Tests a method which determines the infiltration of air and radon from the soil to a building. Makes measurements of total air flow along with usual airtightness tests. Describes practical tests in a detached house with a raft foundation on a gravel esker, and determines the permeability curves for thewhole house and the raft alone, and also the permeability of the soil to air. Describes the way the results are used for determination of air infiltration in different climatic conditions, and tests different radon reducing methodsusing the previously developed system analysis.
Discusses the extension of an infiltration predicting technique to the prediction of inter-room air movements. Air flow through openings is computed from the ASHRAE crack method together with a mass balance in each room. Verifies technique by comparison to published experimental results. Results indicate that the simple model provides reasonable results for complex 2 way flows through openings. The model is as accurate as the available data, about+-20%.
Studies the techniques and issues related to evaluating the airtightness of homes. The first section discusses the physics of air infiltration and the techniques used to measure infiltration rates. Also discusses pressurization testing and its relation to infiltration. The second section presents experimental work aimed at several questions raised in the first section. A long term experiment involving weekly pressurization testing of a home reveal the short-term reproducibility of the test results and the seasonal variation in a home's tightness.
Presents a model for computing the infiltration and air flow between rooms of a multi-room building in terms of basic principles of fluid mechanics. Incorporates model into a comprehensive loads-predicting computer program, and calculates air flows, room temperatures and heating loads for a typical townhouse. When the inter-room openings of a low-rise structure are large compared to the envelope openings, the infiltration and total load can be accurately and more quickly computed by assuming no resistance to air flow between rooms.
Compares LBL infiltration model predictions with air infiltration and weather data collected by MITU. Examines 4 simplifying assumptions in the model:1. The flow through cracks in the building shell can be approximated by orifice flow 2. ""Wind-induced and stack-induced infiltration can be added in quadrature 3. Wind-induced infiltration can be represented by averaging the values for 3 typical aspect ratios 4.
Uses a validated multi-cell mathematical model of air infiltration to analyse the influence of various ventilation strategies on air distribution and energy demands. Assesses the performance of both natural and mechanical systems for two sets of climatic conditions and for two levels of airtightness. Shows that natural ventilation rates are highly dependent on climate. Additionally, air movement is a function of wind direction and stack effect.
Describes the Energy Performance Design System (EPDS) which is a simplified procedure for energy analysis based on extensive field testing, laboratory experiments and computer modelling. Provides a simple procedure for designing and evaluating the performance of energy-efficient homes. Describes thedevelopment of the simplified air infiltration model used in EPDS. The starting point for model development was a series of field studies on air infiltration conducted 1978-1981.
Describes a computer program developed for the analysis of residential building thermal loads and space heating and cooling energy use. It is capable of modelling the simultaneous heat balances on multiple spaces, building air flows by infiltration and natural and forced ventilation, including thermostatically controlled through the house ventilation, detailed solar gain, part load performance of central and unitary heating and cooling systems, and thermostat droop and cycling characteristics.
Presents various measurement and inspection techniques for assessing the thermal performance of the exterior envelopes of buildings. Inspection techniques include the use of ground-based infra-red thermographic surveys, aerial infra-red surveys, tracer gas air infiltration measurements, pressurization tests for measuring the tightness of the building envelope, and spot radiometer surveys for detecting gross defects. Also considers heat flow meters, a portable calorimeter and a microprocessor-driven envelope testing unit. Provides recommended procedures for each technique.
Presents a review of the main methods used for the study of air movement. Includes sections on physical modelling (wind tunnel modelling etc), analogue (water and electrical) models of air movement, mathematical models and digital computer analogues, and full scale investigations including pressurization andtracer gas techniques.
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