What Is the Cipolletti Trapezoidal Weir Discharge Calculator?
The Cipolletti weir is a contracted trapezoidal open channel weir whose side slopes flare at 1 horizontal to 4 vertical (approx 14.04° from vertical).
This specific trapezoidal flare geometrically offsets the discharge reduction caused by end contractions on rectangular weirs, simplifying discharge calculations to Q = Cd · b · h^(1.5).
This calculator computes volumetric discharge rate in m³/s and L/s, effective flow area, average crest approach velocity, and verifies head-to-crest ratio limits.
How Does the Cipolletti Trapezoidal Weir Discharge Calculator Work?
The calculation evaluates user-provided measurements using recognized domain equations, converts between measurement units, and adjusts for real-world efficiency factors.
Cipolletti Trapezoidal Weir Discharge Calculator Formula & Variables
The core mathematical equation utilized by this calculator is expressed as:
Cipolletti trapezoidal weir discharge formula where end flaring compensates exactly for crest side contractions.
How to Use the Cipolletti Trapezoidal Weir Discharge Calculator
- Enter your primary measurements in the input fields above.
- Select your preferred units (e.g. metric or imperial) if applicable.
- Review or adjust operational assumptions such as field efficiency.
- Click Calculate to instantly generate the full results breakdown and visual chart.
- Use the Reset button at any time to clear the form and test a new scenario.
Step-by-Step Example Calculation
Irrigation Canal Gauging (b = 2.5m, h = 0.45m)
Input Values:
Understanding Your Result
Your calculated result represents the realistic operational capacity or baseline output under the specified conditions. Comparing theoretical and effective outputs reveals the direct impact of turns, overlap, and practical downtime.
Factors That Affect the Result
Field terrain, operator experience, equipment maintenance, overlap margin, and weather conditions can significantly influence real-world output.
When Should You Use This Calculator?
Use this calculator whenever you need quick, verified estimates for job planning, budgeting, equipment sizing, or project timelines.
Assumptions & Limitations
- Head h should be measured upstream of the weir at a distance of at least 4·h to avoid draw-down curvature.
- Head-to-crest length ratio h/b should ideally remain below 0.33 for standard accuracy.
Frequently Asked Questions
Calculation Accuracy & Reference Note
This calculator implements verified, deterministic mathematical equations based on published standards. Results should be treated as professional engineering estimates; always verify critical operations with local equipment manuals and site inspections.