Water Pump Horsepower Calculator

Water Horsepower Formula:

\[ WHP = \frac{Q \times H \times SG}{3960} \]

Water Horsepower (WHP):

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1. What is Water Pump Horsepower?

Water Horsepower (WHP) is the theoretical power required to move water based on flow rate, head, and fluid properties. It represents the actual hydraulic power delivered to the fluid by the pump.

2. How Does the Calculator Work?

The calculator uses the Water Horsepower formula:

\[ WHP = \frac{Q \times H \times SG}{3960} \]

Where:

\( WHP \) — Water Horsepower (hp)
\( Q \) — Flow Rate (GPM)
\( H \) — Head (ft)
\( SG \) — Specific Gravity (unitless)
3960 — Conversion constant

Explanation: This formula calculates the hydraulic power required to move water through a pump system, accounting for flow rate, pressure head, and fluid density.

3. Importance of WHP Calculation

Details: Accurate WHP calculation is essential for proper pump selection, energy efficiency analysis, system design, and determining brake horsepower requirements for motor sizing.

4. Using the Calculator

Tips: Enter flow rate in gallons per minute (GPM), head in feet (ft), and specific gravity (1.0 for water). All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is the difference between WHP and BHP?
A: WHP is the hydraulic power delivered to the fluid, while BHP (Brake Horsepower) is the power input to the pump shaft. BHP accounts for pump efficiency losses.

Q2: What is specific gravity and when should I change it?
A: Specific gravity is the ratio of fluid density to water density. Use 1.0 for water. Change it for other fluids like brine (1.2), oil (0.8-0.9), or chemicals.

Q3: Why is the conversion constant 3960?
A: 3960 combines unit conversions: 1 hp = 550 ft-lb/s, 1 GPM = 8.0208 ft³/hr, and time conversions to maintain dimensional consistency.

Q4: Can this calculator be used for other fluids?
A: Yes, for any Newtonian fluid by adjusting the specific gravity value to match the fluid's density relative to water.

Q5: How does head affect horsepower requirements?
A: Horsepower increases linearly with head. Doubling the head doubles the horsepower requirement, assuming constant flow rate and specific gravity.