Whole-building airflow network characterization by a many pressure states (MPS) technique.

Included in applications of multizone airflow and contaminant dispersion models to specific buildings are air quality diagnosis, weatherization, smoke control, and pressure balancing for laboratory hood safety. States that uncertainties in model inputs mean that the benefits of these applications are not being fully realized. Emphasises the need for an economical test method that is as accurate but less intrusive and faster than incremental or component-by-component blower door testing. The article reviews existing methods to measure interzonal flows by tracers and flow-pressure network parameters by pressurisation tests. The paper also presents a method based on simultaneous measurement of all zone pressures within a given control volume and flow measurements on a few selected interzonal paths. Flow rates at a subset of flow measuring locations are controlled during testing to take on two or more values. Constrained, nonlinear least squares analysis produces the power law parameters for each two-port aggregate flow path within the topology. By relying mainly on zone pressure measurements and a rich set of HVAC or blower door induced flow pressure excitation states with relatively few flow measuring stations, testing cost and effort are reduced. The authors report the results of applying the method to a two-story test building. The article also outlines potential application to fault detection, acceptance testing, continuous commissioning, smoke dispersion and other problems of building performance.