AIVC - Air Infiltration and Ventilation Centre

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Effect of Residential Ventilation Techniques for Hot and Humid Climates on Indoor Concentrations of Volatile Organic Compounds

Mechanical ventilation may be necessary to provide adequate ventilation in new houses due to the relatively low rates of infiltration achieved in new construction. However, in hot and humid climates, increased ventilation may raise indoor humidity to an undesirable level. A study was undertaken by the Florida Solar Energy Center (FSEC) to evaluate the humidity effects of different mechanical ventilation strategies for such climates. The study was conducted in a new 141-m2 manufactured house sited at the FSEC campus.

Effects of air infiltration on the effective thermal conductivity of internal fiberglass insulation and on the delivery of thermal capacity via ducts

Ducts that carry heated or cooled air are often internally lined with fiberglass for acoustic control and thermal insulation. If the inner face of the fiberglass liner is permeable to air, air flow in the duct may induce convection in the fiberglass and thereby increase the liners thermal conductance (the reciprocal of its thermal resistance). In fiberglass-insulated flexible ducts with air-permeable and impermeable inner cores, the "temperature-drop" method was used to measure the variation of the thermal conductances with duct air velocity.

Effects of Duct Improvement and ENERGYSTAR Equipment on Comfort and Energy Efficiency

Residential thermal distribution systems have significant energy and comfort implications due to losses from the distribution system in the form of leakage and conduction and poor distribution from room-to- room within the house. Also, poor mechanical equipment performance, and the interactions between the distribution system and the equipment act to further reduce system capacity and thermal comfort.

Effects of variable wind speed and direction on radon transport from soil into buildings: model development and exploratory results

We describe a novel modeling technique, based on Duhamel's theorem, to study the effects of time-varying winds on radon transport in soil near buildings. The technique, implemented in the model RapidSTART, reduces computational times for transient, three-dimensional, wind-induced soil-gas and radon transport by three to four orders of magnitude compared with conventional finite-dierence models.

Energy effectiveness of duct sealing and insulation in two multifamily buildings.

Energy losses from forced air distribution systems have a significant impact on the energy efficiency of buildings. Little work has been done to quantify these losses in apartment buildings. In this paper we will discuss field measurements made on four forced air heating systems to evaluate the duct system energy losses to unconditioned basements. The apartments were heated by natural gas furnaces located in the basements. The systems had bare sheet metal ductwork exposed to the basement conditions.

Energy efficiency in California laboratory type facilities.

The central aim of this project i s to provide knowledge and tools for increasing the energy efficiency and performance of new and existing laboratory-type facilities in California. We approach the task along three avenues: (1) identification of current energy use and savings potential, (2) development of A Design Guide for Energy-Efficient Research Laboratories, and (3) development of a research agenda for focused technology development and for improving our understanding of the market 

Energy-related indoor environmental quality research: A priority agenda

A multidisciplinary team of IEQ and energy researchers has defined a program of priority energy-related IEQ research. This paper describes the methods employed to develop the agenda, and 35 high priority research and development (R&D) project areas related to four broad goals: 1) identifying IEQ problems and opportunities; 2) developing and evaluating energy-efficient technologies for improving IEQ; 3) developing and evaluating energy-efficient practices for improving IEQ; and 4) encouraging or assisting the implementation of technologies or practices for improving IEQ.

Evaluation of Commercially AvailableTechniques and Development of Simplified Methods for Measuring Grille Airflows in HVAC Systems

This report discusses the accuracy of flow hoods for residential applications, based on laboratory tests and field studies. The results indicate that commercially available hoods are often inadequate to measure flows in residential systems, and that there can be a wide range of performance between different flow hoods. The errors are due to poor calibrations, sensitivity of existing hoods to grille flow non-uniformities, and flow changes from added flow resistance.

Evaluation of flow capture techniques for measuring HVAC grille airflows

This paper discusses the accuracy of commercially available flow hoods for residential applications. Results of laboratory and field tests indicate these hoods can be inadequate to measure airflows in residential systems, and there can be large measurement discrepancies between different flow hoods. The errors are due to poor calibrations, sensitivity of the hoods to grille airflow non-uniformities, and flow changes from added flow resistance.