  Cataclysmic Variables (CVs) and Symbiotic Binaries are close (or not so
close) binary star systems which contain both a white dwarf (WD) primary and a
larger cooler secondary star that typically fills its Roche Lobe. The cooler
star is losing mass through the inner Lagrangian point of the binary and a
fraction of this material is accreted by the WD. Here we report on our
hydrodynamic studies of the thermonuclear runaway (TNR) in the accreted
material that ends in a Classical Nova explosion. We have followed the
evolution of the TNRs on both carbon-oxygen (CO) and oxygen-neon (ONe) WDs. We
report on 3 studies in this paper. First, simulations in which we accrete only
solar matter using NOVA (our 1-D, fully implicit, hydro code). Second, we use
MESA for similar studies in which we accrete only Solar matter and compare the
results. Third, we accrete solar matter until the TNR is ongoing and then
switch the composition in the accreted layers to a mixed composition: either
25% WD and 75% solar or 50% WD and 50% Solar matter. We find that the amount of
accreted material is inversely proportional to the initial 12C abundance (as
expected). Thus, accreting solar matter results in a larger amount of accreted
material to fuel the outburst; much larger than in earlier studies where a
mixed composition was assumed from the beginning of the simulation. Our most
important result is that all these simulations eject significantly less mass
than accreted and, therefore, the WD is growing in mass toward the
Chandrasekhar Limit.
