In this tutorial i'll explain how to get a smoke effect without using fluids just nParticles from Maya with some images mapped to sprites with some easy steps. If you have any doubts, feel free to ask me.
This is the expression used for the particles :
nParticleShape1.spriteTwistPP = rand (-180,180);
nParticleShape1.spriteNumPP = rand (1,5);
nParticleShape1.MyRot = rand (-1,1);
This is the expression used for the turbulence Field in Phase X,Y,Z:
turbulenceField1.phaseX = turbulenceField1.phaseY = turbulenceField1.phaseZ = time*.1;
Here the link with the same tutorial but better explained (in spanish)