Flow Ratio Calculator

Flow Ratio Formula:

\[ K_f = \frac{V_{f2}}{\sqrt{2 \cdot [g] \cdot H_m}} \]

Flow Ratio (Kf):

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is Flow Ratio?

Flow ratio in centrifugal pumps is the ratio of the actual flow velocity at the outlet to the theoretical velocity of the jet corresponding to the manometric head. It's an important parameter for evaluating pump performance and efficiency.

2. How Does the Calculator Work?

The calculator uses the flow ratio formula:

\[ K_f = \frac{V_{f2}}{\sqrt{2 \cdot [g] \cdot H_m}} \]

Where:

\( K_f \) — Flow ratio (dimensionless)
\( V_{f2} \) — Flow velocity at outlet of centrifugal pump (m/s)
\( [g] \) — Gravitational acceleration constant (9.80665 m/s²)
\( H_m \) — Manometric head of centrifugal pump (m)

Explanation: This formula calculates the ratio between the actual outlet velocity and the theoretical maximum velocity that would be achieved under ideal conditions with the given manometric head.

3. Importance of Flow Ratio Calculation

Details: Flow ratio is crucial for assessing centrifugal pump performance, optimizing efficiency, and ensuring proper pump selection for specific applications. It helps in understanding how closely the pump operates to its theoretical maximum performance.

4. Using the Calculator

Tips: Enter flow velocity at outlet in m/s and manometric head in meters. Both values must be positive numbers greater than zero for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical range for flow ratio in centrifugal pumps?
A: Flow ratio typically ranges from 0.1 to 0.3 for most centrifugal pumps, with optimal values around 0.2-0.25 for maximum efficiency.

Q2: How does flow ratio affect pump efficiency?
A: Higher flow ratios generally indicate better pump performance, but extremely high values may suggest cavitation or other operational issues.

Q3: Can flow ratio be greater than 1?
A: Typically no, as it represents the ratio of actual velocity to theoretical maximum velocity. Values approaching 1 would indicate nearly ideal performance.

Q4: What factors influence flow ratio?
A: Impeller design, pump speed, fluid properties, and system resistance all affect the flow ratio value.

Q5: How often should flow ratio be calculated for pump maintenance?
A: Regular monitoring of flow ratio during routine maintenance helps identify performance degradation and schedule timely interventions.