  The vertices of curvilinear elements usually lie on the exact domain.
However, the additional grid points introduced for the higher-order polynomial
of numerical solution often are located slightly out of the domain to generate
geometric approximation error. Considered the main cause of the conservational
error, this error is relatively smaller than discretization error but large
enough to significantly deteriorate a long time integration. This paper
proposes a novel scheme with geometry-aligned moving frames and the removal of
corresponding spurious divergence to reduce the conservational error caused by
geometric approximation error.
