1. What is the Length of Weir Formula?

The Length of Weir formula calculates the required length of a broad-crested weir to handle a specific discharge rate, considering the coefficient of discharge and arc length of the circular weir opening.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( L_w \) — Length of Weir (m)
• \( Q \) — Discharge Weir (m³/s)
• \( C_d \) — Coefficient of Discharge
• \( l_a \) — Arc Length of Circle (m)

Explanation: The formula determines the necessary weir length based on the discharge rate, discharge coefficient, and the arc length of the circular weir opening.

3. Importance of Weir Length Calculation

Details: Accurate weir length calculation is crucial for proper hydraulic design, ensuring efficient water flow control, and preventing overflow or underflow conditions in water management systems.

4. Using the Calculator

Tips: Enter discharge in m³/s, coefficient of discharge (typically between 0.6-0.9), and arc length in meters. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is a broad-crested weir?
A: A broad-crested weir is a hydraulic structure with a wide crest used for flow measurement and control in open channels.

Q2: What is the typical range for coefficient of discharge?
A: The coefficient of discharge for broad-crested weirs typically ranges from 0.6 to 0.9, depending on the weir geometry and flow conditions.

Q3: How does arc length affect weir performance?
A: The arc length determines the flow area and directly influences the discharge capacity of the weir.

Q4: When is this formula most applicable?
A: This formula is specifically designed for broad-crested weirs with circular openings and should be used within its validated range.

Q5: What factors can affect the accuracy of calculations?
A: Factors include weir geometry, approach velocity, water temperature, and the accuracy of input parameters.