A series of direct numerical simulations in large computational domains hasbeen performed in order to probe the spatial feature robustness of the Taylorrolls in turbulent Taylor-Couette (TC) flow. The latter is the flow between twocoaxial independently rotating cylinders of radius $r_i$ and $r_o$,respectively. Large axial aspect ratios $\Gamma = 7$-$8$ (with $\Gamma =L/(r_o-r_i)$, and $L$ the axial length of the domain) and a simulation with$\Gamma=14$ were used in order to allow the system to select the most unstablewavenumber and to possibly develop multiple states. The radius ratio was takenas $\eta=r_i/r_o=0.909$, the inner cylinder Reynolds number was fixed to$Re_i=3.4\cdot10^4$, and the outer cylinder was kept stationary, resulting in africtional Reynolds number of $Re_\tau\approx500$, except for the $\Gamma=14$simulation where $Re_i=1.5\cdot10^4$ and $Re_\tau\approx240$. The large-scalerolls were found to remain axially pinned for all simulations. Depending on theinitial conditions, stable solutions with different number of rolls $n_r$ androll wavelength $\lambda_z$ were found for $\Gamma=7$. The effect of$\lambda_z$ and $n_r$ on the statistics was quantified. The torque and meanflow statistics were found to be independent of both $\lambda_z$ and $n_r$,while the velocity fluctuations and energy spectra showed some box-sizedependence. Finally, the axial velocity spectra was found to have a very sharpdrop off for wavelengths larger than $\lambda_z$, while for the smallwavelengths they collapse.
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