Calculate the blowing force of an air jet from air velocity and nozzle diameter or area, or from air pressure, with results in N, lbf and kgf.

Air density and coefficient (optional)
Standard sea-level air at 15 °C is 1.225 kg/m³. Change it for hot, cold or high-altitude air.

1 assumes the air hits a flat surface square-on and stops. Use a known coefficient for angled or partial impact.

Blowing Force Formula

The following equation is used to calculate the Blowing Force.

BF = Da × A × V2
  • Where BF is the blowing force (N)
  • Da is the density of air (kg/m3)
  • A is the contact area (m2)
  • V is the velocity of the air (m/s)

To calculate the blow force, multiply the density of air by the contact area, then multiply by the velocity of the air squared.

What is a Blowing Force?

Definition:

How to Calculate Blowing Force?

Example Problem:

The following example outlines the steps and information needed to calculate Blowing Force.

First, determine the density of air. In this example, the density of air is found to be 1.225 kg/m3.

Next, determine the contact area. For this problem, the contact area is found to be 5 m2.

Next, determine the air velocity. In this case, the air velocity is measured to be 10 m/s.

Finally, calculate the Blowing Force using the formula above:

BF = Da * A * V2

BF = 1.225*5*102

BF = 612.5 N