Effects of variable density on response of spherical diffusion flames under rotation

The spherical diffusion flame generated by either a porous burner or a fuel droplet in response to rotational motion was investigated through perturbation analysis, with emphasis on the effects variable density. While it was shown that main feature of the problem was adequately described by the constant-density model, the variable-density formulation revealed two new insights: (1) perturbations due to rotation decrease substantially as compared with the constant-density formulation, suggesting that the perturbing effects of rotation are substantially absorbed and thereby mitigated by the density variation, and (2) magnitude of the perturbations strongly depends on the ratio of the burner/droplet surface temperature to the ambient temperature.