In the present paper, Molecular Dynamics Simulation (MDS) is performed for Poiseuille flow of liquid Argon in a nanochannel by embedding the fluid particles in an external force with different potential functions. Three types of Lennard-Jones (LJ) potentials are used as interatomistic or molecular models for evaluations of interactions and density, velocity profiles across the channel are investigated. The interatomic potentials are LJ 12-6 potential, LJ 9-6 potential and LJ-Smooth potential. Density and velocity profiles across the channel are investigated. Obtained results show that hydrodynamic characteristics and behavior of flow depends on the type of interaction potential. It is shown that the LJ 9-6 predictions for velocity and temperature are larger than those of LJ12-6 and LJ-Smooth potentials. Also, applying LJ 9-6 results in further calculations time. The results show the effect of interaction force model on the understanding and analyzing of nanoscale flows.