Enter the total dynamic pressure and the fluid mass density into the calculator to determine the velocity. This calculator can also evaluate the pressure or density given the other variables are known.

Pressure to Velocity Formula

The following formula is used to calculate a velocity from dynamic pressure. 

V = Sqrt [ (2*q/p) ]
  • Where V is the velocity (m/s)
  • q is the dynamic pressure (pascals)
  • p is the fluid mass density (kg/m^3)

To calculate velocity from pressure, multiply the dynamic pressure by 2, divide by the fluid mass density, then take the square root of that result.

Pressure to Velocity Definition

Calculating a velocity from a dynamic pressure requires that you also know the density. Dynamic pressure arises from the movement of fluid through a volume.

Pressure to Velocity Example

How to calculate velocity from pressure?

The first step in calculating a velocity from pressure is to determine or measure the dynamic pressure that happens as a result of the fluid flow through the pipe.

In this example, the dynamic pressure is found to be 200 pascals.

The next step is to determine the density of the fluid. In this case, the density is measured to be 1.225 kg/m^3.

Finally, calculate the velocity from the dynamic pressure and density using the formula above:

V = Sqrt [ (2*q/p) ]

V = Sqrt [ (2*200/1.225) ]

V = 18.07 m/s.

FAQ

What is dynamic pressure?

Dynamic pressures are pressure differentials that arise from the flow of a fluid through a constrained area.

What is the relationship between pressure and velocity in fluid dynamics?

Bernoulli’s equation describes the relationship between pressure and velocity in fluid dynamics.

It states that in a fluid flowing through a pipe or channel, an increase in the velocity of the fluid will result in a decrease in pressure, and vice versa.

How does pressure change with velocity in a fluid?

In a fluid, pressure and velocity are inversely proportional to each other.

As the velocity of the fluid increases, the pressure decreases, and as the velocity decreases, the pressure increases.

What is Bernoulli’s equation used for?

Bernoulli’s equation describes the relationship between pressure, velocity, and height in a fluid flow system.

It is commonly used in various fields such as aerodynamics, hydrodynamics, and mechanics to analyze the flow of fluids.

Why does the pressure decrease with velocity in a fluid flow?

The pressure decreases with velocity in a fluid flow due to energy conservation.

As the fluid flows and its velocity increases, its pressure decreases to conserve the total energy of the fluid.

What is the difference between dynamic pressure and static pressure?

Dynamic pressure is the pressure that arises due to the motion of a fluid, while static pressure is the pressure exerted by a fluid at rest.

Dynamic pressure is proportional to the square of the velocity of the fluid, while the fluid’s density and height determine static pressure.

How is pressure affected by the velocity of a fluid?

The velocity of a fluid affects pressure by changing the dynamic pressure of the fluid.

An increase in velocity results in an increase in the dynamic pressure, and a decrease in the static pressure.

What is the effect of temperature on the pressure in a fluid?

The temperature affects pressure in a fluid due to its impact on the fluid’s density.

An increase in temperature will increase the fluid’s volume, causing the pressure to decrease.

A decrease in temperature will result in a decrease in the fluid’s volume, causing the pressure to increase.

How does fluid velocity affect the pressure drop in a pipe?

The velocity of a fluid affects the pressure drop in a pipe by changing the dynamic pressure of the fluid. An increase in fluid velocity will result in an increase in the dynamic pressure, causing a more significant pressure drop.

A decrease in fluid velocity will result in a decrease in the dynamic pressure, causing a smaller pressure drop.

How does the viscosity of a fluid affect the relationship between pressure and velocity?

Viscosity affects the relationship between pressure and velocity in a fluid by slowing down the flow of the fluid.

A higher-viscosity fluid will have a lower velocity, resulting in higher pressure, while a lower viscosity fluid will have a higher velocity, resulting in lower pressure.