# computing viscosity

hello dear
i’m trying to simulate water-cu and compute viscosity in output.i have read the manual and examples that are in lammps examples (https://github.com/lammps/lammps/tree/master/examples).example.example) for viscosity is in units lj and dimension2 but my problem set up is units real and diension 3…refer to manual for units real dynamic viscosity unit is poise but for units lj dy visc is reduced LJ viscosity, where eta* = eta sigma^3 / epsilon / tau…i dont know which part of code should be changed.
can anybody help me?
i appreciate any help
thanks
regard

viscosity example

hello dear
I’m trying to simulate water-cu and compute viscosity in output.i have read the manual and examples that are in lammps examples (https://github.com/lammps/lammps/tree/master/examples).example.example) for viscosity is in units lj and dimension2 but my problem set up is units real and diension 3…refer to manual for units real dynamic viscosity unit is poise but for units lj dy visc is reduced LJ viscosity, where eta* = eta sigma^3 / epsilon / tau…i dont know which part of code should be changed.
can anybody help me?
i appreciate any help
thanks
regard

viscosity example

hello dear
i’m trying to simulate water-cu and compute viscosity in output.i have read the manual and examples that are in lammps examples (https://github.com/lammps/lammps/tree/master/examples).example.example) for viscosity is in units lj and dimension2 but my problem set up is units real and diension 3…refer to manual for units real dynamic viscosity unit is poise but for units lj dyn visc is reduced LJ viscosity, where eta* = eta sigma^3 / epsilon / tau…i dont know which part of code should be changed.
can anybody help me?
i appreciate any help
thanks
regard

viscosity example

Because you “appreciate any help” here is a piece of advice to you:
1-) Avoid spamming any service of this kind
2-) Personalize by displaying some creativity with the opening and ending of your messages (you have already sent a billion messages to this list with the “hello dear/thanks regard” duo)
3-) Show that you are a human being capable of some incremental learning and not some kind of AI trying to put together a workable lammps input deck
4-) Avoid at all cost coming across as a fraudster with sentences like “i dont know which part of code should be changed” when referring to trying to modify other’s script
5-) Acknowledge when people offer you advice at no cost as have been done here by members of the lammps team
6-) Consider a different pathway or at least get out of that MD course you’re taking

The above does not solve your water-Cu problem but I think will do you much good if the advice is considered seriously beyond my bit of sarcasm.
Carlos

dear users
i’m simulating water-cu and compute viscosity in output.i have read the manual and examples that are in lammps examples (https://github.com/lammps/lammps/tree/master/examples)..example)when i ran the code i got a big number for viscosity=3*10^24
can anybody help me?
thanks

dear users
i'm simulating water-cu and compute viscosity in output.i have read the
manual and examples that are in lammps examples (
https://github.com/lammps/lammps/tree/master/examples).
<https://github.com/lammps/lammps/tree/master/examples).example>when i
ran the code i got a big number for viscosity=3*10^24
can anybody help me?

​mehdi,

you must be thinking that people here are complete idiots and suckers that
can be fooled by the most trivial of things. do you seriously expect that
nobody can tell that you just ran the script that you already *know* needs
to be adapted? and you just quote the expected-to-be-wrong number. this is
really insulting the intelligence of the people that have already given you
good an well-meaning advice (which you preferred to ignore for the most
part).

thus ​you are far beyond *deserving* any kind of help. you don't pay
attention to anything what people tell you beyond the most trivial things.
applying something green-kubo and figuring out how you need to run it for a
3d system with a different unit set of what the example has as well as what
kind of parameters you need (number of steps and correlation length) is an
advanced MD topic. yet your input clearly shows that you cannot even do a
rather basic task like setting up a correct simple bulk water​ simulation
(what water model is it exactly that you are simulating? can you reproduce
any of its documented properties?), let alone a mixed hybrid system. you
obviously have not studied MD basics sufficiently, nor read up on the
statistical mechanical background of green-kubo or what the practical
implications are for using it. how on earth can you expect that you get
things right?

as carlos already pointed out, that simply doing (more-or-less) random
things and then coming back to the list and asking us to fix your input is
not going to work. nobody here has the desire to do *your* thinking and
*your* project for you and since you have failed to show any interest in
actually *learning* anything for yourself, you are not likely to get any
help at this point. people here can be very helpful, but they expect people
that receive the help to pay respect their effort by demonstrating that
their help motivates people to make an effort to become more knowledgeable
and understanding what they are doing. as soon as they sense they are being
exploited, like your case is showing in the most extreme fashion that i can
recall since subscribing to the list a very long time ago, they will ignore
you or worse.

or in short: get stuffed!

axel.