Square Patterns in Rayleigh-Bénard Convection with Rotation about a Vertical Axis
نویسندگان
چکیده
We present experimental results for Rayleigh-Bénard convection with rotation about a vertical axis at dimensionless rotation rates 0 # V # 250 and e ; DTyDTc 2 1 & 0.2. Critical Rayleigh numbers and wave numbers agree with predictions of linear-stability analysis. For V * 70 and small e the patterns are cellular with local fourfold coordination and differ from the theoretically expected KüppersLortz unstable state. Stable as well as intermittent defect-free square lattices exist over certain parameter ranges. Over other ranges defects dynamically disrupt the lattice but cellular flow and local fourfold coordination is maintained. [S0031-9007(98)06696-4]
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