The azimuthal correlation function has been calculated as a function of beam energy and impact parameter for the 40Ar+27Al system from 36 MeV/nucleon to 100 MeV/nucleon via a quantum molecular dynamics (QMD) approach. The anisotropy of the azimuthal correlation at midrapidity interval becomes weaker with increasing beam energy and collision centrality. Around 100 MeV/nucleon the azimuthal correlation tends to be flat which indicates the rotational collective motion disappears. The vanishing of rotation may be due to the short lifetime of the emitter as suggested by the two-particle correlation function at small relative momenta. A method to estimate the fluctuation of the experimental reaction plane with respect to the true reaction plane is presented also via the azimuthal correlation function.