1. What is the Wind Speed Height Formula?

Definition: This formula calculates wind speed at a certain height based on a reference wind speed and height, accounting for atmospheric boundary layer effects.

Purpose: It's essential for wind energy applications, structural engineering, and environmental studies where wind speed varies with height.

2. How Does the Formula Work?

The formula is:

Where:

• \( v \) — Wind speed at height z (m/s)
• \( v_{ref} \) — Reference wind speed (m/s)
• \( z \) — Height above ground (m)
• \( z_{ref} \) — Reference height (typically 10m) (m)
• \( \alpha \) — Shear exponent (dimensionless)

Explanation: The formula models how wind speed increases with height according to a power law relationship.

3. Importance of Wind Speed Height Calculation

Details: Accurate wind speed estimation at different heights is crucial for wind turbine placement, building design, and pollution dispersion studies.

4. Using the Calculator

Tips: Enter the reference wind speed (m/s), desired height (m), reference height (default 10m), and shear exponent (default 0.14). All values must be > 0 except α which can be 0.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical shear exponent (α) value?
A: Over open terrain (grass, few trees), α ≈ 0.14; over rougher terrain (urban, forest), α ≈ 0.25-0.4.

Q2: Why is 10m the standard reference height?
A: 10m is the standard height for meteorological measurements, providing consistent reference data.

Q3: When would I use a different reference height?
A: When working with data from a different measurement height, or for specific applications like rooftop wind assessments.

Q4: How accurate is this formula?
A: It's a simplified model that works well for engineering purposes but may not capture all atmospheric complexities.

Q5: What are typical reference wind speeds?
A: Average wind speeds vary by location but typically range from 3-8 m/s at 10m height for most land areas.