The primary objective of this research is to investigate the influence of thermal damping and surface drag on the equilibrium behavior of nonlinear baroclinic waves. This will be done by carrying out numerical experiments with a multi-level primitive equation model. The simulations will first be of a single-wave type (in which the nonlinear interactions are largely those between one zonal wave and the zonal-mean flow), and then be multiple-wave in nature (with considerable interactions between different zonal waves). In the numerical experiments the effects of thermal damping and surface drag will be simply represented, by Newtonian cooling and a simple frictional parameterization. Analysis of the simulations will focus upon the "regime" character and variability, and also on the structure of the equilibrated zonal-mean flows. This work will contribute to the basic understanding of fully developed baroclinic flows in which asymmetric external forcing is absent. This research is important because the dynamics of the atmospheric waves to be studied has a profound influence on extended weather features, and hence climate. Improvements in climate modeling and prediction require enhanced knowledge of these dynamics.