NU_CONV_INT_METHODS

This function returns the available internal-convection method names for a given pipe-flow condition. It can optionally filter to only range-appropriate correlations based on Reynolds number, Prandtl number, roughness, and entry-region inputs.

Excel Usage

=NU_CONV_INT_METHODS(Re, Pr, eD, Di, x, fd, check_ranges)

Re (float, required): Reynolds number (-).
Pr (float, required): Prandtl number (-).
eD (float, optional, default: 0): Relative roughness (-).
Di (float, optional, default: null): Inside diameter of the pipe (m).
x (float, optional, default: null): Axial distance from the inlet (m).
fd (float, optional, default: null): Darcy friction factor (-).
check_ranges (bool, optional, default: true): Whether to return only applicable correlations (-).

Returns (list[list]): 2D array of available correlation method names.

Example 1: Methods for turbulent flow

Inputs:

Re	Pr
100000	0.7

Excel formula:

=NU_CONV_INT_METHODS(100000, 0.7)

Expected output:

Churchill-Zajic
Petukhov-Kirillov-Popov
Gnielinski
Bhatti-Shah
Dipprey-Sabersky
Sandall
Webb
Friend-Metzner
Prandtl
von-Karman
Gowen-Smith
Kawase-Ulbrecht
Kawase-De
Nunner
Dittus-Boelter
Sieder-Tate
Drexel-McAdams
Colburn
ESDU
Gnielinski smooth low Pr
Gnielinski smooth high Pr

Example 2: Methods for laminar entry flow

Inputs:

Re	Pr	x	Di
100	0.7	0.01	0.1

Excel formula:

=NU_CONV_INT_METHODS(100, 0.7, 0.01, 0.1)

Expected output:

Baehr-Stephan laminar thermal/velocity entry
Hausen laminar thermal entry
Seider-Tate laminar thermal entry
Laminar - constant T
Laminar - constant Q

Example 3: Methods for rough pipe

Inputs:

Re	Pr	eD
50000	2	0.001

Excel formula:

=NU_CONV_INT_METHODS(50000, 2, 0.001)

Expected output:

Churchill-Zajic
Petukhov-Kirillov-Popov
Gnielinski
Bhatti-Shah
Dipprey-Sabersky
Sandall
Webb
Friend-Metzner
Prandtl
von-Karman
Gowen-Smith
Kawase-Ulbrecht
Kawase-De
Nunner
Dittus-Boelter
Sieder-Tate
Drexel-McAdams
Colburn
ESDU
Gnielinski smooth low Pr
Gnielinski smooth high Pr

Example 4: Methods without range checking

Inputs:

Re	Pr	check_ranges
200000	1	false

Excel formula:

=NU_CONV_INT_METHODS(200000, 1, FALSE)

Expected output:

Laminar - constant T
Laminar - constant Q
Martinelli
Hausen
Churchill-Zajic
Petukhov-Kirillov-Popov
Gnielinski
Bhatti-Shah
Dipprey-Sabersky
Sandall
Webb
Friend-Metzner
Prandtl
von-Karman
Gowen-Smith
Kawase-Ulbrecht
Kawase-De
Nunner
Dittus-Boelter
Sieder-Tate
Drexel-McAdams
Colburn
ESDU
Gnielinski smooth low Pr
Gnielinski smooth high Pr

Python Code

Show Code

from ht.conv_internal import Nu_conv_internal_methods as ht_Nu_conv_internal_methods

def nu_conv_int_methods(Re, Pr, eD=0, Di=None, x=None, fd=None, check_ranges=True):
    """
    List available internal convection correlations for a pipe.

    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 (-).
        eD (float, optional): Relative roughness (-). Default is 0.
        Di (float, optional): Inside diameter of the pipe (m). Default is None.
        x (float, optional): Axial distance from the inlet (m). Default is None.
        fd (float, optional): Darcy friction factor (-). Default is None.
        check_ranges (bool, optional): Whether to return only applicable correlations (-). Default is True.

    Returns:
        list[list]: 2D array of available correlation method names.
    """
    try:
        methods = ht_Nu_conv_internal_methods(
            Re=Re,
            Pr=Pr,
            eD=eD,
            Di=Di,
            x=x,
            fd=fd,
            check_ranges=check_ranges,
        )
        return [[method] for method in methods]
    except Exception as e:
        return f"Error: {str(e)}"

Online Calculator

Re *

Reynolds number (-).

Pr *

Prandtl number (-).

Relative roughness (-).

Inside diameter of the pipe (m).

Axial distance from the inlet (m).

Darcy friction factor (-).

check_ranges

Whether to return only applicable correlations (-).