Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 3 of 3
Full-Text Articles in Physical Sciences and Mathematics
High Order Entropy Conservative Central Schemes For Wide Ranges Of Compressible Gas Dynamics And Mhd Flows, Björn Sjögreen, H.C. Yee
High Order Entropy Conservative Central Schemes For Wide Ranges Of Compressible Gas Dynamics And Mhd Flows, Björn Sjögreen, H.C. Yee
United States National Aeronautics and Space Administration: Publications
The Sjogreen and Yee [31]high order entropy conservative numerical method for compressible gas dynamics is extended to include discontinuities and also extended to equations of ideal magnetohydrodynamics (MHD). The basic idea is based on Tadmor’s [40]original work for inviscid perfect gas flows. For the MHD four formulations of the MHD are considered: (a) the conservative MHD, (b) the Godunov [14]non-conservative form, (c) the Janhunen [19]– MHD with magnetic field source terms, and (d) a MHD with source terms by Brackbill and Barnes[5]. Three forms of the high order entropy numerical fluxes for the MHD in the finite difference framework are …
Groundwater Withdrawals Under Drought: Reconciling Grace And Land Surface Models In The United States High Plains Aquifer, Wanshu Nie, Benjamin Zaitchik, Matthew Rodell, Sujay V. Kumar, Martha C. Anderson, Christopher Hain
Groundwater Withdrawals Under Drought: Reconciling Grace And Land Surface Models In The United States High Plains Aquifer, Wanshu Nie, Benjamin Zaitchik, Matthew Rodell, Sujay V. Kumar, Martha C. Anderson, Christopher Hain
United States National Aeronautics and Space Administration: Publications
Advanced Land Surface Models (LSM) offer a powerful tool for studying hydrological variability. Highly managed systems, however, present a challenge for these models, which typically have simplified or incomplete representations of human water use. Here we examine recent groundwater declines in the US High Plains Aquifer (HPA), a region that is heavily utilized for irrigation and that is also affected by episodic drought. To understand observed decline in groundwater and terrestrial water storage during a recent multiyear drought, we modify the Noah-MP LSM to include a groundwater irrigation scheme. To account for seasonal and interannual variability in active irrigated area, …
Two Decades Old Entropy Stable Method For The Euler Equations Revisited, Björn Sjögreen, H. C. Yee
Two Decades Old Entropy Stable Method For The Euler Equations Revisited, Björn Sjögreen, H. C. Yee
United States National Aeronautics and Space Administration: Publications
The two decades old high order central differencing via entropy splitting and summation-by-parts (SBP) difference closure of Olsson and Oliger, Gerritsen and Olsson, and Yee et al. [2, 7, 25] is revisited. The entropy splitting is a form of skewsymmetric splitting in terms of the physical entropy of the nonlinear Euler flux derivatives. Central differencing applied to the entropy splitting form of the Euler flux derivatives together with SBP difference operators will, hereafter, be referred to as entropy split schemes.