Elongational flows using fix nvt/sllod

Hi All,

I have recently been performing simulations where I shear a system using fix deform wiggle and fix nvt/sllod, ie:


fix fxnvt all nvt/sllod temp {temp} {temp} 100.0

fix fxdfm all deform 1 xy wiggle {ampl} {tperiod} units box remap v


The documentation and associated literature clearly show that this gives a correct velocity profile.

Can the same simulation be performed for uniaxial elongation, ie change “xy” to “x” in the fix deform line, and still give a correct flow?

Tim O’Sullivan.

Maybe. But you should probably follow this advice:

“Note that simulation of a continuously extended system (extensional flow) can be modeled using the USER-UEF package and its fix commands.”