1. Design a Monster Duck
November 7, 2013
Dutch conceptual artist Florentijn Hofman has entertained millions around the world with his Monster Rubber Ducks.
Different sized ducks have appeared in Amsterdam, Lommel (Belgium), Osaka, Sydney, Sao Paulo, Hong Kong and Pittsburgh.
Each duck is constructed using 3D and Computer computer generated models.
The Duck that appeared in Darling Harbour, Sydney in 2013 measured approx 15 m x 15 m.
It was FIVE STORIES high.
The largest duck, which appeared in Saint Nazaire, France measured approx 25 m high or 82 ft and weighed almost 600kg or 1300 lbs.
This mega duck is over 8 stories high!!!!!
BUT how does an artist stop the wind picking up an 8 story duck and dumping it on your head?
He – Florentijn is a he – does his maths.
Here is a simple wind load formula for stormy conditions.
F = Kv2A
F = Wind Force (Newton)
K = Coefficient of Exposure = 0.5 (Engineers use standard tables for K)
v = Wind velocity = 72 kph = 20 m/sec
A = area of X-section exposed to the wind
Now, we’re going to be tricky. A 1 kg weight (eg. a litre of milk) exerts a force of 9.8 N or 1 kgf = 9.8 N on your hand. If we divide the above formulae by 10 we end up with a unit we know …. kgf.
F = Kv2A/10 kgf
If the wind force is 9,560 kgf in a storm it can easily pick up a 600kg duck. In fact, if you do the calcs, it is only in a normal wind ( 20 kph or 5 m/sec) that the duck would stay put (F = 597 kgf).
So WATCH OUT!!!!!
If that duck is not tethered to a building or pontoon it could take off and it could easily take out a school!!!!!