Note:

This calculator determines the percentage lift (H%) of an equal percentage valve based on the relative flow coefficient (Kvr/Kvs) and the valve's rangeability (τ). It essentially translates the flow coefficient ratio into the corresponding valve opening percentage.

Parameters:

• H% (Percentage Lift): The percentage of the valve's full opening, indicating how much the valve is open.
• ln (Natural Logarithm): A mathematical function that helps relate exponential changes in flow coefficient to linear changes in valve lift.
• Kvr (Required capacity at lift 'H'): The flow coefficient required at a specific lift, measured in cubic meters per hour bar (m³/h bar).
• Kvs (Valve capacity full open): The flow coefficient of the valve when fully open, also measured in m³/h bar.
• τ (Valve Rangeability): The ratio of the maximum controllable flow coefficient to the minimum controllable flow coefficient. It indicates the range over which the valve can effectively regulate flow.

Real-life applications:

• Process Control: In chemical plants, refineries, and manufacturing, it helps control the flow of liquids and gases in pipelines.
• HVAC Systems: In heating, ventilation, and air conditioning, it regulates airflow to maintain desired temperatures.
• Water Treatment: In water and wastewater treatment plants, it controls the flow of water and chemicals.

Important:

Please note that Kvr, Kvs, and τ must be greater than zero. Zeros are not accepted as inputs because they would result in undefined or illogical calculations.

Conclusion:

This formula provides a way to determine the valve lift required to achieve a specific flow coefficient, ensuring accurate and efficient flow control in various industrial applications.