Disturbance region update method for steady compressible flows

A new methodology capable of achieving considerable acceleration in iteration together with lower memory requirements, named as the disturbance region update method (DRUM), is presented for steady compressible flow simulation. The methodology is constructed based on the characteristics of the time-marching solution process, utilizing a time-dependent dynamic computational domain. The update of the solution needs only be executed within the dynamic domain containing solely the disturbed cells with non-convergent solutions, while the update of the dynamic domain can be realized by measuring the propagation of disturbances. Eight test cases, including a subsonic, three mixed subsonic-supersonic, and four supersonic flow problems, are chosen to validate the developed methodology. Numerical results of these test cases demonstrate that, firstly, DRUM is equally robust for different reconstruction, spatial discretization and time-marching schemes, initializations as well as for discontinuous walls; secondly, it accomplishes remarkable convergence speed for solving all compressible flow problems, benefiting from the reduction in the computational effort per iteration and the reduction in the total number of iterations; thirdly, it may also save notably in terms of the maximum memory requirements for supersonic problems.