Characteristic-Galerkin and Galerkin/least-squares space-time formulations for the advection- diffusion equation with time-dependent domains
نویسنده
چکیده
For the advection-diffusion equation, the characteristic-Oalerkin formulations are obtained by temporal discretization of the total derivative. These formulations, by construction, are EulerianLagrangian, and therefore can handle time-dependent domains without difficulty. The Oalerkin/leastsquares space-time formulation, on the other hand, is written over the space-time domain of a problem, and therefore can handle time-dependent domains with no implementational difficulty. The purpose of this paper is to compare these two formulations based on error estimates and numerical performance, in the context of the advection-diffusion equation.
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