Direct comparison measurements were made between various prime/storm window combinations and a well-weatherstripped, single-hung replacement window with a low-e selective glazing. Measurements were made using an accurate outdoor calorimetric facility with the windows facing north. The double-hung prime window was made intentionally leaky. Nevertheless, heat flows due to air infiltration were found to be small, and performance of the prime/storm combinations was

A new generally applicable model for calculating the surface emissions of VOCs (volatile organic compounds) from building materials and the VOC instantaneous distributions in the materials is developed. Different from the mass transferbased models in the literature, it doesnt neglect the mass transfer resistance through the air phase boundary layer. Results obtained by using the presented model are validated with experiments from the literature. By normalizing the model, the

Air age is an important index to evaluate indoor air quality in ventilated rooms. The traditional definition of air age is limited to the indoor part (i.e., the air age at the inlets of air supply diffusers is assumed to be zero). Total air age extends the traditional air age concept by considering the influence of air delivery process on air age distribution. In this paper, we report the development of an algorithm to calculate total air age in a room ventilated by multiple air-handling units (AHUs).

This research evaluated the effectiveness of local supply ventilation in controlling air quality at or near workers’ breathing zones in livestock confinement buildings. Commercially available ceiling (box-type) diffusers and local supply ventilation syste

The infiltration term in the building energy balance equation is one of the least understood and most difficult to model. For many residential buildings, which have an energy performance dominated by the envelope, it can be one of the most important terms. There are numerous airflow models;
however, these are not combined with whole building energy simulation programs that are in common use in North America. This paper describes a simple multizone nodal airflow model

Several thermal building simulators also allow coupled modeling of bulk air movements using airflow network models.However, solving the combined flow and thermal problem can be problematic, both in the context of traditional building simulators and for modern environments, where both airflow and thermal models are formulated as sets of differential-algebraic equations (DAE). For variable-time-step DAE-basedsimulators, difficult coupled problems often lead to small time steps and slow simulations.

This paper presents the objectives and results of the initial stage of an ongoing research project on coupling of building energy simulation (BES), airflow network (AFN), and computational fluid dynamics (CFD) programs. The objective of the research underlying this paper is to develop and verify a prototype cooperative BES, AFN, and CFD design environment for optimization of building energy performance and indoor environment.

The impact of infiltration and ventilation flows on energy use in commercial buildings has received limited attention. One of the reasons for this lack of study is that the commonly used programs for estimating the energy use of buildings do not incorporate the interzonal airflow modeling techniques
required to adequately account for the effect of these factors on energy usage. To address this issue and provide insight into the impact of these flows, the CONTAM airflow modeling tool

A adaptive controller was devised and implemented within the ESP-r simulation program to support the conflation of CFD with dynamic whole building thermal simulation. This controller manages all interactions between the coupled thermal and CFD modeling domains. It employs a quasi-steadystate modeling approach, wherein the separate CFD and thermal modeling domains operate in tandem and exchange information at their model domain boundaries on a per-time-step basis. A double-pass modeling approach is employed.

This paper describes a fault detection method developed for application to variable-air-volume (VAV) boxes. VPACC (VAV Box Performance Assessment Control Charts) is a fault detection tool that uses a small number of control charts to assess the performance of VAV boxes. The underlying
approach, while developed for a specific type of equipment and control sequence, is general in nature and can be adapted to other types of VAV boxes. VPACC has been tested using emulation,