  A non negligible fraction of white dwarf stars show the presence of heavy
elements in their atmospheres. The most accepted explanation for this
contamination is the accretion of material coming from tidally disrupted
planetesimals, which form a debris disk around the star. We provide a grid of
models for hydrogen rich white dwarfs accreting heavy material. We sweep a 3D
parameter space involving different effective temperatures, envelope's hydrogen
content and accretion rates. The grid is appropriate for determining accretion
rates in white dwarfs showing the presence of heavy elements. Full evolutionary
calculations of accreting white dwarfs were computed including all relevant
physical processes, particularly the fingering (thermohaline) convection, a
process neglected in most previous works, that has to be considered to obtain
realistic estimations. Accretion is treated as a continuous process and bulk
Earth composition is assumed for the accreted material. We obtain final
(stationary or near stationary) and reliable abundances for a grid of models
representing hydrogen rich white dwarfs of different effective temperatures and
hydrogen contents, applied to various accretion rates. Our results provide
estimates of accretion rates, accounting for thermohaline mixing, to be used
for further studies on evolved planetary systems.
