User: rhaas
Date: 2012/05/16 11:28 AM
Modified:
/trunk/
param.ccl
/trunk/src/
GRHydro_HLLEM.F90
Log:
GRHydro: decouple Bvec(flux_direction) from other two for divclean
since it and psidc form a 2d subsystem of the characteristic system. See
eg. Mignonoe et al. arXiv:1001.2832v2 section 3.1.
File Changes:
Directory: /trunk/src/
======================
File [modified]: GRHydro_HLLEM.F90
Delta lines: +6 -0
===================================================================
--- trunk/src/GRHydro_HLLEM.F90 2012-05-14 18:47:06 UTC (rev 334)
+++ trunk/src/GRHydro_HLLEM.F90 2012-05-16 16:28:21 UTC (rev 335)
@@ -442,6 +442,12 @@
!!$ Wavespeeds for psidc are +/-c, not Fast Magnetosonic?
psidcf = 0.5d0 * (1.d0 * psidcfp - (-1.d0) * psidcfm + &
1.d0 * (-1.d0) * psidcdiff)
+ if(decouple_normal_Bfield .ne. 0) then ! same expression for HLLE and LLF
+ !!$ B^i field decouples from the others and has same propagation
+ !!$ speed as divergence
+ f1(5+flux_direction) = 0.5d0 * (1.d0 * fplus(5+flux_direction) - (-1.d0) * fminus(5+flux_direction) + &
+ 1.d0 * (-1.d0) * qdiff(5+flux_direction))
+ end if
case(2)
charmax = setcharmax
charmin = setcharmin
Directory: /trunk/
==================
File [modified]: param.ccl
Delta lines: +4 -0
===================================================================
--- trunk/param.ccl 2012-05-14 18:47:06 UTC (rev 334)
+++ trunk/param.ccl 2012-05-16 16:28:21 UTC (rev 335)
@@ -549,6 +549,10 @@
-1:0 :: "Any value smaller than speed of light - sign should be negative"
} -1.0
+BOOLEAN decouple_normal_Bfield "when using divergence cleaning properly decouple Bx,psidc subsystem"
+{
+} yes
+
boolean track_divB "Track the magnetic field constraint violations"
{
} "no"