Radius of Pipe by Hazen Williams Formula given Length of Pipe Calculator

Hazen Williams Formula:

\[ R = \left( \frac{6.78 \times L_p \times v_{avg}^{1.85}}{2^{1.165} \times h_f \times C^{1.85}} \right)^{1/1.165} \]

Length of Pipe:

Average Velocity in Pipe Fluid Flow:

m/s

Head Loss:

Coefficient of Roughness of Pipe:

Pipe Radius:

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1. What is the Hazen Williams Formula?

The Hazen Williams formula is an empirical relationship used in fluid mechanics to calculate the head loss or flow rate in water piping systems. It's particularly useful for water distribution system design and analysis.

2. How Does the Calculator Work?

The calculator uses the Hazen Williams formula rearranged to solve for pipe radius:

\[ R = \left( \frac{6.78 \times L_p \times v_{avg}^{1.85}}{2^{1.165} \times h_f \times C^{1.85}} \right)^{1/1.165} \]

Where:

\( R \) — Pipe Radius (m)
\( L_p \) — Length of Pipe (m)
\( v_{avg} \) — Average Velocity in Pipe Fluid Flow (m/s)
\( h_f \) — Head Loss (m)
\( C \) — Coefficient of Roughness of Pipe (dimensionless)

Explanation: The formula calculates the required pipe radius based on given flow conditions and head loss constraints.

3. Importance of Pipe Radius Calculation

Details: Accurate pipe radius calculation is crucial for designing efficient fluid transport systems, ensuring adequate flow rates while minimizing energy losses and construction costs.

4. Using the Calculator

Tips: Enter all values in consistent units (meters for length measurements). The coefficient of roughness typically ranges from 130-150 for new pipes and decreases with age and corrosion.

5. Frequently Asked Questions (FAQ)

Q1: What is the typical range for the roughness coefficient C?
A: For water pipes, C values typically range from 130-150 for new pipes, 100-140 for older pipes, and can be as low as 40-80 for severely corroded pipes.

Q2: When is the Hazen Williams formula most applicable?
A: The formula is most accurate for water flow in pipes with diameters between 50-3500 mm and velocities between 0.3-3 m/s.

Q3: What are the limitations of the Hazen Williams formula?
A: The formula is empirical and less accurate for fluids other than water, for very high or low temperatures, or for non-turbulent flow conditions.

Q4: How does pipe material affect the roughness coefficient?
A: Different materials have different inherent roughness. For example, PVC pipes typically have C=150, while cast iron pipes may have C=100-130 depending on age and condition.

Q5: Can this formula be used for pressurized gas systems?
A: The Hazen Williams formula is primarily designed for water systems. For gas systems, other formulas like Weymouth or Panhandle equations are more appropriate.