Abstract It is essential to investigate person-to-person contaminant transport in mechanically ventilated spaces to improve air distribution design and reduce the infection risk from airborne infectious diseases. This paper provides a systematic study of the effects of ventilation mode, ventilation rate, and person-to-person distance on person-to-person contaminant transport. This study first c...

In chamber experiments, we investigated the effectiveness of a task ventilation system with an air supply nozzle located underneath the front edge of a desk and directing air toward a heated mannequin seated at the desk. The task ventilation system provided outside air, while another ventilation system provided additional space cooling but no outside air. Test variables included the vertical an...

The pelvis of crocodilians is highly derived in that the pubic bones are isolated from the acetabulum and are attached to the ischia via moveable joints. We examined the possible role of this unusual morphology in lung ventilation by measuring ventilation, abdominal pressure and the electrical activity of several abdominal and pelvic muscles in the American alligator (Alligator mississippiensis...

Health care facility ventilation design greatly affects disease transmission by aerosols. The desire to control infection in hospitals and at the same time to reduce their carbon footprint motivates the use of unconventional solutions for building design and associated control measures. This paper considers indoor sources and types of infectious aerosols, and pathogen viability and infectivity ...

Ventilation flows generated by a localised heat source within room containing two openings to the ambient environment are examined. The representative of doorway and high-level vent, steady two-layer stratification well-mixed fluid is established for all cases considered. Classical displacement ventilation flow observed when interface between layers above height doorway. Displacement can persis...

Using computational fluid dynamics (CFD) techniques to model buoyancy-driven airflows has always proved challenging. This work investigates CFD modelling of buoyancy-driven natural ventilation flows in a single-storey space connected to an atrium. The atrium is taller than the ventilated space and when warmed by internal heat gains producing a column of warm air in the atrium and connect space ...

Buoyancy-driven displacement natural ventilation in a simple multi-storey building structure is investigated. The storeys are connected to a common atrium and top-down-chimneys, and the internal heat gains of the storeys are represented by localised point heat sources on each floor. The heat sources generate thermal plumes which entrain the surrounding air and transport warm air upwards. Simple...

The environment inside airliner cabins has attracted increasing attention. Instantaneous airflow, as one of the fundamental parameters airflow field, affects aspects cabin such occupant comfort and airborne disease transmission. This study evaluated characteristics instantaneous in with different ventilation systems (mixing displacement ventilation) focused on region above passengers' heads, wh...

introduction: tuberculosis (tb), with different types of respiratory tract involvements, has a high rate of mortality all around the world. endobronchial involvement, which is a slightly common tuberculous infection, requires special attention due to its severe complications such as bronchostenosis. aim of study of this study was describes, one type of pulmonary tuberculosis with less diagnosed...