How to Calculate Wind Load on a Large Flat Surface

How to Calculate Wind Load on a Large Flat Surface
••• PhotoAllel/iStock/GettyImages

Pressure is defined as force per unit area. This force has units of pounds and uses the simplified formula of F = P x A where P is the pressure and A is the surface area. Therefore, the larger the surface area, the larger force it will experience. This is the principle behind why sailing ships use such large sails and why hurricanes easily remove house roofs.

    Determine the surface area exposed to the wind. Assume there is a billboard that has the dimensions of 20 feet by 40 feet. The surface area is length multiplied by width or 20 times 40, which is 800 square feet.

    Determine the wind speed or wind velocity measured in miles per hour. Assume a hurricane has sustained winds of 100 miles per hour (arbitrary value). Air has a density of 0.075 pounds per cubic foot.

    Determine the force of the wind load on the billboard. This is done using the formula F = 1/2 rho x v^2 x A x C where F is the force of the wind load in pounds, rho is the air density, v is the wind velocity, A is the surface area of the billboard and C is a dimensionless drag coefficient (assumed to be 1.0). The calculation yields 1/2 x 0.075 x 100^2 x 800 x 1.0 or 300,000 pounds of force which is substantial.

Related Articles

How to Calculate Wind Loads From Wind Speeds
How to Calculate Lift for Rotor Blades
How to Find Mass in Weight
Why Is the Anemometer Important to Weather Forecasting?
How to Calculate Buoy Floatation in the Water
The Four Forces That Influence Wind Speed & Wind Direction
How to Calculate Hydraulic Cylinder Tonnage
How to Calculate Hydraulic System Pressure
How to Calculate Shear Area
How to Convert Seconds Into Miles Per Hour
How to Convert Kilopascals to Joules
How to Calculate kPa
How to Calculate a Circular Area
How to Calculate Pendulum Force
How to Calculate Hydraulic Press Force in Tons
How to Tell if an Object Will Sink or Float
How Are Winds Formed?
What Units Does the Anemometer Measure In?
How to Convert a Load to PSI in a Tensile Test
How to Calculate the Acreage of a Triangle