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Blog
Can Santa deliver all the presents this year?
December 24, 2007
The answer to this question is provided by guest blogger Cathy Jain, who is an independent marketing consultant.
Father Christmas’ job is becoming more difficult each year. The population is growing, and therefore the number of stops is increasing.
Between Christmas Eve and Christmas Day, Santa's route around the planet includes stops at nearly 2 billion homes. He does have 48 hours to work with—assuming the logical choice of traveling against the Earth's rotation. This gives him about 86 microseconds at each stop to go down the chimney, drop off the presents, enjoy cookies and milk, and get back on his sleigh. Santa’s sleigh is also moving at 3,000 times the speed of sound for all of this to happen.
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| Unstreamlined objects create a large high-pressure zone in front and a low-pressure wake behind, producing a large form drag. Source: Cathy Jain and Control Engineering |
As the population increases, the only way for Santa to make more stops in the same time is to have a more streamlined sleigh. A non-streamlined object (such as a flat plate) can have ten times more form drag than a streamlined object of comparable frontal area. The peak pressure in front of the two shapes will be the same, but the streamlined shape causes the air to accelerate, so the region of highest pressure is smaller, and more importantly, the streamlined shape cultivates high pressure behind the object that pushes it forward, canceling most of the pressure drag. This is called pressure recovery.
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| Streamlining drastically reduces the high-pressure zone ahead and virtually eliminates the turbulent low-pressure wake, reducing form drag by a up to 10X. Source: Cathy Jain and Control Engineering |
In short, Santa needs a streamlined delivery process—literally.
Posted by Charlie Masi on December 24, 2007 | Comments (0)