Air conditioning, as we know it, providing thermal comfort by mechanical means, first appeared in buildings about one hundred years ago. During that time it has had major influence on the evolution of the design buildings. This paper reviews the development of providing cool comfort in office buildings from the pre-active era of the middle of the 19th century through the rise of air conditioning in the mid 20th century to the current state of the art.
A field study was carried out to assess the impact of installing a desktop task/ambient conditioning (TAC) system at 42 selected workstations within three San Francisco office buildings occupied by a large financial institution. In this study, field measurements, including subjective surveys and physical monitoring, were performed both before and after the TAC system installation to evaluate the impact of the TAC system on occupant satisfaction and thermal comfort, as well as the thermal environments within the office buildings.
Typical HVAC noise may produce an uncomfortable environment, leading to the associated problems of general dissatisfaction and reduced productivity. It is not sufficient to have good thermal, lighting, and air cleanliness conditions if the noise is disturbing. In this paper, noise comfort is considered, with special emphasis on the developing criteria for low-frequency noise.
The subject of this paper is the experimental determination of the flow characteristics of three-dimensional wall jets. The jets were produced from a diffuser with a rectangular outlet. The diffuser outlet size and flow rate were varied to produce both low and high outlet aspect ratios and Reynolds numbers. Velocity profile measurements were made to determine the centerline velocity decay and the extent of the lateral and vertical spread of the jet.
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