Angular velocity influence on the gas dynamics and magnetic field structure: Ω_bar = 15.0 Gyr^-1 in 1st row, Ω_bar = 20.0 Gyr^-1 in 2nd row, Ω_bar = 25.0 Gyr^-1 in 3rd row, Ω_bar = 30.0 Gyr^-1 in 4th row, Ω_bar = 50.0 Gyr^-1 in 5th row. Left column: velocity field in the frame rotating with the bar (vectors) and the gas density distribution in the galactic mid-plane (grey-scale, darker means greater density). Middle column: column density (darker means higher column density) for the inner 6 kpc × 6 kpc part of galaxy. Right column: polarized intensity (contours), polarization angles (dashes) and column density (grey-scale) smoothed to the resolution 40''.