H_NUCLEIC

This function is a unified nucleate-boiling interface that selects or applies a specific pool-boiling correlation based on provided inputs and optional method choice.

It evaluates a method-specific model of the form:

h = f(\text{thermophysical properties},\; P,\; P_c,\; q\ \text{or}\ \Delta T_e)

The function supports multiple established correlations and exposes key method parameters such as roughness, contact angle, and material properties.

Excel Usage

=H_NUCLEIC(Te, q, Tsat, P, dPsat, Cpl, kl, mul, rhol, sigma, Hvap, rhog, MW, Pc, Csf, n, kw, rhow, Cpw, angle, Rp, Ra, h_ref, CAS, h_nucleic_method)

Te (float, optional, default: null): Excess wall temperature (K).
q (float, optional, default: null): Heat flux (W/m^2).
Tsat (float, optional, default: null): Saturation temperature at operating pressure (K).
P (float, optional, default: null): Saturation pressure of fluid (Pa).
dPsat (float, optional, default: null): Saturation pressure difference at excess temperature (Pa).
Cpl (float, optional, default: null): Heat capacity of liquid (J/kg/K).
kl (float, optional, default: null): Thermal conductivity of liquid (W/m/K).
mul (float, optional, default: null): Viscosity of liquid (Pa*s).
rhol (float, optional, default: null): Density of the liquid (kg/m^3).
sigma (float, optional, default: null): Surface tension of liquid (N/m).
Hvap (float, optional, default: null): Heat of vaporization of the fluid (J/kg).
rhog (float, optional, default: null): Density of the produced gas (kg/m^3).
MW (float, optional, default: null): Molecular weight of fluid (g/mol).
Pc (float, optional, default: null): Critical pressure of fluid (Pa).
Csf (float, optional, default: 0.013): Rohsenow coefficient specific to fluid and metal (-).
n (float, optional, default: 1.7): Rohsenow constant (-).
kw (float, optional, default: 401): Thermal conductivity of wall material (W/m/K).
rhow (float, optional, default: 8.96): Density of wall material (kg/m^3).
Cpw (float, optional, default: 384): Heat capacity of wall material (J/kg/K).
angle (float, optional, default: 35): Contact angle of bubble with wall (degrees).
Rp (float, optional, default: 0.000001): Surface roughness parameter for the Cooper method (m).
Ra (float, optional, default: 4e-7): Roughness parameter for the Gorenflo method (m).
h_ref (float, optional, default: null): Reference heat transfer coefficient for Gorenflo (W/m^2/K).
CAS (str, optional, default: null): CAS number of fluid (-).
h_nucleic_method (str, optional, default: null): Correlation method name (-).

Returns (float): Nucleate boiling heat transfer coefficient (W/m^2/K), or an error message if invalid.

Example 1: Gorenflo selection with CAS

Inputs:

P	Pc	q	CAS
300000	22048320	20000	7732-18-5

Excel formula:

=H_NUCLEIC(300000, 22048320, 20000, "7732-18-5")

Expected output:

3043.34

Example 2: Rohsenow method with excess temperature

Inputs:

rhol	rhog	mul	kl	Cpl	Hvap	sigma	Te	Csf	n	h_nucleic_method
957.854	0.595593	0.000279	0.68	4217	2257000	0.0589	4.9	0.011	1.26	Rohsenow

Excel formula:

=H_NUCLEIC(957.854, 0.595593, 0.000279, 0.68, 4217, 2257000, 0.0589, 4.9, 0.011, 1.26, "Rohsenow")

Expected output:

3723.66

Example 3: Cooper method with excess temperature

Inputs:

P	Pc	MW	Te	h_nucleic_method
101325	22048321	18.02	4.3	Cooper

Excel formula:

=H_NUCLEIC(101325, 22048321, 18.02, 4.3, "Cooper")

Expected output:

1558.14

Example 4: Stephan-Abdelsalam water method

Inputs:

Te	Tsat	Cpl	kl	mul	sigma	Hvap	rhol	rhog	h_nucleic_method
5	373.15	4180	0.6	0.0003	0.058	2250000	958	0.6	Stephan-Abdelsalam water

Excel formula:

=H_NUCLEIC(5, 373.15, 4180, 0.6, 0.0003, 0.058, 2250000, 958, 0.6, "Stephan-Abdelsalam water")

Expected output:

4865.78

Python Code

Show Code

from ht.boiling_nucleic import h_nucleic as ht_h_nucleic

def h_nucleic(Te=None, q=None, Tsat=None, P=None, dPsat=None, Cpl=None, kl=None, mul=None, rhol=None, sigma=None, Hvap=None, rhog=None, MW=None, Pc=None, Csf=0.013, n=1.7, kw=401, rhow=8.96, Cpw=384, angle=35, Rp=1e-06, Ra=4e-07, h_ref=None, CAS=None, h_nucleic_method=None):
    """
    Compute nucleate boiling heat transfer coefficient with method selection.

