The aim of this research is to apply dynamic Large Eddy Simulation (LES) to predicting the complex turbulent flow field in an air-conditioned room. LES is a method to calculate turbulent flows where only the small-scale (subgrid-scale) motions are modelled and the large-scale (grid-scale) motions are computed directly. Recently, a dynamic subgrid-scale model has been developed that can evaluate a model coefficient dynamically. This paper presents a numerical simulation of LES with a dynamic mixed subgrid-scale model of a flow field in an air-conditioned room model.

The purpose of this study was to evaluate the indoor air quality parameters in a residentialdwelling using information from the field. The subject was a typical example of the modernItalian dwelling stock, built in the 1980s in a residential area in the northernpart of Rome.The dwelling was constructed from pre-cast panels using industrial building techniques. Thewindows were steel-framed and painted. Airtightness was measured to obtain the ACH (airchanges per hour) at 50 Pa pressure difference, and ELA (equivalent leakage area).

The paper presents results from the numerical modelling of the flow field in an existing ventilated office room. The numerical procedure is based on the 3D Reynolds equations closed by the k-e turbulence model and an equation for temperature solved by the finite volume method. The boundary conditions are set in accordance to detailed measurements of the velocity distribution in the air supply diffuser. The established complex flow conditions in the room, which are due to the presence of furniture and buoyancy forces, are presented.

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.

In order to evaluate the impact on indoor air quality of different installation and ventilation strategies, the modelling of indoor air pollutant transfer has been developed in the CLIM2000 software (thermal and airflow code). Then, these models have been used to simulate the evolution of indoor air pollution in an office building floor for a week in winter under different ventilation strategies. The selected pollutants are CO2, CO, NO2 and HCHO and the sources are outdoor pollution for all pollutants and occupancy for CO2. So far, humidity has not been taken into account.

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.

The main objective of this study was to determine the ventilation demand for a gymnasium inthe primary school based on verified metabolic rate.Norwegian guidelines recommend 6.0met as the activity level to be used when calculating the outdoor air flow rate in a gymnasium.Younger pupils have a lower body mass and metabolic capacity than adults, and their demandfor ventilation is therefore lower. The metabolic rate has been assessed by measuring thepupils emission of the dominating bioeffluent CO2 during intensive gymnastic activity.

A secondary analysis of the Dutch prevalence study by Zweers et al shows that office buildingswithout artificial cooling and with operable windows have a lower risk for health symptoms andcomfort complaints than office buildings with artificial cooling and sealed windows. Temperature ,simulations of various office buildings show that in the Dutch climate zone thermal comfortduring summer conditions is secured without the use of artificial cooling if a number of essentialdesign criteria are met.

The air quality in a subway-train was studied to suggest optimal design criteria and operationconditions based on the ventilation demand by passengers. The C02 emitted from thepassengers was the tracer for this study. The C02 bioeffluent from a human body was firstlyquantified and used for the data analysis. Then the C02 concentration was monitored in asubway-train being operated.

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.