Keyword type: step
This option is used to define the correlation length to be used to calculate the random fields in a *ROBUST DESIGN analysis. It has the unit of length and is a measure for how connected the outer geometry is. A small correlation length means that the surface finish of the structure allows for high frequency geometric deviations such as very local dents. A large correlation length allows only for low frequency deviations, i.e. any deviations are rather smooth and extend over a larger area. A small correlation length will require a larger set of random field vectors to represent the geometric tolerances to a given accuracy.
Example: *CORRELATION LENGTH 20.
specifies a correlation length of 20 length units.
Example files: beamprand.