Kinetic energy correction factor

From Chemepedia

The kinetic energy correction factor results from equating

            (1)

in order to simplify the energy balance or the mechanical energy balance.

For fully-developed laminar flow in pipes, the kinetic energy correction factor is 0.5 as seen in equation (2). For fully-developed turbulent pipe flow, the correction factor ranges ranges from 0.9 and 0.96. In elementary analysis, the kinetic energy correction factors are often ignored (i.e., is set equal to 1) as most flows encountered in practice are turbulent.


            (2)

Turbulent Flow

The presence of turbulent flow introduces complexities to the kinetic energy correction factor, and as such a relationship is needed to define the relationship between v and position.


            (3)


By substituting equation (3), the approximate velocity profile, into the and equations, the kinetic energy correction factor can be solved for. After integrating and solving, the correction factor comes out to approximately 0.9448, commonly rounded to 0.95.

The equation


            (4)

References

Geankoplis, Christie J. Transport Processes and Separation Process Principles (Includes Unit Operations). Prentice Hall, 2007.