The steady gas-particle flow in risers under variant operating conditions was simulated using a k-epsilon-k(p) -epsilon(p) -Theta two-fluid model, which describes the dense turbulent gas-particle flow. The particle temperature Theta, the scale of the fluctuant energy of particles in micro scale, and the particle turbulent energy k p that describes the particle fluctuation in meso scale can be predicted by the numerical simulation. Further investigation shows that different flow parameters influence the particle fluctuation in different ways and that solid volume fraction significantly affects the particle fluctuation and particle dispersion behavior.