Cross ventilation analyzed by recording pressure distributionon the floor of wind tunnel models

Cross-ventilation is difficult to predict andcontrol because wind exhibits a large degree ofvariation in both speed and direction.Consequently, the design of a well functioningcross-ventilation system presently demandsthorough and often expensive wind tunnel andCFD investigations. If one can lower the costneeded for these investigations much will begained. This paper considers the possibility toclassify types of flows based on straightforwardstatic pressure measurements. The wind tunnelat the University of Gavle was provided with apressure plate with 400 pressure taps organizedin a square grid. Models of a house with twoopenings located opposite to each other wereplaced on the pressure plate and subjected tosteady wind flow conditions. Three distincttypes of flows were identified by systeniaticallychanging the opening size and recording therelated static pressure distribution. Theoccurrence of the different regimes can beexplained by jet flow theory. The mostimportant parameter was the internal length ofthe house divided by a characteristic length ofthe opening which is the parameter associatedwith the development of jet flow.