What is the Coanda Effect?
The Coanda effect states that a fluid or gas stream will hug a convex contour when directed at a tangent to that surface. A Coanda effect can be demonstrated by placing the back of a spoon against a running stream of water. The pattern of the water will conform to the spoon’s curve. This was discovered in the 1930s by a Romanian named Henri-Marie Coanda. What is unusual about the Coanda effect is the fact that the fluid or gas flow is pulled so strongly by a curved surface. With a tap, the water will be projected out at a remarkable distance. The degree to which the water and the curved surface remain attached goes beyond the expected. A concave curve will naturally push the flow, but the fact that a convex one would react so strongly to fluid or gas is unusual. Coanda discovered and tested his effect on an airplane. He studied his aircraft for more than 20 years to prove that air along the wing of the plane will be deflected downward due to the wing’s shape. The air leaves the wing, p
Very simply, the COANDA (or ‘wall attachment’) EFFECT is the tendency for a moving fluid (either liquid or gas) to attach itself to a surface and flow along it. Displayed above is an image of a girl and a few soldiers. Soldiers are marching forward in straight line. Each soldier holds hand of his neighbor. Suddenly outsider soldier caches a hand of a girl standing on a sidewalk. See what happens. This is simplest explanation of Coanda effect. Note: it is assumed, that “soldiers” are some fluid elements, not single molecules. One way of explaining this effect is to understand that as a fluid moves across a surface, and certain amount of friction (called skin friction) occurs between the two surfaces (friction is that force that slows down or prevents two surfaces from moving across each other). This friction tends to slow down the fluid as it moves across the other surface. This resistance to the flow of the fluid will then pull the fluid towards the other surface, making it stick to it
Displayed above is an image of a girl and a few soldiers. Soldiers are marching forward in straight line. Each soldier holds hand of his neighbor. Suddenly outsider soldier caches a hand of a girl standing on a sidewalk. See what happens. This is simplest explanation of Coanda effect. Note: it is assumed, that “soldiers” are some fluid elements, not single molecules. Very simply, the COANDA (or ‘wall attachment’) EFFECT is the tendency for a moving fluid (either liquid or gas) to attach itself to a surface and flow along it. One way of explaining this effect is to understand that as a fluid moves across a surface, and certain amount of friction (called skin friction) occurs between the two surfaces (friction is that force that slows down or prevents two surfaces from moving across each other). This friction tends to slow down the fluid as it moves across the other surface. This resistance to the flow of the fluid will then pull the fluid towards the other surface, making it stick to it
