Gas phase filters were installed within the air handling unit of a HVAC system feeding 100 % fresh(outdoor) air to an office building. The filter efficiency for ozone (O3) and nitrogen oxides (NO2 and NO) was measured continuously over a one year period as a function of time (filter's life) and outdoor air parameters (temperature and relative humidity). The results show that the filter efficiency varies with time and depends on the temperature and relative humidity of air.

Recent studies have demonstrated the influence that air jets in rooms ventilated by chilled beams have on draught-related thermal sensation. The most critical zone in which people often suffer draught sensation is located near a wall and close to the floor. To avoid the draught sensation, the critical velocities of the returning air jet should be specified and determined before the jet enters the occupied zone. In this study, the velocity of the attached plane jet was modelled and measured at six heights and at eight different distances from the wall.

The natural ventilation of a building, flanked by others forming urban canyons and driven by the combined forces of wind and thermal buoyancy, has been studied experimentally at small scale. The aim was to improve our understanding of the effect of the urban canyon geometry on passive building ventilation. The steady ventilation of an isolated building was observed to change dramatically, both in terms of the thermal stratification and airflow rate, when placed within the confines of urban canyons.

In the case of cross ventilation through a large opening, it is well known that the inflow direction at the opening is not normal to the opening. A simplified prediction method for simultaneously predicting the inflow direction at the inlet opening and the airflow rate is presented. It is also well known that the use of general discharge coefficient values (CD) is not suitable for the calculation of cross ventilation rate. The first reason is that the simple connection of the pressure loss coefficient of an opening (?

Wind approaching a building provided with openings on the windward and leeward sides has a choice, either it flows through the openings or flows around and above the building. This choice gives rise to a dominant stream tube containing the fluid flowing through the openings. In this paper the stream tube is analysed based on wind tunnel measurements and CFD simulation. A house model with dimensions 120 mm (Width)120 mm (Height)180 mm (Length) was provided with rectangular openings of equal size located opposite each other. The end walls were thin giving rise to a sharp edged opening.

This paper presents the preliminary findings from the first stage of a physical survey and modelling case study conducted to obtain modelled and actual energy consumption profiles for a UK multi-storey mixed use educational building (the Bute building at the University of Wales, Cardiff).

Full-scale experimental and computational fluid dynamics (CFD) methods were used to investigate the velocity and temperature fields in a mechanically ventilated room. Detailed airflow fields were measured in three cases of ventilation air temperature: an isothermal case, a hot case and a cold case. The ventilation system created a round jet which developed near the ceiling. The experimental data were used to test two turbulence models: a first order k-e turbulence model and a second order RSM turbulence model.

Internal pressure coefficients in a building with wind-driven cross-ventilation caused by sliding window openings on two adjacent walls are presented and compared with previous works. The study found that internal pressure coefficients vary considerably with the opening area (or wall porosity) and the inlet to outlet ratio. The internal pressure is not uniform in a building with cross-ventilation, particularly for large openings (wall porosity higher than 10%). For inflow calculation, the average internal pressure coefficient should be used as an input in the orifice equation.

A number of methods have been used to quantify the cooling effects of air movement on the human body. For simplicity these methods limit the number of variables influencing the effect. A new method using the difference in Standard Effective Temperature (SET*) values between a condition with 29.5 fpm (0.15 m/s) and the proposed elevated air speed allows all the relevant variables (i.e. air temperature, mean radiant temperature, air speed, humidity, metabolic rate, and clothing insulation) to be taken into account. Cooling effect of air movement is normally based on uniform velocity airflow.

This paper is not a technical paper but, instead, focuses on the methods by which information on recent advances in ventilation technology and systems may be transferred to engineers. This is important because it enables the application of these innovations in the design and maintenance of buildings. In this context, the paper describes the educational material developed by the European project Vent DisCourse. It consists of material specifically written to facilitate distance learning postgraduate study in the area of energy efficient ventilation for buildings.