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

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

    Args:
        Te (float, optional): Excess wall temperature (K). Default is None.
        q (float, optional): Heat flux (W/m^2). Default is None.
        Tsat (float, optional): Saturation temperature at operating pressure (K). Default is None.
        P (float, optional): Saturation pressure of fluid (Pa). Default is None.
        dPsat (float, optional): Saturation pressure difference at excess temperature (Pa). Default is None.
        Cpl (float, optional): Heat capacity of liquid (J/kg/K). Default is None.
        kl (float, optional): Thermal conductivity of liquid (W/m/K). Default is None.
        mul (float, optional): Viscosity of liquid (Pa*s). Default is None.
        rhol (float, optional): Density of the liquid (kg/m^3). Default is None.
        sigma (float, optional): Surface tension of liquid (N/m). Default is None.
        Hvap (float, optional): Heat of vaporization of the fluid (J/kg). Default is None.
        rhog (float, optional): Density of the produced gas (kg/m^3). Default is None.
        MW (float, optional): Molecular weight of fluid (g/mol). Default is None.
        Pc (float, optional): Critical pressure of fluid (Pa). Default is None.
        Csf (float, optional): Rohsenow coefficient specific to fluid and metal (-). Default is 0.013.
        n (float, optional): Rohsenow constant (-). Default is 1.7.
        kw (float, optional): Thermal conductivity of wall material (W/m/K). Default is 401.
        rhow (float, optional): Density of wall material (kg/m^3). Default is 8.96.
        Cpw (float, optional): Heat capacity of wall material (J/kg/K). Default is 384.
        angle (float, optional): Contact angle of bubble with wall (degrees). Default is 35.
        Rp (float, optional): Surface roughness parameter for the Cooper method (m). Default is 1e-06.
        Ra (float, optional): Roughness parameter for the Gorenflo method (m). Default is 4e-07.
        h_ref (float, optional): Reference heat transfer coefficient for Gorenflo (W/m^2/K). Default is None.
        CAS (str, optional): CAS number of fluid (-). Default is None.
        h_nucleic_method (str, optional): Correlation method name (-). Valid options: Gorenflo 1993, Stephan Abdelsalam water, Stephan Abdelsalam cryogenic, Stephan Abdelsalam general, HEDH Taborek, Forster Zuber, Rohsenow, Cooper, Bier, Montinsky, McNelly. Default is None.

    Returns:
        float: Nucleate boiling heat transfer coefficient (W/m^2/K), or an error message if invalid.
    """
    try:
        return ht_h_nucleic(
            Te=Te,
            q=q,
            Tsat=Tsat,
            P=P,
            dPsat=dPsat,
            Cpl=Cpl,
            kl=kl,
            mul=mul,
            rhol=rhol,
            sigma=sigma,
            Hvap=Hvap,
            rhog=rhog,
            MW=MW,
            Pc=Pc,
            Csf=Csf,
            n=n,
            kw=kw,
            rhow=rhow,
            Cpw=Cpw,
            angle=angle,
            Rp=Rp,
            Ra=Ra,
            h0=h_ref,
            CAS=CAS,
            Method=h_nucleic_method,
        )
    except Exception as e:
        return f"Error: {str(e)}"

Online Calculator

Excess wall temperature (K).

Heat flux (W/m^2).

Tsat

Saturation temperature at operating pressure (K).

Saturation pressure of fluid (Pa).

dPsat

Saturation pressure difference at excess temperature (Pa).

Cpl

Heat capacity of liquid (J/kg/K).

Thermal conductivity of liquid (W/m/K).

mul

Viscosity of liquid (Pa*s).

rhol

Density of the liquid (kg/m^3).

sigma

Surface tension of liquid (N/m).

Hvap

Heat of vaporization of the fluid (J/kg).

rhog

Density of the produced gas (kg/m^3).

Molecular weight of fluid (g/mol).

Critical pressure of fluid (Pa).

Csf

Rohsenow coefficient specific to fluid and metal (-).

Rohsenow constant (-).

Thermal conductivity of wall material (W/m/K).

rhow

Density of wall material (kg/m^3).

Cpw

Heat capacity of wall material (J/kg/K).

angle

Contact angle of bubble with wall (degrees).

Surface roughness parameter for the Cooper method (m).

Roughness parameter for the Gorenflo method (m).

h_ref

Reference heat transfer coefficient for Gorenflo (W/m^2/K).

CAS

CAS number of fluid (-).

h_nucleic_method

Correlation method name (-).