A test room was used to evaluate the impact of airflow parameters on the effectiveness of an air cleaning system. The room’s dimensions were nominally 11.2 m x 5.7 m x 2.7 m. The room has a drop-ceiling with space above for installation of above-ceiling air cleaning equipment and routing of ventilation ductwork. The HV AC system supplying the room could be turned on for constant flow (-349 ls·1) or left off to independently evaluate the effectiveness of the air filtration system.
Air temperature, air humidity and ventilation has been measured in a Swedish baroque castle. Results are presented for a measurement campaign comprising four periods under varying climatic conditions. A passive tracer gas method, known as the homogeneous emission technique has been used to measure the ventilation rates and air distribution in the building. As the palace is essentially unheated, wind pressure is the main driving force for ventilation. The air change rate is highly varying and differs considerably in different parts of the building (0.5-1.5 ACH).
This paper describes a numerical method for the determination of the effective depth of fresh air distribution in rooms with single-sided natural ventilation. The numerical method involves predicting air flow and the local mean age of air. The renormalisation group two-equation model of turbulence is used with the conservation equations of mass, momentum and energy to predict turbulent buoyancy-induced room air flow. The local mean age of air is then obtained from the solution of air flow equations together with the transport equation for the age of air.
In order to explain the effect of heat recovery on a passive ventilation system using stack effect, and to show the factors and conditions that the heat-recovery system can be installed in a passive ventilation system, the following investigations are made. The characteristics of the airflow in houses using the passive ventilation with the heat recovery units were investigated from scale model experiments and numerical experiments. And the effect of energy saving by the heat recovery system was investigated from numerical experiments using the standard weather data of cities in Japan.
This study investigates indoor air environment via the flow fields, temperature fields and air contaminants (carbon monoxide) distributions in conventional residential kitchens, and looks for effective methods to solve those problems through natural ventilation techniques. Numerical simulations of the physical problem under consideration have been performed via a finite volume method for solving the governing equations and boundary conditions.
The need to separate impurities from air or other gases has increased as regards both the degree of separation and the necessity to separate finer particles. An 85% efficiency filter is a prerequisite for the correct functioning of ventilation systems and to improve indoor air quality (IAQ).
A test rig for long-term tests of activated carbon filters was developed consisting of eight parallel test-filter sections. The test-rig was installed on the roof of a six storey commercial building located in the centre of Goteborg, Sweden. By this arrangement, eight activated carbon filters are tested simultaneously under realistic conditions, using the pollutants in the ambient outdoor air as challenge substances.
The cabin air filter performance is of prime importance for the air quality in vehicles. New clean filters were tested but also filters loaded with actual traffic contaminants. Both laboratory and field measurements were included in the study. Direct reading instruments and filter sampling was used for the loading rate determinations. The filter performance includes particle filtration efficiency with regards to particle size, filter loading and flow rate as well as filter pressure drop related to filter loading. Test results for these paramenters are presented.