Monthly Archives: April 2014

Turbines and whales?

Whales are just like any other fish right? whats so different about them? Their massive size. They have been swimming around the ocean for a long time now, and evolution has enabled them to be a very efficient form of life. They can dive huge distances. They can power their movement with very efficient fins and a tail.

In 2004, scientists at Duke University, West Chester University and the U.S. Naval Academy discovered that the bumps at the front edge of a whale fin greatly increase its efficiency, reducing drag by 32 percent and increasing lift by 8 percent. Companies like Whale Power are borrowing this concept and creating wind turbine blades that greatly boost the amount of energy created per turbine. Other companies are applying the idea to cooling fans, airplane wings and propellers.

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Passive cooling – a revolution

with constant increasing temperatures, and constant usage of electricity to try and over come the heat, the world is slowly coming face to face with a huge problem of depletion of resources. Although, nature again saves us. The Eastgate complex in Zimbabwe, is a 324000 square foot complex. it is huge, and in the hot climate of a place like Zimbabwe, its primary cooling method is natural ventilation. Engineers from Arup, led by Mick Pearce, got the inspiration from termite wounds. Termites need their homes to be at an exact temperature of 87 degrees Fahrenheit, throughout a 24 hour range of 35 at night and 104 at day. The solution was a passive-cooling structure with specially designed hooded windows, variable thickness walls and light colored paints to reduce heat absorption.

 

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Self cleaning paints – Lotus leaf

Paint is a very important thing in today’s world, and is used widely in rooms, buildings, cars, and possibly everything. It is quite useful, but it also has harmful environmental aspects. So, a company called Sto AG from Germany has developed a coating for paints which has a water repellent surface, quite like that of a lotus leaf. It was developed by professor Wilhem Barthlott, from university of Bonn in Germany. He got the idea after  looking for environment friendly alternatives to toxic cleaning detergents to reduce environmental impacts. He got the answer after looking at the extremely hydrophobic surface of the lotus leaf. He asked the question ‘How does nature clean surfaces?’ It became obvious that nature doesn’t use detergents at all – instead it designs self-cleaning surfaces with hydrophobic properties.

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Velcro – most prominent example of nature in science

Velcro was invented in the 1940’s. One of the biggest and most well used example of bio mimicry, it is used in our day to day life as straps in bags, in shoes, packets, and various other places. It was a life changing discovery for Swiss inventor George de Mistral, who found that one day, after bringing his dog home from a walk, there were cockle burs stuck on his dog and his pants. He studied them under a microscope, and observed their natural hook like shape, which inspired him to design the popular material, Velcro. How it works is, that it has a 2 sided fastener, one with hooks like burrs, and one with soft fabric like plants. The result was the famous “Velcro” coming from the french words, ‘velour’ and ‘crochet’.51311029_93e046e535_o      why-do-Velcro-fasteners-make-a-ripping-sound-when-they-are-pulled-apart