CTB_DP_ZUKAUSKAS

This function computes pressure drop for crossflow through a tube bank using the Zukauskas approach. It relates Reynolds-number-dependent resistance to tube-row count and bundle geometry.

The result provides a hydraulic estimate for external-flow tube-bank arrangements in heat exchanger analysis.

Excel Usage

=CTB_DP_ZUKAUSKAS(Re, n, ST, SL, D, rho, Vmax)

Re (float, required): Reynolds number (-).
n (int, required): Number of tube rows (-).
ST (float, required): Transverse pitch (m).
SL (float, required): Longitudinal pitch (m).
D (float, required): Tube outer diameter (m).
rho (float, required): Fluid density (kg/m^3).
Vmax (float, required): Maximum velocity (m/s).

Returns (float): Pressure drop across the tube bank, or an error message if invalid.

Example 1: Example staggered pitch case

Inputs:

Re	n	ST	SL	D	rho	Vmax
13943	7	0.0313	0.0343	0.0164	1.217	12.6

Excel formula:

=CTB_DP_ZUKAUSKAS(13943, 7, 0.0313, 0.0343, 0.0164, 1.217, 12.6)

Expected output:

235.229

Example 2: Example inline pitch case

Inputs:

Re	n	ST	SL	D	rho	Vmax
13943	7	0.0313	0.0313	0.0164	1.217	12.6

Excel formula:

=CTB_DP_ZUKAUSKAS(13943, 7, 0.0313, 0.0313, 0.0164, 1.217, 12.6)

Expected output:

161.147

Example 3: Lower Reynolds number case

Inputs:

Re	n	ST	SL	D	rho	Vmax
500	5	0.04	0.04	0.02	1.2	4

Excel formula:

=CTB_DP_ZUKAUSKAS(500, 5, 0.04, 0.04, 0.02, 1.2, 4)

Expected output:

10.8202

Example 4: Higher Reynolds number case

Inputs:

Re	n	ST	SL	D	rho	Vmax
50000	10	0.05	0.06	0.025	1.1	20

Excel formula:

=CTB_DP_ZUKAUSKAS(50000, 10, 0.05, 0.06, 0.025, 1.1, 20)

Expected output:

826.151

Python Code

Show Code

from ht.conv_tube_bank import dP_Zukauskas as ht_dP_Zukauskas

def ctb_dp_zukauskas(Re, n, ST, SL, D, rho, Vmax):
    """
    Compute tube bank pressure drop using the Zukauskas method.

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

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

    Args:
        Re (float): Reynolds number (-).
        n (int): Number of tube rows (-).
        ST (float): Transverse pitch (m).
        SL (float): Longitudinal pitch (m).
        D (float): Tube outer diameter (m).
        rho (float): Fluid density (kg/m^3).
        Vmax (float): Maximum velocity (m/s).

    Returns:
        float: Pressure drop across the tube bank, or an error message if invalid.
    """
    try:
        return ht_dP_Zukauskas(
            Re=Re,
            n=n,
            ST=ST,
            SL=SL,
            D=D,
            rho=rho,
            Vmax=Vmax,
        )
    except Exception as e:
        return f"Error: {str(e)}"

Online Calculator

Re *

Reynolds number (-).

n *

Number of tube rows (-).

ST *

Transverse pitch (m).

SL *

Longitudinal pitch (m).

D *

Tube outer diameter (m).

rho *

Fluid density (kg/m^3).

Vmax *

Maximum velocity (m/s).