Journal of Physics: Conference Series, Feb 1, 2021
Aimed at decreasing the numerical dissipation of weighted non-oscillatory and non-free-parameter ... more Aimed at decreasing the numerical dissipation of weighted non-oscillatory and non-free-parameter dissipation (WNND) scheme, we present an improved counterpart for shock-capturing. The new algorithm is based on the framework of Z-type weighting procedure with new local and global smoothness indicators. The performances of the proposed scheme are evaluated on several numerical tests governed by one-dimensional Euler equations. Numerical results indicate that the improved WNND scheme has advantages over the original WNND and third-order WENO-JS and WENO-Z schemes.
Since the first introduction of the weighted essentially non-oscillatory (WENO) scheme in [1], th... more Since the first introduction of the weighted essentially non-oscillatory (WENO) scheme in [1], the efficient implementation in [2] made the algorithm applicable to realistic problems. Despite the success, some analytic outcomes of the scheme were still called in question. It were Henrick et al. [3] who first pointed out that WENO5 failed to pertain the fifth-order accuracy at the critical point where f′ j = 0. They further proposed the necessary and sufficient conditions for a scheme to obtain the order. In order to provide remedies for WENO5, Henrick et al. [3] proposed a carefully designed mapping function, through which the difference between the nonlinear weight and its linear counterpart will usually have the order of Δx3. The corresponding scheme was called as WENO-M, and the improvement on resolution was shown through the comparison with WENO5.
Atomically dispersing metal atoms on supports provides an ideal strategy for maximizing metal uti... more Atomically dispersing metal atoms on supports provides an ideal strategy for maximizing metal utilization for catalysis, which is particularly important for fabricating cost‐effective catalysts based on Earth‐scarce metals. However, due to the high surface energy and thus instability of single atoms, it remains challenging to fabricate stable atomically dispersed metal catalysts. Here, strategies for stabilizing atomically dispersed metal catalysts on various supports are summarized. Based on strategies to enhance the interaction between the metal and the support to prevent the sintering of metal atoms, several approaches to stabilize supported atomically dispersed metal catalysts are then extensively discussed. To close, the importance of the interface species surrounding single atoms in determining the catalytic properties of atomically dispersed metal catalysts is discussed, together with a summary of the prospects for the development of the field.
International Journal for Numerical Methods in Fluids, Jul 4, 2020
SummaryIn this article, we present two improved third‐order weighted essentially nonoscillatory (... more SummaryIn this article, we present two improved third‐order weighted essentially nonoscillatory (WENO) schemes for recovering their design‐order near first‐order critical points. The schemes are constructed in the framework of third‐order WENO‐Z scheme. Two new global smoothness indicators, τL3 and τL4, are devised by a nonlinear combination of local smoothness indicators (ISk) and reference values (ISG) based on Lagrangian interpolation polynomial. The performances of the proposed schemes are evaluated on several numerical tests governed by one‐dimensional linear advection equation or one‐ and two‐dimensional Euler equations. Numerical results indicate that the presented schemes provide less dissipation and higher resolution than the original WENO3‐JS and subsequent WENO3‐N scheme.
Abstract In this paper, the performance of the optimized symmetric fourth-order weighted essentia... more Abstract In this paper, the performance of the optimized symmetric fourth-order weighted essentially non-oscillatory scheme (WENO-OS4) in direct numerical simulation of compressible turbulence is demonstrated and compared with other three optimized WENO schemes. The compressible homogenous turbulence and channel flow with different Mach numbers and Reynolds numbers are employed to assess the dispersion and dissipation relation of WENO-OS4 scheme. And the shock wave/turbulent boundary layer interaction is directly simulated to access the ability of WENO-OS4 of simulating complex compressible turbulence with large-scale separation. The detailed turbulent structures and the shock waves are obtained. The mean profiles and other statistical data are precisely computed. This study demonstrates the capability of the WENO-OS4 and other optimized WENO scheme for DNS of compressible turbulence.
