Why is the air flow faster and the pressure smaller?

Dear Yi, if you pursue it too much, you will only get more and more incomprehensible.

The flow velocity causes a pressure difference between the front and back of the flowing liquid or gas, and the pressure difference in the front is greater than in the back due to the action of inertia, or the continuous action of pushing behind. In this way, the flow rate in the front is greater than that in the back, so that the liquid or gas behind is in short supply. The supply exceeds the demand, so that the liquid or gas on both sides come to fill the gap, and the tendency to fill the gap will reduce the pressure on both sides.

This led to the common experiment of blowing air in the middle of two sheets of paper, and the two sheets of paper would run together.

The greater the flow velocity, the smaller the pressure, which is described below

The greater the fluid velocity, the lower the pressure, which is derived from the law of conservation of energy according to Bernoulli's equation.

Daniel Bernoulli proposed the "Bernoulli Principle" in 1726. This is the basic principle adopted by hydraulics before the establishment of the theoretical equations of continuum in fluid mechanics, the essence of which is the conservation of mechanical energy of fluids. Namely:

Kinetic energy + gravitational potential energy + pressure potential energy = constant. The most famous corollary is that when the flow is at a constant height, the flow velocity is high, and the pressure is small.

Bernoulli's principle is often expressed as p+1 2pv2+pgh=c, and this formula is called Bernoulli's equation. where p is the pressure at a point in the fluid, v is the velocity of the fluid at that point, p is the density of the fluid, g is the acceleration due to gravity, h is the height of the point, and c is a constant. It can also be expressed as p1+1 2pv12+pgh1=p2+1 2pv22+pgh2.

Expand your knowledge: Bernoulli's equation:

Bernoulli's equation is a dynamic equation for the steady flow of an ideal fluid, which means that the sum of the pressure potential energy, kinetic energy and potential energy at any two points on the streamline remains unchanged in the flow of the fluid ignoring viscous loss. This theory was proposed by the Swiss mathematician Daniel Bernoulli in 1738 and was then known as Bernoulli's principle.

Later generations called the integral of Euler's equation along the streamline in the gravitational field when it flows steadily as the Bernoulli integral, and the energy equation of the steady adiabatic flow of non-viscous fluid in the gravitational field as the Bernoulli auriana theorem. These are collectively known as Bernoulli's equations, which are one of the fundamental equations of fluid dynamics and mechanics.

Bernoulli's equation is essentially the manifestation of the law of conservation of energy in the steady flow of an ideal fluid, which is the fundamental law of fluid mechanics. The conservation of mechanical energy at the point of flow on a streamline is the physical meaning of Bernoulli's equation.

Application points: The general methods of applying Bernoulli's equation to solve practical problems can be summarized as follows:

1.Select the appropriate datum level first;

2.Two calculated cross-sections, one on the cross-section of the requested parameters and the other on the cross-section of the known parameters;

3.The Bernoulli equation is listed in terms of the direction in which the liquid flows.