Measurements on three gas and two electric furnaces have been made to examine the field performance of these furnaces and their interactions with their forced-air distribution systems. The distribution systems were retrofitted as part of this study, and the impact of retrofitting on furnace performance is discussed. In addition to field measurements, this paper discusses how forced-air furnace systems are treated in proposed ASHRAE Standard l 52P and applies the resulting equations to the systems tested in the field.

A method was developed to estimate dust production and deposition rates for a ventilated airspace without a recirculation system under steady-state conditions. The method was derived from a dust mass balance equation and parameter estimation method. The measured variables required for using the method were the dust concentrations and ventilation rates of the ventilated space. The outputs of the method were dust production and deposition rates.

Modeling of delivery efficiency was performed using three levels of combining measured and default input parameters and compared to measured data from seven manufactured homes. Using values based on all measured data provided modeled efficiency results that were closest to short-term coheat efficiency results. As individual measured parameters were replaced by estimated or default values suggested by the draft version of proposed ASH RAE Standard l 52P, the agreement with measured efficiency results worsened.

This study was initiated to determine the extent of cold temperature air leakage from operable windows available in todays marketplace and the impact that this has on the energy consumption of a house. During the heating season, changes in the window's leakage characteristics, as a result of thermal and pressure effects, were to be included. At two laboratories, air-leakage tests down to-30°C were performed on 35 windows, enough to reach some general conclusions about performance.

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.

Knowledge of room air distribution, including its flow and temperature characteristics, is very important to HVAC engineers. This study numerically predicts the air distribution in a room with differentially heated vertical walls. The Rayleigh number in the room is around 2.6-3x 10¹⁰. Time averaged equations of continuity, momentum, and energy are numerically solved by the finite volume method. Three turbulence models, the "standard" k-E model, and two low-Reynolds-number k-E models, are employed to simulate turbulent natural convection in the room.

A three-dimensional, large eddy simulation (LES) model developed for studying the transport of smoke and hot gases during a fire in an enclosure is described. The model uses finite difference techniques to solve the Navier-Stokes equations with an approach emphasizing high spatial resolution and efficient flow-solving techniques. The model uses the Smagorinsky subgrid-scale model. The LES model with Smagorinsky subgrid-scale model was applied to ventilation aiiflow in a three-dimensional room.

The airflow in buildings involves a combination of many different flow elements. It is, therefore, difficult to find an adequate, all-round turbulence model covering all aspects. Consequently, it is appropriate and economical to choose turbulence models according to the situation that is to be predicted. This paper discusses the use of different turbulence models and their advantages in given situations. As an example, it is shown that a simple zero-equation model can be used for the prediction of special situations as flow with a low level of turbulence.