English

Currently accepted best design practice for controlling airborne particulates in the hospital operating room relies on air flow type (laminar) and direction (down from ceiling). This is typically in the form of large arrays of laminar diffusers. These arrays are limited, or impacted, by deltaT and the need to have other ceiling-mounted equipment in the operating room. The industry could benefit from a scalable pre-engineered system that overcomes these inherent limitations. Such systems could be qualified by actual microbial testing

Experiments with a fan-driven convector used for both heating and cooling are described in this paper. Only the cooling situation is considered. The convector is positioned in the upper corner of the room, and from there the cold air is let out through the device along the ceiling. The airflow coming from the diffuser is partly controlled by the momentum flow and partly from gravity forces, where the thermal load in the room and the temperature difference between room air and supply

The issue of assessing existing buildings in terms of their vulnerability to extreme man-made intentional threats has acquired great urgency in recent years. Several federal and professional agencies, as well as individuals, have been working on this issue, and a number of analytical methods and tools have been suggested and developed. The field has reached a level of maturity where it is now necessary to synthesize existing work and define the types of specific consensus and research areas that need to be studied from the buildings perspective.

An experimental study and model analysis were performed to assess the effectiveness of commercially available in-room air cleaners in minimizing the impact of a hazardous aerosol released in a building. Two air cleaners were evaluated: a HEPA-type air cleaner and an electrostatic
precipitator.

In raised-floor data centers, the distributed air leakage, which refers to airflow through the gaps between the floor panels, reduces the amount of cooling air available for direct cooling of computer equipment. In this paper, we discuss a methodology for predicting this air leakage, using an airflow

The heat loads of servers and storage devices are continuing to increase at a rapid rate. These increases are causing data center operators to struggle with how to provide adequate cooling for these high-powered racks. Over the past four to five years there have been a number of journal articles published related to the cooling of high-density data centers. The purpose of this paper is to review all of these articles and capture the recommendations/guidelines that pertain to best

The dimensionless capture index (CI) is proposed as a cooling performance metric based solely on the airflow patterns associated with the supply of cool air to, or the removal of hot air from, a rack. The capture index is typically a rack-by-rack metric and has values between zero and 100%;

Data center facilities that house computer equipment represent a high capital investment and are typically designed to function for at least a few years, often without any down time. The computer equipment is usually designed with the assumption of rack air inlet temperatures in the 20-30C range. Although there are many different perspectives for optimizing such a computing facility, ensuring device reliability by delivering uninterruptible power and cool air to the inlet of the electronics remains the most important goal.

In low-energy building design, energy consumption due to space conditioning is responsible for over 30% of total energy consumed in commercial buildings. In an effort to evaluate low-energy building designs, two commercial office buildings were each monitored for 16 months. A comparison of the two buildings, with different ventilation strategies but located in the same climate, is presented. One is naturally ventilated without mechanical chillers, and the other uses a raised floor system combined with a chilled ceiling for space conditioning.

This paper describes the Frederick Lanchester Library at Coventry University, UK, that incorporates natural ventilation, daylighting and passive cooling strategies and presents the energy consumption and the internal temperatures and CO2 levels recorded in 2004/2005. The performances are good, the building uses under half the energy of a standard air-conditioned building and can keep the interior comfortable and up to 5C below ambient.