  Based on a viscous hydrodynamic model with anisotropically perturbed Gubser
flow and isothermal Cooper-Frye freezeout at early times, we analytically
compute the flow harmonics $v_n(p_T)$ and study how they scale with the
harmonic number $n$ and transverse momentum, as well as the system size, shear
and bulk viscosity coefficients, and collision energy. In particular, we find
that the magnitude of shear viscous corrections grows linearly with $n$. The
mixing between different harmonics is also discussed. While this model is
rather simple as compared to realistic heavy-ion collisions, we argue that the
scaling results presented here may be meaningfully compared to experimental
data collected over many energies, system sizes, and geometries.