Journal of Physics: Conference Series, Feb 1, 2021
Aimed at decreasing the numerical dissipation of weighted non-oscillatory and non-free-parameter ... more Aimed at decreasing the numerical dissipation of weighted non-oscillatory and non-free-parameter dissipation (WNND) scheme, we present an improved counterpart for shock-capturing. The new algorithm is based on the framework of Z-type weighting procedure with new local and global smoothness indicators. The performances of the proposed scheme are evaluated on several numerical tests governed by one-dimensional Euler equations. Numerical results indicate that the improved WNND scheme has advantages over the original WNND and third-order WENO-JS and WENO-Z schemes.
Since the first introduction of the weighted essentially non-oscillatory (WENO) scheme in [1], th... more Since the first introduction of the weighted essentially non-oscillatory (WENO) scheme in [1], the efficient implementation in [2] made the algorithm applicable to realistic problems. Despite the success, some analytic outcomes of the scheme were still called in question. It were Henrick et al. [3] who first pointed out that WENO5 failed to pertain the fifth-order accuracy at the critical point where f′ j = 0. They further proposed the necessary and sufficient conditions for a scheme to obtain the order. In order to provide remedies for WENO5, Henrick et al. [3] proposed a carefully designed mapping function, through which the difference between the nonlinear weight and its linear counterpart will usually have the order of Δx3. The corresponding scheme was called as WENO-M, and the improvement on resolution was shown through the comparison with WENO5.
Atomically dispersing metal atoms on supports provides an ideal strategy for maximizing metal uti... more Atomically dispersing metal atoms on supports provides an ideal strategy for maximizing metal utilization for catalysis, which is particularly important for fabricating cost‐effective catalysts based on Earth‐scarce metals. However, due to the high surface energy and thus instability of single atoms, it remains challenging to fabricate stable atomically dispersed metal catalysts. Here, strategies for stabilizing atomically dispersed metal catalysts on various supports are summarized. Based on strategies to enhance the interaction between the metal and the support to prevent the sintering of metal atoms, several approaches to stabilize supported atomically dispersed metal catalysts are then extensively discussed. To close, the importance of the interface species surrounding single atoms in determining the catalytic properties of atomically dispersed metal catalysts is discussed, together with a summary of the prospects for the development of the field.
International Journal for Numerical Methods in Fluids, Jul 4, 2020
SummaryIn this article, we present two improved third‐order weighted essentially nonoscillatory (... more SummaryIn this article, we present two improved third‐order weighted essentially nonoscillatory (WENO) schemes for recovering their design‐order near first‐order critical points. The schemes are constructed in the framework of third‐order WENO‐Z scheme. Two new global smoothness indicators, τL3 and τL4, are devised by a nonlinear combination of local smoothness indicators (ISk) and reference values (ISG) based on Lagrangian interpolation polynomial. The performances of the proposed schemes are evaluated on several numerical tests governed by one‐dimensional linear advection equation or one‐ and two‐dimensional Euler equations. Numerical results indicate that the presented schemes provide less dissipation and higher resolution than the original WENO3‐JS and subsequent WENO3‐N scheme.
Abstract In this paper, the performance of the optimized symmetric fourth-order weighted essentia... more Abstract In this paper, the performance of the optimized symmetric fourth-order weighted essentially non-oscillatory scheme (WENO-OS4) in direct numerical simulation of compressible turbulence is demonstrated and compared with other three optimized WENO schemes. The compressible homogenous turbulence and channel flow with different Mach numbers and Reynolds numbers are employed to assess the dispersion and dissipation relation of WENO-OS4 scheme. And the shock wave/turbulent boundary layer interaction is directly simulated to access the ability of WENO-OS4 of simulating complex compressible turbulence with large-scale separation. The detailed turbulent structures and the shock waves are obtained. The mean profiles and other statistical data are precisely computed. This study demonstrates the capability of the WENO-OS4 and other optimized WENO scheme for DNS of compressible turbulence.
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Papers by Pengxin Liu