NU_KITOH

This function calculates the Nusselt number for supercritical turbulent tube flow using the Kitoh correlation. It is based on Reynolds and Prandtl numbers and can optionally modify the Prandtl exponent as a function of enthalpy, mass flux, and wall heat flux.

Nu = C\,Re^{m}Pr^{n(H,G,q)}

Excel Usage

=NU_KITOH(Re, Pr, H, G, q)
  • Re (float, required): Reynolds number with bulk fluid properties (-).
  • Pr (float, required): Prandtl number with bulk fluid properties (-).
  • H (float, optional, default: null): Enthalpy of water when applicable (J/kg).
  • G (float, optional, default: null): Mass flux of the fluid (kg/m^2/s).
  • q (float, optional, default: null): Heat flux to the wall (W/m^2).

Returns (float): Nusselt number with bulk fluid properties (-).

Example 1: Kitoh correlation example

Inputs:

Re Pr H G q
100000 1.2 1300000 1500 5000000

Excel formula:

=NU_KITOH(100000, 1.2, 1300000, 1500, 5000000)

Expected output:

331.802

Example 2: Kitoh correlation bulk properties only

Inputs:

Re Pr
80000 1.1

Excel formula:

=NU_KITOH(80000, 1.1)

Expected output:

235.656

Example 3: Kitoh correlation mid Reynolds number

Inputs:

Re Pr H G q
200000 0.9 1800000 1200 3000000

Excel formula:

=NU_KITOH(200000, 0.9, 1800000, 1200, 3000000)

Expected output:

570.322

Example 4: Kitoh correlation higher Reynolds number

Inputs:

Re Pr H G q
450000 1.4 2200000 1700 6000000

Excel formula:

=NU_KITOH(450000, 1.4, 2200000, 1700, 6000000)

Expected output:

416.26

Python Code

Show Code
from ht.conv_supercritical import Nu_Kitoh as ht_Nu_Kitoh

def Nu_Kitoh(Re, Pr, H=None, G=None, q=None):
    """
    Calculate Nusselt number for supercritical flow using the Kitoh correlation.

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

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

    Args:
        Re (float): Reynolds number with bulk fluid properties (-).
        Pr (float): Prandtl number with bulk fluid properties (-).
        H (float, optional): Enthalpy of water when applicable (J/kg). Default is None.
        G (float, optional): Mass flux of the fluid (kg/m^2/s). Default is None.
        q (float, optional): Heat flux to the wall (W/m^2). Default is None.

    Returns:
        float: Nusselt number with bulk fluid properties (-).
    """
    try:
        return ht_Nu_Kitoh(Re=Re, Pr=Pr, H=H, G=G, q=q)
    except Exception as e:
        return f"Error: {str(e)}"

Online Calculator

Reynolds number with bulk fluid properties (-).
Prandtl number with bulk fluid properties (-).
Enthalpy of water when applicable (J/kg).
Mass flux of the fluid (kg/m^2/s).
Heat flux to the wall (W/m^2).