NU_VCYL_METHODS

This function returns available ht correlation names for free convection from a vertical cylinder at the specified conditions. It can use optional geometric inputs and optionally restrict methods to valid ranges.

Method filtering is based on standard free-convection dimensionless groups:

Ra = Gr\,Pr

and output is returned as a one-column 2D array for Excel spill compatibility.

Excel Usage

=NU_VCYL_METHODS(Pr, Gr, L, D, check_ranges)

Pr (float, required): Prandtl number of the fluid (dimensionless).
Gr (float, required): Grashof number based on cylinder height (dimensionless).
L (float, optional, default: null): Cylinder length (m).
D (float, optional, default: null): Cylinder diameter (m).
check_ranges (bool, optional, default: true): Whether to filter methods by validity ranges (dimensionless).

Returns (list[list]): Available correlation names as a column list.

Example 1: Vertical cylinder methods default

Inputs:

Pr	Gr
0.72	10000000

Excel formula:

=NU_VCYL_METHODS(0.72, 10000000)

Expected output:

McAdams, Weiss & Saunders
Churchill Vertical Plate
Griffiths, Davis, & Morgan
Jakob, Linke, & Morgan
Carne & Morgan
Eigenson & Morgan
Touloukian & Morgan
Kreith & Eckert
Hanesian, Kalish & Morgan

Example 2: Vertical cylinder methods without range checks

Inputs:

Pr	Gr	check_ranges
0.72	10000000	false

Excel formula:

=NU_VCYL_METHODS(0.72, 10000000, FALSE)

Expected output:

McAdams, Weiss & Saunders
Churchill Vertical Plate
Griffiths, Davis, & Morgan
Jakob, Linke, & Morgan
Carne & Morgan
Eigenson & Morgan
Touloukian & Morgan
Kreith & Eckert
Hanesian, Kalish & Morgan

Example 3: Vertical cylinder methods with geometry inputs

Inputs:

Pr	Gr	L	D
0.7	10000000000	2.5	1

Excel formula:

=NU_VCYL_METHODS(0.7, 10000000000, 2.5, 1)

Expected output:

Popiel & Churchill
Churchill Vertical Plate
Griffiths, Davis, & Morgan
Jakob, Linke, & Morgan
Carne & Morgan
Eigenson & Morgan
Touloukian & Morgan
McAdams, Weiss & Saunders
Kreith & Eckert
Hanesian, Kalish & Morgan
Al-Arabi & Khamis

Example 4: Vertical cylinder methods mid Grashof

Inputs:

Pr	Gr
1.1	5000000

Excel formula:

=NU_VCYL_METHODS(1.1, 5000000)

Expected output:

McAdams, Weiss & Saunders
Churchill Vertical Plate
Griffiths, Davis, & Morgan
Jakob, Linke, & Morgan
Carne & Morgan
Eigenson & Morgan
Touloukian & Morgan
Kreith & Eckert
Hanesian, Kalish & Morgan

Python Code

Show Code

from ht.conv_free_immersed import Nu_vertical_cylinder_methods as ht_Nu_vertical_cylinder_methods

def Nu_vcyl_methods(Pr, Gr, L=None, D=None, check_ranges=True):
    """
    List available correlations for free convection from a vertical cylinder.

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

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

    Args:
        Pr (float): Prandtl number of the fluid (dimensionless).
        Gr (float): Grashof number based on cylinder height (dimensionless).
        L (float, optional): Cylinder length (m). Default is None.
        D (float, optional): Cylinder diameter (m). Default is None.
        check_ranges (bool, optional): Whether to filter methods by validity ranges (dimensionless). Default is True.

    Returns:
        list[list]: Available correlation names as a column list.
    """
    try:
        methods = ht_Nu_vertical_cylinder_methods(Pr, Gr, L=L, D=D, check_ranges=check_ranges)
        if methods is None:
            return "Error: No methods returned"
        return [[method] for method in methods]
    except Exception as e:
        return f"Error: {str(e)}"

Online Calculator

Pr *

Prandtl number of the fluid (dimensionless).

Gr *

Grashof number based on cylinder height (dimensionless).

Cylinder length (m).

Cylinder diameter (m).

check_ranges

Whether to filter methods by validity ranges (dimensionless).