calculate plastic dissipation based on M_p not S

src/phase.f90

@@ -196,6 +196,10 @@ module phase
       real(pReal), dimension(3,3) :: F_e
     end function mechanical_F_e
 
+    module function mechanical_F_i(ph,en) result(F_i)
+      integer, intent(in) :: ph,en
+      real(pReal), dimension(3,3) :: F_i
+    end function mechanical_F_i
 
     module function phase_F(co,ce) result(F)
       integer, intent(in) :: co, ce

src/phase_mechanical.f90

@@ -1319,6 +1319,20 @@ module function mechanical_F_e(ph,en) result(F_e)
 end function mechanical_F_e
 
 
+!--------------------------------------------------------------------------------------------------
+!< @brief Get eigen deformation gradient (for use by non-mech physics).
+!--------------------------------------------------------------------------------------------------
+module function mechanical_F_i(ph,en) result(F_i)
+
+  integer, intent(in) :: ph,en
+  real(pReal), dimension(3,3) :: F_i
+
+
+  F_i = phase_mechanical_Fi(ph)%data(1:3,1:3,en)
+
+end function mechanical_F_i
+
+
 !--------------------------------------------------------------------------------------------------
 !< @brief Get second Piola-Kirchhoff stress (for use by homogenization).
 !--------------------------------------------------------------------------------------------------

src/phase_thermal_dissipation.f90

@@ -1,6 +1,7 @@
 !--------------------------------------------------------------------------------------------------
 !> @author Martin Diehl, Max-Planck-Institut für Eisenforschung GmbH
 !> @author Pratheek Shanthraj, Max-Planck-Institut für Eisenforschung GmbH
+!> @author Franz Roters, Max-Planck-Institut für Eisenforschung GmbH
 !> @brief material subroutine for thermal source due to plastic dissipation
 !> @details to be done
 !--------------------------------------------------------------------------------------------------
@@ -77,10 +78,13 @@ module function dissipation_f_T(ph,en) result(f_T)
   integer, intent(in) :: ph, en
   real(pReal) :: &
     f_T
+  real(pReal), dimension(3,3) :: &
+    Mp                                                                                              !< Mandel stress work conjugate with Lp
 
+  Mp = matmul(matmul(transpose(mechanical_F_i(ph,en)),mechanical_F_i(ph,en)),mechanical_S(ph,en))
 
   associate(prm => param(ph))
-    f_T = prm%kappa*sum(abs(mechanical_S(ph,en)*mechanical_L_p(ph,en)))
+    f_T = prm%kappa*sum(abs(Mp*mechanical_L_p(ph,en)))
   end associate
 
 end function dissipation_f_T