1. What is the Screw Pump Flow Rate Equation?

The screw pump flow rate equation calculates the volumetric flow rate of a screw pump based on its diameter, rotational speed, head, and gravitational acceleration. This simplified version is useful for preliminary calculations in engineering applications.

2. How Does the Calculator Work?

The calculator uses the screw pump flow rate equation:

Where:

• \( Q \) — Flow rate (m³/s)
• \( D \) — Screw diameter (m)
• \( n \) — Rotational speed (rev/s)
• \( H \) — Head or pitch (m)
• \( g \) — Gravitational acceleration (9.81 m/s²)

Explanation: The equation accounts for the geometry of the screw and its rotational speed to determine the volume of fluid displaced per unit time.

3. Importance of Flow Rate Calculation

Details: Accurate flow rate calculation is crucial for pump selection, system design, and ensuring proper operation in applications like wastewater treatment, irrigation, and industrial processes.

4. Using the Calculator

Tips: Enter all values in SI units (meters for length, seconds for time). Diameter and head should be in meters, speed in revolutions per second. Gravity defaults to 9.81 m/s² (Earth's gravity).

5. Frequently Asked Questions (FAQ)

Q1: Is this equation valid for all screw pumps?
A: This is a simplified equation that works well for basic calculations. More complex designs may require additional factors.

Q2: What's a typical flow rate range for screw pumps?
A: Flow rates can vary from 0.001 m³/s for small pumps to over 10 m³/s for large industrial pumps.

Q3: How does viscosity affect the calculation?
A: This simplified equation doesn't account for viscosity. For viscous fluids, actual flow rate may be lower due to friction losses.

Q4: What if my pump has multiple screws?
A: For multiple screws, multiply the result by the number of screws (assuming identical geometry for each).

Q5: How accurate is this calculation?
A: This provides a theoretical maximum. Actual flow may be 5-15% lower due to inefficiencies and slip.