  Anisotropic flows ($v_2$ and $v_4$) of light nuclear clusters are studied by
Isospin-Dependent Quantum Molecular Dynamics model for the system of $^{86}$Kr
+ $^{124}$Sn at intermediate energy and large impact parameters.
Number-of-nucleon scaling of the elliptic flow ($v_2$) are demonstrated for the
light fragments up to $A$ = 4, and the ratio of $v_4/v_2^2$ shows a constant
value of 1/2. In addition, the momentum-space densities of different clusters
are also surveyed as functions of transverse momentum, in-plane transverse
momentum and azimuth angle relative to the reaction plane. The results can be
essentially described by momentum-space power law. All the above phenomena
indicate that there exists a number-of-nucleon scaling for both anisotropic
flow and momentum-space densities for light clusters, which can be understood
by the coalescence mechanism in nucleonic degree of freedom for the cluster
formation.
