new in LIGGGHTS to model the needle shape particles movement

1: yes see: http://www.igg.me/at/liggghts-launcher for an example, at the moment you need to compile it yourself from sourcecode, but I'll prepare a binay when my funding goal is reached
2: yes, see http://www.cfdem.com/node/11493 some features are locked for industrial sponsors, e.g. Multisphere, Loadbalancing and a 6DOF solver for meshes
3: yes, but there are a lot of examples in the installation package
4: this is complicated, I never tried to run OF (the underlaying cfd solver) on windows, I think you need a linux machine with OF installed and than setup CFDEM coupling,
afaik the public version of CFDEM(R) does not include a solver for multispheres, so even when you use public liggghts with fix rigid you will not get good results from the cfd side because of wrong voidfraction I think.
But maybe you don't need a cfd coupled simulation when you can asume your fluid as force field like gravity and applay this forces, some viscous damping and all the other stuff to a pure DEM simulation. We did something similar in a commercial project I can't talk about ....

I would suggest first to download the source package of liggghts, compile it and play with the examples. When you get stuck ask here in the forum.

Best,
Christian.

Hello I am fairly new in Open source softwares all i am familiar with is download installer and install something. So can any one give me a bit idiot friendly step by step installation guide from experience? I am using windows 7.