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tokens: amount of condensation. It appears that the introduction of thermal conduction has been helpful to restrain the numerical diffusion. As we said in Section 4.1 , thermal conduction is a diffusive process: like numerical diffusion, it destroys the smaller structures smoothing the temperature gradients and creating a homogeneous mixture at intermediate temperature. However, unlike numerical diffusion, the scale at which thermal conduction operates does not depend on the grid resolution, but on physical conditions of the problem, in particular on the temperature of the hot coronal gas (see equation 1 ). Thus, although at very low resolutions numerical diffusion is the dominant diffusive process, increasing the resolution, thermal conduction can become the dominant process. The development of turbulence in the wake of our fountain clouds produces a hierarchy of smaller and smaller structures, following a power-law distribution. The size of the smallest structures is determined by resolution, however their survival is largely determined by thermal conduction which operates efficiently on scales below the Field length (∼ 20 pc). Therefore, the smallest clouds (a few parsec) do not influence the growth of cold gas mass because they are not able to survive, mix with hotter gas and trigger condensation. The convergence in condensation shown in Fig. 4 may reflect this change of regime. After these considerations we can conclude that the resolution 2pcx2pc is good enough for our kind of simulations and we proceed with this resolution for the rest of the paper. 4.4 Thermal conduction effects at different <inline-formula><tex-math id="TM0019" notation="LaTeX"></tex-math></inline-formula> Thermal conduction strongly depends on the temperature of the hot gas. The heat conduction flux, , is proportional to T 5/2 (see equation 2 ), then small differences of temperature lead to large differences of exchanged heat. The consequence is that at high temperatures cold structures can evaporate much faster. However, as we saw in Section 2 , when the temperature changes on scales smaller than the mean free path of the conducting electrons, thermal conduction enters in a regime of saturation and the correlation between high temperatures and high heat transfer can be mitigated. A criterion to ascertain the effects of saturated thermal conduction on a structure with length scale l is given by the global saturation parameter: For σ 0 ≳ 1, the effect of saturated thermal conduction becomes significant (Cowie McKee 1977 ; Dalton Balbus 1993 ). In our simulations, the effect of saturation is negligible for the global evolution of the cloud: σ 0 ≪ 1 for l = R cl = 100 pc, regardless of coronal temperature. However, the saturation effect on the cold cloudlets in the turbulent wake could become more and more important (σ 0 ∝ l −1 ) for increasing coronal temperature. Only at T cor = 8 × 10 6 K σ 0 ≲ 1 and at these high temperatures the saturation effect could have a slight