis methods, it is possible to trace and quantify influencesof individual as well as combinations of input factors on the response parameter. Thisprocedure has so far very seldom been used within the building sector.
New thermodynamic energy "water potential" based on the chemical potential of a component of mixture gases is defined as the driving force of gaseous phase water flux. Adhesive power, which is a kind of stress call "capillary attraction" and a part of the water potential, is proved as the driving force of liquid phase water flux. Then numerical model of coupled heat and water transfer using the water potential is introduced and influences of stress such as gravity and stationary pressure on water flux are clarified from the viewpoint of thermodynamics.
In this paper, analysis of the ventilation requirements of enclosed vehicular parking facilities is discussed. First, a compilation of existing U.S. and international standards and codes pertinent to the ventilation of enclosed parking facilities is presented. Then, the results of a field testing study are summarised to determine the actual ventilation rates and the contaminant levels in seven U. S. enclosed parking garages. Finally, this paper presents a new design method that provides the minimum ventilation rate requirements for enclosed parking facilities.
In this paper, a zonal model used to predict the air movement, temperature distribution and airquality in a room is presented. It is based on a rough partitioning of the room: it is anintermediate approach between one-node models (that consider an homogeneous temperaturein each room, and, for that reason, do not permit to predict the thermal comfort in a room) andCFD models (that require great amount of simulation time). Where plumes, jets or thermallayers occur, air flow is described by empirical laws.
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