Context : The Kepler mission ’ s discovery of a number of circumbinary planets orbiting close ( a _ { p } < 1.1 au ) to the stellar binary raises questions as to how these planets could have formed given the intense gravitational perturbations the dual stars impart on the disk .
The gas component of circumbinary protoplanetary disks is perturbed in a similar manner to the solid , planetesimal dominated counterpart , although the mechanism by which disk eccentricity originates differs .

Aims : This is the first work of a series that aims to investigate the conditions for planet formation in circumbinary protoplanetary disks .

Methods : We present a number of hydrodynamical simulations that explore the response of gas disks around two observed binary systems : Kepler-16 and Kepler-34 .
We probe the importance of disk viscosity , aspect-ratio , inner boundary condition , initial surface density gradient , and self-gravity on the dynamical evolution of the disk , as well as its quasi-steady-state profile .

Results : We find there is a strong influence of binary type on the mean disk eccentricity , \bar { e } _ { d } , leading to \bar { e } _ { d } = 0.02 - 0.08 for Kepler-16 and \bar { e } _ { d } = 0.10 - 0.15 in Kepler-34 .
The value of \alpha -viscosity has little influence on the disk , but we find a strong increase in mean disk eccentricity with increasing aspect-ratio due to wave propagation effects .
The choice of inner boundary condition only has a small effect on the surface density and eccentricity of the disk .
Our primary finding is that including disk self-gravity has little impact on the evolution or final state of the disk for disks with masses less than 12.5 times that of the minimum-mass solar nebula .
This finding contrasts with the results of self-gravity relevance in circumprimary disks , where its inclusion is found to be an important factor in describing the disk evolution .

Conclusions :