Combined ventilation and heating systems in floors demand extensive investigations about the heat transfer before they could be installed in residential buildings. For basic investigation about the heat transfer two experimental plants with different duct geometries are build in a laboratory of the University of Essen. Especially the measurements of temperature on different places of the plants are taken to determine the heat transfer at the two floors.
Mechanical systems which use common ducts for combined heating and ventilating functions are becoming popular in the Pacific Northwest (U.S.). These systems range from simple fresh-air inlets ducted to the return side of a forced air heating s stem to more complex heat recovery ventilation systems utilizing the K eating ducts for air distribution. Typical integrated systems do not have heat recovery capability.
As part of the AIVC's technical programme, study has been performed on present and advanced ventilation systems. The first part of the study presents a review on demands for basic ventilation of residences and major design considerations forventilation systems. The second part is a review on ventilation systems advanced approaches divided into: air movement control systems; flow quantity control systems; ventilation heat recovery systems; alternative ventilation energy systems.Furthermore a system for the classification of ventilation systems is suggested.
The measurements reported in this paper were carried out in a mock up of an office room, ventilated by a commercial supply air terminal consisting of 84 nozzles (characteristic dimension SqRoot of As = 0.0975 m). The test room configuration was identical to the one used within the IEA Annex 20 work. Results from isothermal supply is reported. A constant-temperature hot-film anemometer with fast dynamic response was used torecord the instantaneous velocities.
Is it possible to translate a computed flow field to a design case with different physical dimension? - This and related questions must be answered when the results of the "air flow pattern atlasM, as proposed in the IEA Annex 20, should be applied to actual ventilation systems. Looking up a case in the atlas and transforming results to an actual application is like interpolating in a table. If geometries are similar, scaling laws may be applied. The interpolation problem also arises when numerical or experimental data from literature must be translated to a case at hand.
This article discusses the application of tracer gas methods to industrial hygiene investigations. It introduces the basic concepts necessary to understand the application of tracer gas methods to particular airflow and contaminant movement measurements. It provides an overview of existing methods which can be used to obtain quantitative data on a variety of airflow and contaminant movement related questions which often are of interest to the industrial hygienist.
A new handbook, describing in details the measurement techniques which could be used to better understand the infiltration and ventilation in buildings is presented. This handbook results from the cooperation between Annex 20 and Annex 5 of the IEA ECB program. It presents the techniques for detecting and measuring as well the air leakages as the air flows in buildings and inventilation systems. Methods related to ventilation efficiency and effectiveness, like the measurement of the age of air, are also described.
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