Numerical observations of dynamic behavior in two-dimensional compressible convection

Using numerical simulations of the anelastic partial differential equations, convective flow in a two-dimensional polytropic atmosphere is investigated. Fixing the aspect ratio at unity and choosing the viscosity as the order parameter, the numerical solutions have indicated a variety of dynamic behavior including (i) oscillatory motion with a period of order the eddy turnover time, (ii) quasiperiodic motion with a long period much longer than an eddy turnover time, and (iii) at least two branches of solutions in certain regimes.