Name: wind load check for a facade disc
Uploaded: 2025-03-26T15:00:32.000Z
Duration: 1 min 17 s
Channel: JoVE

K12 Standards

Louisiana Student Standards for Science

High School

Chemistry

Energy

HS-PS3-3

design-example-calculating-safe-diameter-for-wind-exposed-disc

Design Example: Calculating Safe Diameter for Wind-Exposed Disc

A circular disc, 4 meters in diameter, is to be installed on a building as an aesthetic feature.&nbsp; The disc has to face wind with a density of 1.25 kilograms per cubic meter and a velocity of 25 m/s, perpendicular to its surface, with a drag coefficient of 1.1. The disc has to be held securely on a wall-mounted projection capable of providing a reaction force of 3250 Newtons. All other design parameters are assumed safe. For safety, the engineer must ensure the drag force on the disc is less than the reaction force provided by the wall member. Upon calculating the drag force on the disc, it was found to exceed the reaction force that the wall member can withstand, indicating an unsafe condition. The engineer begins by equating the drag force to the reaction force to calculate the required area of the disc, ensuring the drag force does not exceed the wall member's capacity. Finally, the engineer decided to reduce the disc's diameter to 3 meters to ensure safety before installation.

design example: calculating safe diameter for wind-exposed disc

Assessing safety in wind-exposed installations is crucial to preventing potential failures. This example explores the calculation and design adjustments needed to mount a circular disc on a building facade, where wind forces are a primary concern. A 4-meter diameter disc was initially designed as an aesthetic feature facing winds at a velocity of 25 meters per second, with an air density of 1.25 kilograms per cubic meter. Given these conditions, the drag force on the disc was determined using the drag coefficient of 1.1, which measures the resistance an object experiences in a fluid such as air.When calculated, the drag force exceeded the reaction force capacity of 3,250 Newtons that the wall mounting could safely handle, indicating a potential failure risk. Since drag force is directly related to the disc's surface area, which increases with the square of the diameter, the engineer focused on reducing the disc size to lower the drag force. By recalculating, it was determined that a reduced diameter of 3 meters safely brought the drag force within the wall member's capacity. This example demonstrates the critical role of structural adjustments in ensuring safe designs, particularly in wind-exposed installations, where external forces must be carefully balanced with material and structural limitations.

Assessing safety in wind-exposed installations is crucial to preventing potential failures. This example explores the calculation and design adjustments ...

Education

JoVE Core

Civil Engineering

Unit 1

Flow over Immersed Bodies

KEY TERMS AND CONCEPTS

wind load check for a facade disc

Wind load check for a facade disc shows how engineers test whether a mounted shape can stay safe in strong air flow. In this example, a circular disc on a building facade faced wind at 25 meters per second. The air density was 1.25 kilograms per cubic meter, and the disc diameter was first set at 4 meters.

The drag force on the disc was calculated using a drag coefficient of 1.1. The drag coefficient describes how much resistance an object experiences in a fluid such as air. The result was greater than the wall mounting’s safe reaction force capacity of 3,250 Newtons, so the design would have risked failure.

To reduce the load, the engineer changed the disc size instead of the wall member. Drag force depends on surface area, and surface area increases with the square of the diameter. After recalculating, a 3-meter diameter kept the drag force within the mounting limit. This example shows how small design changes can improve safety for wind-exposed installations.

Wind Load Check for a Facade Disc

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drag

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Drag is the resistive force that slows an object moving through a fluid. It comes from pressure acting on the surface and from shear forces along the surface. To calculate drag accurately, scientists often use pressure and wall shear stress distributions from Computational Fluid Dynamics (CFD) or wind tunnel tests. The drag coefficient is a dimensionless number that helps compare drag across different cases. It depends on shape, Reynolds number, Mach number, Froude number, and surface...

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Wind load check for a facade disc shows how engineers test whether a mounted shape can stay safe in strong air flow. In this example, a circular disc on a building facade faced wind at 25 meters per second. The air density was 1.25 kilograms per cubic meter, and the disc diameter was first set at 4 meters. The drag force on the disc was calculated using a drag coefficient of 1.1. The drag coefficient describes how much resistance an object experiences in a fluid such as air. The result was...

key terms and concepts

See how wind force, drag coefficient, and disc diameter affect facade safety, and how reducing the diameter from 4 m to 3 m keeps the load within limits.

Wind Load Check for a Facade Disc | JoVE K12

JoVE Core Civil Engineering offers a foundational exploration of essential construction materials such as bricks, stones, steel, wood, and concrete, along with fluid mechanics topics like flow over immersed bodies, open channel flow, and dimensional modeling. It also covers key surveying concepts, including leveling, traverse adjustments, curve design, topographic mapping, and geospatial technologies (GPS & GIS). Science-in-action videos showcase laboratory research on materials, fluids, and surveying practices in real-world engineering systems.

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HS-PS3-6

Wind Load Check for a Facade Disc

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