LABORATORY SIMULATION OF TORNADIC WIND LOADS ON A CYLINDRICAL STRUCTURE

Ward's tornado simulator has been modified to study the interaction of tornadic flowfields with structures. Measurements with and without swirl have been made of the pressure on the surface of a cylindrical model placed in the simulator. The model, similar to a nuclear reactor containment building, is a circular cylinder with a hemispherical roof. Results for the surface pressure coefficient are presented for swirl angles of 0° and 45° with the model at two positions in the simulator: 1) the convergent zone, 2) at the boundary of the convergent and convection zone. The tornado-like vortex is observed to induce a circulation about the cylinder thereby reorienting the net force away from the imposed swirl angle.