Based on the concept of the constitutive relation error along with the residuals of both the origin and the dual problems,a goal-oriented error estimation method with extended degrees of freedom is developed.It leads to the high quality local error bounds in the problem of the direct-solution steady-state dynamic analysis with a frequency-domain finite element,which involves the enrichments with plural variable basis functions.The solution of the steady-state dynamic procedure calculates the harmonic response directly in terms of the physical degrees of freedom in the model,which uses the mass,damping,and stiffness matrices of the system.A three-dimensional finite element example is carried out to illustrate the computational procedures.
Based on the concept of the constitutive relation error along with the residuals of both the origin and the dual problems, a goal-oriented error estimation method with extended degrees of freedom is developed. It leads to the high quality locM error bounds in the problem of the direct-solution steady-state dynamic analysis with a frequency-domain finite element, which involves the enrichments with plural variable basis functions. The solution of the steady-state dynamic procedure calculates the harmonic response directly in terms of the physical degrees of freedom in the model, which uses the mass, damping, and stiffness matrices of the system. A three-dimensional finite element example is carried out to illustrate the computational procedures.