University of FloridaDepartment of Agricultural & Biological Engineering



Download PDunne program, sample inputs and documentation:


Program to calculate the field Ks method based on the Philip-Dunne permeameter. The permeameter is based on T. Dunne apparatus and data from the Amazon River basin, as presented by Philip (1993). The apparatus consists on a vertically inserted pipe of internal radius ri filled with water to a depth Do at time t=0. Philip (1993) replaced the disk-shaped water supply surface of radius ri by a spherical supply surface of equal area with radius ro=0.5 ri and applied an approximate dimensional analysis based on the Green-Ampt model to propose flow equations. A simplified procedure for calculating field Ks based on Philip's (1993) dimensionless analysis of this case is presented by de Haro (1998) and followed here. More details on the field application of this permeameter and solution procedure can be found in Muñoz-Carpena et al. (2002).

The program runs in DOS and UNIX mode and is written in Fortran. Command line UNIX and DOS versions as well as a complete MS-Windows interface and a simple MacOSX one are available for download.

Program Usage & Output

For Windows installations, locate setup in the distribution media and start it by clicking twice with the mouse on the windows icon. Follow the instructions on the MS-Windows installer to complete installation.

For DOS installations, unpack the contents of the ZIP package on a directory. The program (pdunne.exe) and sample files will be written into this directory. A UNIX package with a compilation script is available from the authors upon request.

The DOS and UNIX program inputs are chosen as arguments from the command line. A short description of the program use can be obtained by executing the program with no arguments:

  • > pddune <return>

    Name:     pdunne
                     (PDUNNE Philip-Dunne permeameter data)
    Version:  0.3 DOS and UNIX, 08/28/2002
                     (c) 2000 - R. Munoz-Carpena
    Use:        pdunne input_file
                     input_file: name of input file (1-12 chars.)

For example, if your executable is named pdunne.exe (pdunne in UNIX), and the input file test.pd (see example below) then you would type:

  • > pdunne test.pd <return>

This will produce a program output file in the working directory named pd.out (see example below). The file can be imported and edited in any standard ASCII text editor or word processor. When working with the MS-Windows GUI the press the button "Evaluate" after filling in the required inputs. After the calculations are done a new window appears with the results, options to rename the output file to a different name other that pd.out, and copy the data in clipboard for use in other applications.

Input/Output Example

The program input file must be written in ASCII or text format (be sure to select this option when saving the file with the editor of your choice). In the MS-Windows version of the program the GUI creates the input file after the user inputs the required data in the form provided. This is a sample input file for test.pd with results from experients in the field (last 2 rows in file):

  • 'Inputs from Philip(1993)'  -->  Description of data (40 char.)
    0.030, 0.30                           -->  ri, ho (m), pipe dimensions
    0.200 3600.0 10000.0        -->  inc.theta_i, tmed_i, tmax_i(s) (i=1,n)
    0.200 3420.0 10500.0


ri (m)= internal radius of the pipe
ho (m) = water depth in pipe at t=0
inc_thetai = Δθ, volumetric soil moisture increment in wetted area from the start to end of the experiment, i.e. Δθ=θsi, where θs and θi are the soil end (saturated) and initial volumetric water content [-] from the experiment.
tmedi (s) = time for the water to reach a depth of ho/2
tmaxi (s) = and time when the depth of water is zero in the pipe

Note that multiple points in the field can be analyzed simulataneously by adding more rows at the end of the file (like in the example above for 2 locations). The user could edit the enclosed sample file, replace the contents with the values from the case to analyze, and change the name to new name reflecting the new application.

When executing this file (see Program Use above) the following output (pd.out file) will be produced,

where Ks (m/s) is the saturated hydraulic conductivity and Psi_m (m) is Green-Ampt's suction at the wetting front obtained from the solution in each of the observation points in the field.

Program License

This program is distributed as Freeware/Public Domain under the terms of GNU-License. If the program is found useful the authors ask that acknowledgment is given to its use in any resulting publication and the authors notified. The source code is available from the authors upon request:

  • Rafael Muñoz-Carpena
    Professor, Hydrology & Water Quality
    Department of Agricultural
     & Biological Engineering
    University of Florida
    P.O. Box 110570
    287 Frazier Rogers Hall
    Gainesville, FL  32611-0570

    (352) 392-1864 x287
    622-1864 x287 (Suncom)
    (352) 392-4092 (fax)

Return to top


Return to top

This page was last updated on February 21, 2023.