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LoopDA -- A Natural Ventilation System Design and Analysis Tool



William S. Dols, Steven J. Emmerich


The Loop Equation Design Method has been proposed for sizing ventilation airflow components of natural and hybrid ventilation systems. While the loop design method has been demonstrated on a limited basis, the method has been automated in order to better evaluate its reliability under a more controlled, i.e., less error-prone, environment. This paper describes a computer program that implements the Loop Equation Design Method of sizing the openings of naturally ventilated buildings. The tool, referred to as LoopDA for Loop Design and Analysis, is integrated with the existing multi-zone IAQ model CONTAMW. LoopDA provides the designer of natural ventilation systems with an environment in which to perform and document the process of designing the opening sizes of natural ventilation systems and analyzing the system behavior under a variety of operating conditions. This paper describes the first version of the LoopDA program, provides an example of its application to the design of a naturally ventilated building and describes needs for future enhancements to the tool to increase its usefulness within the design community.
Conference Dates
August 11-14, 2003
Conference Location
Eindhoven, NL
Conference Title
IBPSA International Conference and Exhibition on Building Simulation


airflow analysis, building technology, computer program, design tool, indoor air quality, multizone analysis, natural ventilation


Dols, W. and Emmerich, S. (2003), LoopDA -- A Natural Ventilation System Design and Analysis Tool, IBPSA International Conference and Exhibition on Building Simulation, Eindhoven, NL, [online], (Accessed May 18, 2024)


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Created August 1, 2003, Updated February 19, 2017