04-11-2014, 02:43 PM
Abstracts: . A powerful fan system moves air past the object; the fan must have straightening vanes to smooth the airflow. The test object is instrumented with a sensitive balance to measure the forces generated by airflow; or, the airflow may have smoke or other substances injected to make the flow lines around the object visible. Full-scale building are sometimes tested in large wind tunnels, but these facilities are expensive to operate and some of their functions have been taken over by computer modelling. In addition to building, wind tunnels are used to study the airflow around large structures such as bridges or vehicles.