2 THE Z88 MODULES

2.1 THE DIRECT CHOLESKY SOLVER Z88F

NOTE:

Always compare FEA calculations with analytical rough calculations, results of experiments, plausibility considerations and other tests without exeption !

The principal task of every FEA program is the calculation of the displacements. That's the job of Z88F. The calculated deflections are the starting point for a stress calculation with Z88D or nodal force calculation with Z88E.

Z88F is the right solver for small structures. For large structures launch the sparse matrix solver Z88I1 and Z88I2.

Note: The files Z88I1.TXT , Z88I2.TXT and Z88I5.TXT mentioned here are described more precisely in chapter 3.

(1) Compute Mode

Windows: Z88F > Mode > Compute Mode, Compute > Go
UNIX: z88f -c (console) or Z88F -C (Z88COM)

Input files:
Z88I1.TXT (general structure data)
Z88I2.TXT (boundary conditions, constraints)
Z88I5.TXT (surface and pressure loads), if needed

Output files:
Z88O0.TXT (processed structure data for documentation)
Z88O1.TXT (processed boundary conditions for documentation)
Z88O2.TXT (deflections)

In addition two binary files Z88O1.BNY and Z88O3.BNY are generated. These binary files are later used by Z88D (stress processor) and Z88E (nodal force processor).

(2) Test Mode

Windows: Z88F > Mode > Test Mode, Compute > Go
UNIX: z88f -t (console) or Z88F -T (Z88COM)

Input files:
Z88I1.TXT (general structure data)

Output files:
Z88O0.TXT (processed structure data for documentation)

Only the file Z88O0.TXT (processed structure data for documentation) is produced along with the memory needs for total stiffness matrix and coincidence vector plotted on the screen. Use this mode for
> Checking the memory needs for MAXGS and MAXKOI.
> Checking if Z88F interprets Z88I1.TXT correctly and, as requested, puts the data in Z88O0.TXT.