Longitudinal ventilation is a common technique for smoke management during a fire accident within tunnels. In this paper, fire and smoke movement behaviour in longitudinally ventilated tunnels is investigated focusing on critical ventilation velocity. Firstly, critical velocity (VC) is evaluated for different heat release rates and results are compared and verified with model scale experimental data. Secondly, two fire scenarios inside tunnels with different cross sections are arranged and the reliability of some existing correlations for VC is explored.

A common room-heating technique involves the use of a wall-mounted radiator without forced convection. The cold surrounding air passes adjacent to the warm surfaces of the radiator where it absorbs heat and gains momentum to rise along the wall surface and finally circulate in the entire room. Understanding the properties of heated airflows is important for several purposes. To understand the flow process it is important to identify where the transition from laminar to turbulent flow occurs and to quantify the turbulent fluctuations.

Electric fans used for cooling or local ventilation are common household appliances around the world, especially in developing countries. They offer many advantages such as low cost and energy savings, as well as easy implementation. However, the airflow from fans is often considered to be less comfortable than the sensations produced by natural winds. In order to avoid the draught induced by fans, and to investigate dynamic airflow characteristics of household fans, an anemometer was utilized to measure the corresponding time series of the air velocity.

In this paper, the numerical and experimental performance of a new Thai Modern Façade (TMF) are investigated. Two configurations were considered namely, the Thai Modern Façade wall (TMF) and the Thai modern façade wall with fin (TMF-WF). The coupled governing equations as well as boundary conditions are solved using the finite element method (FEM) via COMSOLTM Multiphysics. Temperature profiles and flow field of the TMF and TMF-WF are reported and discussed.

This paper reports on research to analyze the indoor air quality (IAQ) and the concentration and varying patterns of CO2, formaldehyde and TVOC in commercial buildings located in Chongqing, South-West China. Two buildings were monitored during the day over two weeks in the summer period. One was a completed building that had been fully operational for several years. This building is termed the ‘non-renovated’ building. The other was a commercial building of similar age that was currently undergoing renovation on one of the main retail floors.

The aim of this study was to determine the concentration of Legionella pneumophila in the surface dust of the air ducts of central air conditioning systems and evaluate its effects on indoor air quality. Thirty dust samples were collected from thirty air ducts and analyzed using real-time TaqMan PCR targeting the mipgene.

A heat recovery ventilator (HRV) is used to create a balanced ventilation system in residential buildings and as an energy-saving measure. HRVs bring in outside air which is tempered with outgoing stale air, with only the small energy penalty of the blower power to overcome the pressure drop in the HRV. HRVs have been used in cold climates and have often performed poorly due to frosting failure.