Spiral defect chaos in Rayleigh-Bénard convection

Motivated by recent experiments on Rayleigh-B\'enard convection, where spiral defect chaos was discovered, we have simulated the Boussinesq equations for the appropriate Rayleigh numbers not far from threshold for large aspect ratio systems using a Galerkin method. A detailed analysis of the results reproduces the experimental findings almost quantitatively. A critical comparison with recent model calculations is also presented. Our investigations show that the new spatiotemporal pattern must be considered generic for Rayleigh-B\'enard convection.