Modern aerodynamics works with one of the key effects that becomes essential for airplanes to fly. This effect is known as Coanda effect. The Coanda effect is something difficult to explain but it becomes too important an element in such a way that it has become the basis of the development of aerial vehicles.
In this article, we're going to tell you what the Coanda effect is and its importance.
What is the Coanda effect
To explain this effect, imagine a lit candle. If we blow out this candle, it will happen instantly. If we perform the same exercise, but place a reasonably sized box between the candle and us, it's normal to think that if we blow, the air will disperse to both sides and won't hit the candle. However, if we use a wine bottle instead of a box, the result won't be the same. Logic leads us to think that the air will also disperse to both sides and won't extinguish the candle.
Although it seems somewhat surprising, the candle can be extinguished thanks to the Coanda effect. And is that the Coanda effect explains the curvature of fluids when it comes into contact with a solid body. Fluids acquire a change in movement and displacement when they collide with a solid body.
It can be said that the Coanda effect is a series of events capable of describing the behavior of a fluid when it impacts a surface. It is used as a principle stating that all fluids tend to be attracted to nearby surfaces rather than bouncing or deflecting. This is the opposite of what happens with a solid. If a solid collides with another solid, it will normally bounce and deflect. However, in the case of fluids, they are attracted to the surface of the solid.
To delve deeper into aviation, it is recommended to study the principles that govern the flight of aircraft.
Experiment to corroborate the Coanda effect
If we carry out the above experiment, we can see that the air tends to follow the curved path of the bottle instead of deviating to the sides. If we throw a tennis ball against the wine bottle, we see that the trajectory of the ball will be altered, but it will not be parallel to the contour of the bottle. This helps us to extract the necessary information to know that a fluid will follow the path around a solid.
In simple terms, the viscosity of air is the primary factor that causes the Coanda effect. When the fluid first impacts a body with a smooth, curved contour, the fluid's viscosity causes the particles to tend to adhere to the solid's surface. This creates a uniform, parallel film around the solid's surface. This tendency could be compared to forming a film around the body's contour, like plasticine.
All the particles in the fluid, in this case the air, they subsequently impact the body and generate new layers parallel to the initial one. This is how a deviation is generated in the fluid path.
Utility and importance
The Coanda effect has been demonstrated and is used daily in aviation and motor racing. It's important to understand that, in order to optimize vehicle morphology, the effect of air friction is essential. If we know that fluid particles adhere to the surface, we can design better aerodynamic shapes. A widely used example of the Coanda effect is Formula 1 single-seater cars. The area with the sidepods takes advantage of the Coanda effect to channel large amounts of air toward specific areas, such as the underbody, diffusers, and spoilers. All of these elements of a single-seater directly affect grip and top speed.
This has made the Coanda effect one of the essential pillars of motorsports and aviation. The same thing happens with airplanes. On the wings, the air's trajectory undergoes a slight curvature, which helps generate forces that keep the plane in the air. The air curves, and together with the pressure drop and Newton's third law, we understand all the forces acting on the airplane's wing.
Thanks to the Coanda effect, air and other fluid flows can be corrected and directed, allowing engineers to design more efficient means of transportation. This influence of the Coanda effect on a vehicle's aerodynamics it is an important element in building safer and faster vehicles. In addition, these aerodynamic designs help save significant amounts of fuel, as they help reduce friction with the air.
Characteristics and curiosities
The Coanda effect relates to the reflection of fluids around an object. If we analyze all the forces and atmospheric pressure exerted by the atmosphere on low-speed flight, air is considered not just a fluid, but an incompressible fluid. The fact that air is an incompressible fluid means that the volume of the air mass will always be constant over time. We must also know that air flows do not separate from each other to form voids, also called gaps.
Many scientists deny that the Coanda effect occurs in water. It is said that this deflection of the water's trajectory when it collides with the surface of a solid body is caused by surface tension. Therefore, it can be said that the Coanda effect does not apply to all types of fluids, since their density and viscosity must also be taken into account. We know that air has a low viscosity. so the Coanda effect occurs with more intensity.
I hope that with this information you can learn more about the Coanda effect and its importance in aviation and motor racing.