Numerical model reduction of 2D steady incompressible laminar flows: Application on the flow over a backward-facing step

A computationally efficient reduced order model to generate multi-parameter fluid-thermal databases

“…a) It is the amplitudes of the higher order modes that show the largest relative discrepancies. And the values of the higher Table 2 Relative errors in % resulting from minimizing the residual with both the GA and the GL þ C methods, retaining the numbers of modes displayed in (14). Errors smaller than 0.1% are rounded off to zero hereafter.…”

“…The latter can be classified into two categories: those that reduce the problem to a set of ordinary differential equations (Galerkin projection on a set of previously calculated POD modes [5]) and those that treat the problem as a minimization problem (searching for the set of modal amplitudes that minimize a pre-defined residual error in the NaviereStokes equations). Examples of the former can be found in, e.g., the articles by Galletti et al [6], Sirisup and Karniadakis [7], Burkhard et al [8], Barone et al [9], Kalashnikova et al [10] and Rapun and Vega [11], and examples of the latter in the articles by LeGresley and Alonso [12], Alonso et al [13], and Rouizi et al [14], and Bache et al [15]. In both cases, the CPU time needed to compute the ROM is much smaller than the CPU time required to run the CFD solver.…”

Heat Transfer to Separation Flow in Heat Exchangers

“…They showed that, with the increase of aspect ratio of duct the distance between top and bottom of symmetry plane effect the flow. Rouizi et al [98] investigated numerically, the two-dimensional incompressible laminar flows over backward facing step. They employed model reduction and identification technique with finite element method and observed that with the increase model order the accuracy increases.…”

An experimental study of heat transfer to turbulent separation fluid flow in an annular passage

“…Meanwhile, the separated flow without reattachment is characterized by the interaction between vortices shed from the separation points [2]. In general, this phenomenon is encountered in some engineering applications, such as flow over airfoils at large angles of attack, in channels where area suddenly increases, in wide angle diffusers [3][4][5][6][7][8], heat exchangers, combustors, nuclear reactor cooling channels [9], in power plants [10], gas turbines and electronic circuit panels [11][12].…”