Consider a case where isotropic friction (TB,FRIC) field data is dependent on both temperature and sliding distance. Assume the following command input:
TB,FRIC,1,2, ,ISO TBFIELD,TEMP,100.0 TBFIELD,SLDI,0.1 TBDATA,1,0.3 TBFIELD,SLDI,0.5 TBDATA,1,0.5 TBFIELD,TEMP,200.0 TBFIELD,SLDI,0.2 TBDATA,1,0.2 TBFIELD,SLDI,0.7 TBDATA,1,0.1
Listing the data shows a user-defined 4x2 grid:
(FRIC) Table For Material 1
Data for Isotropic friction
TEMPERATURE = 100.00
SLIDE DIST = 0.10000
FRICTION DIR. FRICTION COEFF.
1 0.30000
TEMPERATURE = 100.00
SLIDE DIST = 0.50000
FRICTION DIR. FRICTION COEFF.
1 0.50000
TEMPERATURE = 200.00
SLIDE DIST = 0.20000
FRICTION DIR. FRICTION COEFF.
1 0.20000
TEMPERATURE = 200.00
SLIDE DIST = 0.70000
FRICTION DIR. FRICTION COEFF.
1 0.10000
A tabular format represents the data in the 4x2 grid as shown:
| Sliding Distance | ||||
| Temperature | 0.1 | 0.2 | 0.5 | 0.7 |
| 100 | 0.3 | 0.5 | ||
| 200 | 0.2 | 0.1 | ||
When defining tabular data, the first specified field variable forms the rows of the table. The subsequent variables form the columns. In this example, Temperature is the first defined field variable.
In this case, the user defined only four out of a possible eight grid locations.
To populate the interpolation search space, the program fills the missing grid points in each row from left to right. If the first or subsequent grid locations of a row are not defined, the program uses the first defined value within the row to backfill the grid. The program then fills any undefined locations within the grid by linearly interpolating between defined points in each row. If the last value(s) along a row are not defined, the program gives them the last previously defined value within that row.
Therefore, based on the defined field-dependent friction values, the program generates the following grid automatically (where values in italics represent those provided by the program):
| Sliding Distance | ||||
| Temperature | 0.1 | 0.2 | 0.5 | 0.7 |
| 100 | 0.3 | 0.35 | 0.5 | 0.5 |
| 200 | 0.2 | 0.2 | 0.14 | 0.1 |