Even when outdoor temperature is plummeting, inside an intense tornado, it’s always chilly.
A new study from Concordia proves why thats the case. In an article in the “journal of aircraft” of the American Institute of Aeronautics and Astronautics, mechanical engineering professor Georgios Vatistas looks into the case of a tornado that hit Nebraska’s Scottsbluff in 1955. During the catastrophic incident three storm chasers and broadcaster from nearest station chased the storm and hid under a basement of a stone building. As the funnel of the tornado passed overhead, they reported strange climatic changes. The temperature dropped from hot summer average to down to chilly condition until the storm-chasers felt cold. It was reported that they also felt difficult to breathe.
Vatistas who was an expert on the topic, made an analytic approach with his previously formulated mathematical formula. He made some changes in the formulated approach with the help of recent Concordia master’s student – Badwal Gurpreet Singh and Rahul Rampal (both- MASc 14).
They made some changes such as including the density variation and turbulence. “Using this new approach, we were able to identify the cause of the temperature drop inside vortices for the first time ever.” says Vatistas. “As the air pockets move from outer periphery of the vortex toward its center, the pockets expand, thereby bringing the temperature and density down.” In the Scottsbluff, Vatistas and his team found that the temperature had fallen from a comforting 27°C to 12°C. And the air density at the centre of the tornado would have dropped 20% lower than whats found at high altitude which is approximately 8000 mtrs. also known as death zone, beyond which mountaineers can not climb without an extra oxygen support. This is the clear reason why the chasers found it difficult to breathe. Luckily the tornado passed quickly and the chasers avoided asphyxiation (death due to lack of oxygen).
This study will help Engineers improve the operation of refrigeration vortex tubes, which are often used in cooling of cutting tools during machining, hot metals, various electronic components, heat seals and gas samples.