Prediction of indoor gaseous pollutant dispersion by nesting sub-zones within a multizone model

A zonal model has been nested within a multizone model to allow increased resolution in the prediction of local air flow velocities, temperature and concentration distributions between and within rooms. Simulations from the new program have been compared with measurements and results from other models.

Measurements of air temperatures close to a low-velocity diffuser in displacement ventilation using an infrared camera

The authors have developed a whole-field measuring technique that allows the visualization of air temperatures and airflow patterns over a large cross-section. For that measurement, an infrared camera and a measuring screen placed in the airflow are used. Thanks to that technique, real-time images within large areas can be recorded and transient events can be captured. The method was applied to a flow from a low-velocity diffuser in displacement ventilation.

Comparing zonal and CFD model predictions of indoor airflows under mixed convection conditions to experimental data

The present work is part of a research effort aimed at integrating a detailed model of airflow in large spaces with an algebraic multizone infiltration model to describe pollutant transport and coupled air flows within and between complex buildings and large spaces. In the past 15 years, zonal models were developed with the goal to obtain an approximate prediction of airflow characteristics in large indoor spaces. Also, reducing the number of grids in CFD models is a natural way of decreasing their demand of computational resources to solve air flows in room.

Thermo-hydraulic measurements in urban environment

Measurements of wind speed and wind direction, air temperature inside and outside an urbancanyon also infrared radiation in buildings have been measured on summer 2001 in Athens, in fivedifferent urban canyons, in the frame of Urbvent project. Urban canyons with different geometricalcharacteristics and orientation were placed in five different neighborhoods in Athens.Measurements took place in four different height levels inside each canyon, in the facades ofthem, also in the top of each canyon.

Thermal comfort in low-cost dwellings : a case study in Curitiba, Brazil

The main goal of the present study was to determine thermal comfort parameters for dwellers of low-cost houses for a given set of indoor environmental conditions. 112 people living in over 60 dwellings were interviewed, according to a comfort questionnaire where information regarding age, sex, clothing, level of activity, thermal sensation and preference of the subjects was collected. Environmental factors such as air temperature and humidity were simultaneously registered with T/RH data-loggers. Results were then analyzed by comparing subjective and environmental factors.

Local comfort and air quality quantification via integrated building simulation

This paper describes the CFD model implemented within a building simulation program (ESP-r). It gives results examples to demonstrate the application potential of the model to calculate local comfort conditions and air quality.

Operative temperature measured by ellipsoid-shaped sensor

Operative temperature which takes in account air temperature and radiation is of great importance when one defines human comfort.This paper gives information about definition, calculation and measurement of operative temperature.

Flow behaviour in a ventilated room - Measurements and simulations -

Disturbances from the surroundind environment and boundary conditions can influence very much the flow pattern , particles concentration and temperature distribution in a room.This report confirms the importance of working with measurements and simulations in parallel. Simulations of indoor air quality need to be validated . Guidelines on how to combine results are discussed in the paper.

Interferometric modeling of temperature fields in ventilated and heated spaces

The interferometric modeling of temperature fields allows to visualize clearly the distribution of temperatures in typical centres of ventilated and warm air heated spaces and spaces heated using radiators and walls. For the visualization the Mach-Zehnder interferometer is applied and the research is realized on diminished models by means of the similarity theory application.

A zonal model for predicting simultaneous heat and moisture transfer in buildings

A zonal model was developed to predict temperatures and moisture in a room taking into account the adsorption/desorption by building materials. Results show how adsorption/desorption influences the moisture field.