ET Workshop Fall 2011 EOS

EOS

Discussion about which EOS interfaces Cactus has/had:

• EOS_Base
• EOSG_Base
• EOS_Omni

Who uses what:

• EOS_Omni: ET
• EOSG_Base: "nobody" -> to be archived
• EOS_Base: GaTech code, Whisky_Exp -> to remain, but will be dropped from the ET thornlist
• some version of Whisky has "own" interface to tabulated EOS

MHD

• MHD-Con2Prim assumes polytrope EOS
• Code in Wiki: is general, works for polytrope, ideal gas, and hybrid EOSs
• Josh: implementation of C2P for general EOS is now written for the "General" EOS, case, with th "Polytype" coming soon
• Josh: Some functions are not be fully implemented for the non-polytropic EOS_Omni code, but not critical, mostly atmosphere-related functions

Christian:

• To fix: single NS case for hot EOS
• handle multiple composition evolutions, requires EOS tweaks
• more important working EOS + MHD

MHD Con2Prim

To perform Conservative to Primitive variable conversion in MHD for a generic EOS, we need to use code that is not dependent on the adiabatic index, since it will not be constant. Some notes describing a possible way to implement a more generic Newton-Raphson routine have been uploaded, along with some code to perform this task.

Notes: File:Con2prim eosomni.pdf

Code: File:GRHydro Con2PrimM pt.c