ESTS0576 GRIDMAKER.

1. NAME OR DESIGNATION OF PROGRAM:  GRIDMAKER.

3. DESCRIPTION OF PROGRAM OR FUNCTION

GRIDMAKER serves as a preprocessor for finite element models in solving two- and three-dimensional subsurface flow and pollutant transport problems.  It is designed to generate three-point triangular or four-point quadrilateral elements for two-dimensional domains and eight-point hexahedron elements for three-dimensional domains. A two-dimensional domain of an aquifer with a variable depth layer is treated as a special case for depth-integrated two-dimensional, finite element subsurface flow models. The program accommodates the need for aquifers with heterogeneous systems by identifying the type of material in each element.

4. METHOD OF SOLUTION

Based on the method of conformal mapping, the generation of interior nodal points within the two-dimensional domain of interest is performed numerically by the boundary integral element method (BIEM). For a three-dimensional domain, the BIEM techniques are applied in the projected horizontal plane, while the  vertical coordinate is transformed by a normalized transformation using local layer thickness.

5. RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM:

6. TYPICAL RUNNING TIME:  Most problems run in seconds to minutes.

The sample problem was executed in three different types of computers: 1) PC-Brett Pentium processor of 75 MHz running  MS-DOS 6.2; 2) DEC VAX 6000/510 running OpenVMS V6.1; 3) DEC 3000 Model 300X - Alpha AXP Architecture Workstation running DEC OSF/1 V3.2. The time required to run the sample problem on the VAX under OpenVMS V6.1 is 2.8 seconds (CPU time). On the PC Brett, Pentium processor of 75 MHz, 2.8 seconds (elapsed time) are required to run  the sample problem. Only a few tenths of seconds are required in the DEC 3000 Model 300X (Alpha AXP Workstation).

7. UNUSUAL FEATURES OF THE PROGRAM

GRIDMAKER generates grids for groundwater models and has capability for flexible geometry grids.

8. RELATED AND AUXILIARY PROGRAMS

FEWA and 3DFEMWATER are groundwater modeling codes which have been used with GRIDMAKER.

10. REFERENCES:

- T.K. Tsay et al.:
  Gridmaker: A Grid Generator for Two- and Three- Dimensional Finite
  Element Subsurface Flow Models
  ORNL-6613 (June 1990)

11. MACHINE REQUIREMENTS:  None specific to code in current dimensioning.

The peak working set size to execute the sample problem on the VAX under OpenVMS V6.1 is 412 Kbyte - On the PC Brett, Pentium processor of 75 MHz, base memory 640 Kbyte and extended memory of 16 MByte, the filesize of the executables created with the Lahey compiler system F77L/EM-32 (compiler Version 5.20 and linker Version 5.1L and "-STUB RUNB" option activated at linkage) is 1.25 Mbyte - On the Alpha/AXP architecture workstation under OSF/1 V3.2 with 96 MByte available memory, the filesize of the executable created with the DEC Fortran (f77) compiler V3.4 is 80 Kbyte.

13. OPERATING SYSTEM UNDER WHICH PROGRAM IS EXECUTED:  VAX/VMS.

The program GRIDMAKER was compiled, linked and executed in three different types of computers running three different types  of operating systems: 1) PC-Brett Pentium processor of 75 MHz running MS-DOS 6.2. The Lahey F77L/EM-32 compiler (version 5.20) and linker (Version 5.1L) were used to compile the GRIDMAKER executable. 2) DEC VAX 6000/510 running OpenVMS V6.1; the DEC Fortran-77 compiler was used to compile the GRIDMAKER executable. 3) DEC 3000 Model 300X - Alpha AXP Architecture Workstation running OSF/1 version 3.2; the DEC fortran compile f77 (V3.4) was used to compile  the GRIDMAKER executable.

14. OTHER PROGRAMMING OR OPERATING INFORMATION OR RESTRICTIONS

Mouse
option is currently available. Slight mapping errors are present. Input grid boundaries slightly off from output and boundaries. Program uses a multiple implied do list in some of its output statements. Depending on the compiler used, these three statements may have to be changed to work. The logic is straightforward, the only potential problem is with the single line statement format.

15. NAME AND ESTABLISHMENT OF AUTHORS

  T.K. Tsay
  Syracuse University, NY (United States)
  G.T. Yeh
  Pennsylvania State University, College Station (United States)
  G.V. Wilson
  University of Tennessee, Knoxville (United States)
  L.E. Toran
  Oak Ridge National Laboratory, TN (United States)

File name	File description	Records
ESTS0576_01.001	Information file of the program GRIDMAKER	201
ESTS0576_01.002	Source file of the program GRIDMAKER	1221
ESTS0576_01.003	Batch file to create the GRIDMAKE executable	35
ESTS0576_01.004	Executable of program GRIDMAKER (for PC's)	0
ESTS0576_01.005	Auxiliary file of Lahey runtime errors	0
ESTS0576_01.006	VMS command file to create the GRIDMAKE exec	20
ESTS0576_01.007	Sample input file to run the GRIDMAKE exec .	33
ESTS0576_01.008	Sample ouput file (VAX under OpenVMS)	2799
ESTS0576_01.009	Auxiliary output file (VAX under OpenVMS)	57
ESTS0576_01.010	Sample output file (PC-Pentium under MS-DOS)	2799
ESTS0576_01.011	Auxiliary output file (PC-Pentium, MS-DOS)	57
ESTS0576_01.012	Sample output file (DEC Alpha under OSF/1)	2799
ESTS0576_01.013	Auxiliary output file (DEC Alpha, OSF/1)	57
ESTS0576_01.014	DOS file-names	14