  Turbulent flow across an in-line array of tube-banks with transverse and
longitudinal pitch PT /D = 2.67, and PL /D = 2.31, has been simulated
successfully by Large Eddy Simulation (LES) based on the dynamic Smagorinsky
subgrid scale model (SGS), in which a wall-layer model is used to reduce the
computational cost. The flow structures across the tube-banks were examined
through the normalized Q criterion. The surface pressure characteristics from
the middle cylinder within each column of cylinders are found to agree well
with the existing experimental data, as did also the values of drag and lift
coefficients. These results indicate that cylinders from the second column
experience the minimum drag force and maximum lift force fluctuation. Spectral
analyses were performed for velocity signals sampled behind each middle
cylinder axis, which show that the dominant vortex shedding frequency does not
vary across the tube-banks. On this basis, we also examined the shear layer
instability. Finally, we report auto-correlation functions for streamwise and
cross velocity fluctuations as a function of the spanwise length.
