TURB_GNIELINSKI

This function computes turbulent internal-flow Nusselt number using the Gnielinski correlation. It combines Reynolds number, Prandtl number, and friction factor to provide a widely used general-purpose turbulent pipe heat-transfer estimate.

Excel Usage

=TURB_GNIELINSKI(Re, Pr, fd)

Re (float, required): Reynolds number (-).
Pr (float, required): Prandtl number (-).
fd (float, required): Darcy friction factor (-).

Returns (float): Turbulent Nusselt number for pipe flow (-).

Example 1: Gnielinski example

Inputs:

Re	Pr	fd
100000	1.2	0.0185

Excel formula:

=TURB_GNIELINSKI(100000, 1.2, 0.0185)

Expected output:

254.627

Example 2: Higher Reynolds number

Inputs:

Re	Pr	fd
200000	0.8	0.02

Excel formula:

=TURB_GNIELINSKI(200000, 0.8, 0.02)

Expected output:

436.295

Example 3: Mid Reynolds number

Inputs:

Re	Pr	fd
50000	2	0.022

Excel formula:

=TURB_GNIELINSKI(50000, 2, 0.022)

Expected output:

193.717

Example 4: Lower Reynolds number

Inputs:

Re	Pr	fd
150000	1	0.017

Excel formula:

=TURB_GNIELINSKI(150000, 1, 0.017)

Expected output:

316.625

Python Code

Show Code

from ht.conv_internal import turbulent_Gnielinski as ht_turbulent_Gnielinski

def turb_gnielinski(Re, Pr, fd):
    """
    Calculate turbulent Nusselt number using the Gnielinski correlation.

    See: https://ht.readthedocs.io/en/latest/ht.conv_internal.html

    This example function is provided as-is without any representation of accuracy.

    Args:
        Re (float): Reynolds number (-).
        Pr (float): Prandtl number (-).
        fd (float): Darcy friction factor (-).

    Returns:
        float: Turbulent Nusselt number for pipe flow (-).
    """
    try:
        return ht_turbulent_Gnielinski(Re=Re, Pr=Pr, fd=fd)
    except Exception as e:
        return f"Error: {str(e)}"

Online Calculator

Re *

Reynolds number (-).

Pr *

Prandtl number (-).

fd *

Darcy friction factor (-).