Flow-trace And Pressure Measuring Experiments Of Boundary Layer Wind Tunnel And Standard Building Model

Flow-trace and pressure measuring experiments of the newly-built Tongji University TJ-4 wind tunnel flow field, CAAARC standard tall building model and TTU standard low-rise building model were carried out in this research, using the advanced flow numerical visualization equipment—particle image velocimetry (PIV) and surface pressure measuring equipment — electronic pressure scanner valve(EPSV).Based on the traditional flow field validation, which is the combination of pressure measuring method using parallel pitot tube plus pressure scanner system and velocity measurement method using hot wire anemometer, the velocity uniformity and wind attack angle are checked using PIV method. Combining the merits of the traditional method and PIV method, it is proved that TJ-4 boundary layer wind tunnel comes up to the designed standard.CAAARC standard tall building model pressure measuring experiment and flow visualization experiment were conducted in TJ-4 boundary layer wind tunnel. The comparison between the results obtained from EPSV pressure measuring experiment in TJ-4 and other five international institute centers shows that the performance of TJ-4 boundary layer wind tunnel meets the requirements of carrying out wind tunnel experiment. The mean pressure coefficients obtained in uniform flow is higher than that in 10% turbulent flow by about 15 percent. In the PIV flow visualization experiment, flow separation takes place at the top and bottom edges and two large vortices behind the model that remain attached to the back of the model are observed. And the mean pressure coefficient in the backflow area which locates in the middle of the two vortices is higher than that of the adjacent points.TTU standard low-rise building model pressure measuring experiment and flow visualization experiment were conducted in TJ-4 boundary layer wind tunnel. In general, the pressure measuring result shows good agreement with results of model experiments in other institute centers in the world, and full-scale experiment results as well; however, the fluctuating pressures and largest peak suctions are often...