Experimental investigation of large-scale tornado-like vortices

Abstract

Tornadoes are one of the most pressing research topics in wind engineering due to the extensive damages they impact on infrastructure and the environment. The proper scaling of experimentally produced tornado-like vortices (TLVs) against actual tornadoes is, therefore, a quintessential part of assessing tornadic damages on the built environment. The Wind Engineering, Energy and Environment (WindEEE) Dome at Western University has already demonstrated its capacity to generate TLVs characterized by length scales in the range between 1:300 and 1:150 by using only a part of the full potential of this simulator. This paper introduces a new experimental mode of the WindEEE Dome operation intending to create larger-scale TLVs in the geometric scaling approximately 1:50. In addition to the six upper fans (source of suction) and the peripheral louvers (source of swirl) that were used in the previous TLV simulations, the new tornado mode of the WindEEE Dome also utilizes the peripheral fans situated along the periphery of the testing chamber as an additional source of angular momentum in the inflow. The simulated TLV is scaled up and compared against published Doppler-radar data of an actual tornado in the United States. Our analyses show that the WindEEE Dome large-scale TLV corresponds to EF0 to EF2-rated twisters in nature. The geometric scale of the produced TLV is ~1:50. This large geometric scale of the TLVs facilitates the experimental investigation of tornadic actions on structures, including aeroelastic testing of wind-structure interactions.