Pressure Washer Nozzle Calculator

Flow Rate Formula:

\[ Q = C_d \times A \times \sqrt{\frac{2 \times \Delta P}{\rho}} \times 448.83 \]

Discharge Coefficient (C_d):

Nozzle Area (A):

ft²

Pressure Difference (ΔP):

psi

Fluid Density (ρ):

lb/ft³

Flow Rate (GPM):

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1. What is a Pressure Washer Nozzle Calculator?

Definition: This calculator estimates the flow rate (in gallons per minute) through a pressure washer nozzle based on fluid dynamics principles.

Purpose: It helps professionals and homeowners determine the expected flow rate for their pressure washing equipment, which affects cleaning performance.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ Q = C_d \times A \times \sqrt{\frac{2 \times \Delta P}{\rho}} \times 448.83 \]

Where:

\( Q \) — Flow rate (gallons per minute)
\( C_d \) — Discharge coefficient (dimensionless, typically 0.7-0.9)
\( A \) — Nozzle area (square feet)
\( \Delta P \) — Pressure difference (psi)
\( \rho \) — Fluid density (lb/ft³, 62.4 for water)

Explanation: The formula calculates theoretical flow rate adjusted by the discharge coefficient to account for real-world nozzle efficiency.

3. Importance of Flow Rate Calculation

Details: Proper flow rate estimation ensures optimal cleaning performance, prevents pump damage, and helps select appropriate nozzle sizes.

4. Using the Calculator

Tips: Enter the discharge coefficient (default 0.8), nozzle area in square feet, pressure difference in psi, and fluid density (default 62.4 lb/ft³ for water). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical discharge coefficient for pressure washer nozzles?
A: Most pressure washer nozzles have C_d values between 0.7 and 0.9, with 0.8 being a good average.

Q2: How do I calculate nozzle area?
A: For circular nozzles, area = π × (diameter/2)². Convert diameter from inches to feet (divide by 12) before squaring.

Q3: Why does fluid density matter?
A: Denser fluids flow more slowly under the same pressure. The default value (62.4) is for water at standard conditions.

Q4: What's the relationship between flow rate and pressure?
A: Flow rate increases with the square root of pressure, meaning quadrupling pressure only doubles flow rate.

Q5: How does nozzle size affect cleaning?
A: Smaller nozzles increase pressure but reduce flow rate, while larger nozzles increase flow rate but reduce pressure.