HEL_TURB_NU_MORI

This function computes the turbulent-flow Nusselt number for a helical coil using the Mori–Nakayama correlation. It uses Reynolds number, Prandtl number, and coil geometry to estimate dimensionless internal convection performance for curved-tube flow.

Excel Usage

=HEL_TURB_NU_MORI(Re, Pr, Di, Dc)

Re (float, required): Reynolds number based on tube diameter (-).
Pr (float, required): Prandtl number (-).
Di (float, required): Inner tube diameter (m).
Dc (float, required): Coil diameter (m).

Returns (float): Nusselt number for turbulent flow in a helical coil (-).

Example 1: Mori-Nakayama example

Inputs:

Re	Pr	Di	Dc
200000	0.7	0.01	0.2

Excel formula:

=HEL_TURB_NU_MORI(200000, 0.7, 0.01, 0.2)

Expected output:

496.252

Example 2: Moderate Reynolds number

Inputs:

Re	Pr	Di	Dc
150000	1.2	0.008	0.15

Excel formula:

=HEL_TURB_NU_MORI(150000, 1.2, 0.008, 0.15)

Expected output:

434.88

Example 3: High Reynolds number

Inputs:

Re	Pr	Di	Dc
500000	0.9	0.012	0.25

Excel formula:

=HEL_TURB_NU_MORI(500000, 0.9, 0.012, 0.25)

Expected output:

1096.32

Example 4: Lower Reynolds number

Inputs:

Re	Pr	Di	Dc
80000	2	0.006	0.1

Excel formula:

=HEL_TURB_NU_MORI(80000, 2, 0.006, 0.1)

Expected output:

319.563

Python Code

Show Code

from ht.conv_internal import helical_turbulent_Nu_Mori_Nakayama as ht_helical_turbulent_Nu_Mori_Nakayama

def hel_turb_nu_mori(Re, Pr, Di, Dc):
    """
    Calculate the turbulent helical coil Nusselt number using Mori-Nakayama.

    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 based on tube diameter (-).
        Pr (float): Prandtl number (-).
        Di (float): Inner tube diameter (m).
        Dc (float): Coil diameter (m).

    Returns:
        float: Nusselt number for turbulent flow in a helical coil (-).
    """
    try:
        return ht_helical_turbulent_Nu_Mori_Nakayama(Re=Re, Pr=Pr, Di=Di, Dc=Dc)
    except Exception as e:
        return f"Error: {str(e)}"

Online Calculator

Re *

Reynolds number based on tube diameter (-).

Pr *

Prandtl number (-).

Di *

Inner tube diameter (m).

Dc *

Coil diameter (m).