The Joukowski equation

Surge analysis is an important step in the creation and maintenance of a pipe network, but one that is highly complex. Due to that complexity and the need for specialized analysis tools, many existing guidelines simplify the process.

Limitation of the Joukowski Equation:

Most simple expressions, such as the Joukowski equation, only apply in highly restricted or unrealistic circumstances.

Joukowski Equation (ΔP=ρcΔV)  

For example, two important restrictions must be in place for the Joukowski equation to work:

• There should be only a small head loss resulting from friction.
• There should be no wave reflections from any hydraulic devices or boundary conditions in the system.

If conditions are not met, Joukowski equation ceases to be valid, and any conclusions based on it may not be applicable.

Also, Joukowski equation does not consider liquid column separation, or cavitation.

When Modeling Transients:

No simplified rules can provide a prediction of worst-case performance under all transient conditions.

Surge response in water distribution systems is sensitive to system-specific characteristics.

Careless generalization and simplification could lead to incorrect results and inadequate surge protection.

InfoSurge Pro is capable of comprehensive surge analysis.

This approach is both justified by its importance and practical, owing to the rapid development of faster computers and efficient numerical simulation models.