The Burj Dubai is many things: World’s tallest building, financial folly, symbol of mankind’s technological triumph, and now, possibly, a mechanism for defusing tropical storms. How on Earth is that possible? It’s the chimney effect.
As pointed out in Der Spiegel, the Burj Dubai’s enormous height means that there’s an 8 Celsius difference in the air temperature at the top compared to at the base of the building. The upshot is that “If anyone ever hit upon the idea of opening a door at the top and a door at the bottom, as well as the airlocks in between, a storm would rush through the air-conditioned building.” It’s a physical phenomenon called the chimney effect.
The aerodynamic and air-pressure issues affecting tall buildings have been known for a long time, of course: The World Trade Center towers had to be carefully designed to react in the right way to winds blowing around one twin and onto the other. The Citigroup Center building in New York had to be redesigned at the very last minute lest a structural flaw let it be toppled by sudden strong winds. The Calatraver tower in Chicago has its frontage angled to deflect down-draft winds away from pedestrians at its base. And the O14 building in Dubai actually utilizes the chimney effect to cool the building down by drawing air through it.
But over at BuildingBlog they’re speculating on a rather sensational idea for the massive chimney effect the Burj Dubai would generate: Could it be used to defuse a tropical cyclone? The idea would be to strategically open a channel between the building’s base and its tip, resulting in a sudden dumping of hot air into a low pressure storm at altitude. It’s a “James Bondian” idea, according to the blog, but an attractive one–“soon you’re modifying wind-flow over whole minor continents” as well as potentially saving lives and money.
Would this work, though? Sadly, I suspect not. The amount of air you’d have to move to seriously influence a tropical storm would be much more than you could inject into altitude via the Burj building. And with a very strong storm, you could even create enough of a pressure differential to cause some seriously high-speed winds to blow through the tower, potentially tearing up the structures inside.
But does this highlight a massive missed opportunity for the building? By installing a tall elevator shaft-like channel inside, couldn’t the chimney effect have been harvested to generate electricity via an internal wind turbine? Given the horrid ecological impact of the tower, and the rocky economic situation Dubai has suddenly found itself in, this would seem to be an attractive mitigating idea from many different angles.