To evaluate wind pressure distribution on a building by using CFD (computational fluid dynamics), it has been general practice to use k-e models. However, it is known that the use of the standard k-e model has disadvantages such as overestimation of wind pressure coefficient and turbulent kinetic energy on the windward surface where wind impinges on the building. To overcome these problems, various modifications of the k-e model have been proposed.

This paper addresses the applicability of passive and low energy cooling technologies in the Czech Republic. The main research methods are climate analysis and buildings and systems analysis, both with the objective to assess the building performance potential of passive and low energy cooling technologies. The analysis is based on case studies, which include building performance simulation as well as in-situ monitoring. The role of computer simulation in low energy building design and optimisation is briefly discussed.

Sustainable architecture design for tropical climates requires the use of natural ventilation combined with other strategies including: the use of appropriate materials, site location, orientation of faades and solar shading, etc. Requirements for thermal performance and indoor thermal comfort also depend on the geographical site where the building is located. The new Brazilian standard Norma ABNT NBR 15220-3 has established seven bioclimatic zones and some architectural guidelines for low-income houses.

In this study, the evaluation of cross ventilation is presented based on the simultaneous analysis of inside and outside conditions and for wind directions other than 0 degrees (i.e. for wind flow that is not aimed directly or normally to the inflow opening). The first part of the paper considers a conventional CFD analysis and compares the performance of the widely used k-e turbulence model as well as the modified Durbin k-e turbulence model. While a CFD approach can give good results it is very labour and computationally demanding.

This paper reports the findings of a field study and telephone survey into the impact of window replacement on air infiltration and moisture problems in UK dwellings. The results of a telephone survey of 250 UK houses suggested that the installation of tight, well sealed replacement windows does not appear to be causing a significant increase in IAQ problems as perceived by the occupants. After having windows replaced only 2% of respondents (5 households) reported worse problems with condensation and only 1% (3 households) reported worse problems with mould.

It is difficult to design a naturally ventilated indoor environment because there is insufficient knowledge to evaluate the effect of the natural ventilation space quantitatively. Especially, natural ventilation rate is not yet fully understood. In this paper, the properties of natural ventilation with large openings are examined mainly from the results of measuring ventilation rate.

Cross ventilation to reduce cooling energy is one of the most important techniques for maintaining acomfortable indoor environment in hot and mild seasons. However, at present, it is difficult to design the indoor environment under cross ventilation because there is insufficient knowledge to evaluate the effect of cross ventilation quantitatively.

The aim of the work was to investigate the effect of upstream geometry of the nozzle on the turbulence mixing and temperature distribution in still air large enclosed spaces. Prototype experiments were carried out with the JETs (Jet Environmental Techniques) existing nozzle geometry in a test room. These were used to validate, under steady state conditions, the application of an RNG kappa-epsilon turbulence model. In the next stage a range of nozzle profiles of similar inlet and contraction diameters were tested under identical conditions similar to the prototype test room.

The assessment of building thermal comfort quality in the Mediterranean context necessitates an accurate knowledge of air temperature and velocity fields inside the space. Also, these thermal and airflow aspects must be considered in combination because of their very strong interdependence. In this particular context, a three-dimensional calculation model of coupled heat transfer and airflow calculation has been developed, which enables the evaluation of temperature field and airflow pattern inside unconditioned buildings under transient conditions, taking into account external conditions.

The present study investigates the effect of alteration in the building shape due to some common remodelling practice on the wind pressure differences delta-p for cross-ventilation of a semi-detached low-rise building using Computational Fluid Dynamics (CFD). A commercial code ANSYS CFX was employed to solve the flow governing equations. The standard k-e, renormalisation group (RNG) k-e and Shear Stress Transport (SST) turbulent models were adopted for comparison and the computed velocity was validated against full-scale measurement data.