The use of an underfloor plenum to deliver conditioned air directly into the occupied zone of a building is one of the key features that distinguish underfloor air distribution systems from conventional ducted overhead systems. This paper describes the development, validation, and application of a computational fluid dynamics (CFD) model for predicting the airflow and thermal performance of underfloor air supply plenums. To provide validation data for comparison with the

Experiments with room air distribution that is generated by a radial ceiling-mounted diffuser and a diffuser generating flow with swirl are compared with the air distribution obtained by mixing ventilation from a wall-mounted diffuser, vertical ventilation, and displacement ventilation. The air distribution generated by a radial diffuser is partly controlled by the momentum flow from the diffusers and partly from gravity forces where the thermal load and the temperature difference between room air and supply air deflect the radial wall jet down into the occupied zone.

Volatile organic compounds (VOCs) are major gas-phase indoor air pollutants, and filtration is one of the promising methods to control indoor VOC concentration levels. An adsorption technique is commonly used for filtration of VOCs using adsorbents such as activated carbon. Unlike a particlefilter system, the applications of gas-filter systems have not been widely studied, and standards for the evaluation of gasfilter systems do not exist. As groundwork for standards development, this study proposes an experimental method that can evaluate the performance of gas filters in removing VOCs.

Because of their ability to improve building air quality and their potential to reduce energy usage in some climates by allowing more conditioned air recirculation, use of gas contaminant filters in buildings is increasingly considered. Air cleaning is an option under ASHRAE Standard 62 and is

This paper provides a method for verifying the accuracy of computer models that simulate the performance of the airhandling components of four types of heating, ventilating, and air-conditioning systems: the dual-fan VAV dual-duct system, the single-zone system, the four-pipe fan coil system, and the four-pipe induction system. To accomplish this, a detailed description of each system and its operating parameters was developed and a set of eight test conditions was generated, consisting of carefully chosen space loads and weather conditions.

A new all-electric retail store located in Montreal, Canada, incorporates several design features to maximize the interactions between various building components. The twostory, high-performance, "green" commercial building is the result of an integrated energy design process and features

Two high-performance prototype houses were built in Carbondale, Colorado, as part of the US Department of Energy’s Building America (BA) Program. Each prototype was a 1256 ft2 (117 m2), one-story, three-bedroom house and met the local requirements for aff

Electronics densification is continuing at an unrelenting pace at the server, rack, and facility levels. With increasing facility density levels, airflow management has become a major challenge and concern. Hot spots, air short-circuiting, and inadequate tile airflow are a few of the issues that are
complicating airflow management.
This paper focuses on a thermal management approach that simplifies facility airflow management in a cost-effective and efficient manner. Implementation of the technology was undertaken with the DOEs Pacific Northwest National Laboratory.

This paper investigates the ability of intermediate models such as zonal models to predict environmental conditions in a room. The first part compares experimental data to zonal andconventional k-e computational fluid dynamics model predictions in a mixed-ventilation room. Then, in order to investigate the impact of building material moisture adsorption and desorption processes on indoor air humidity and predict humidity distribution in a room, a zonal model was integratedwith a building material moisture transfer model, based on the conservation of energy and dry air and water vapor mass.

This paper presents the discrepancies in applying the power-law model (PLM) for predicting indoor airflow distribution and the methodologies employed to improve this model.First, investigation was made to find an appropriate K value (flow coefficient) for use within the PLM (using the same K value for each cell). Values other than 0.83 were considered, and the result revealed that values other than K = 0.83 could not affect the prediction of the PLM and that K can be given any value, such as 1.0.