Het principe van Bernoulli

Bernoulli's equation applies to any incompressible fluid in a laminar, steady flow. A static fluid has zero kinetic energy density. Thus, Bernoulli's equation applied to a static, incompressible fluid reduces to an expression relating the pressures at different heights.

If a fluid moves horizontally, the gravitational energy density is constant at all points. In this case, Bernoulli's equation relates the pressure at any two points on the streamline with the fluid's speed at those points. This simplified equation is called Bernoulli's principle.

A fluid's passage through a region with high speed reduces its pressure. If another fluid can access this region, it will rush in. This process is called entrainment and has many applications.

For instance, Bunsen burners use natural gases to entrain air for combustion, and atomizers use air to entrain perfume droplets.