COMSOL 6.3 - Energy Variables

The energy variables used in the structural mechanics interfaces are summarized in Table 3-9.

Table 3-9: Energy Variables Used in Structural Mechanics.
Variable	Description	SI Unit	Physics Interface1	Comment
phys.Ws	Elastic strain energy density	J/m3	solid, mbd, shell, plate, mbrn, beam, truss, wire
phys.WsM	Membrane strain energy	J/m2	shell, plate	Contributes to phys.Ws
phys.WsB	Bending strain energy	J/m2	shell, plate	Contributes to phys.Ws
phys.WsS	Shear strain energy	J/m2	shell, plate	Contributes to phys.Ws
phys.WsM	Membrane strain energy	J/m	beam	Contributes to beam.WsL
phys.WsB	Bending strain energy	J/m	beam	Contributes to beam.WsL
phys.WsS	Shear strain energy	J/m	beam	Contributes to beam.WsL
beam.WsT	Torsional strain energy	J/m	beam	Contributes to beam.WsL
phys.WsL	Strain energy density per unit length	J/m	beam, truss	phys.Ws = phys.WsL/area
phys.Ws_tot	Total elastic strain energy	J	solid, mbd, shell, plate, mbrn, beam, truss, wire	Global variable containing integration and summation of all phys.Ws contributions in a physics interface.
phys.Wh	Stored energy density	J/m3	solid, mbd, shell, plate, mbrn, beam, truss, wire	Cycle average in frequency domain of elastic energy density.
phys.WhM	Membrane stored energy	J/m2	shell, plate	Contributes to phys.Wh
phys.WhB	Bending stored energy	J/m2	shell, plate	Contributes to phys.Wh
phys.WhS	Shear stored energy	J/m2	shell, plate	Contributes to phys.Wh
phys.Wh_tot	Total stored energy	J	solid, mbd, shell, plate, mbrn, beam, truss, wire	Global variable containing integration and summation of all phys.Wh contributions in a physics interface.
phys.Wk	Kinetic energy density	J/m3	solid, mbd, shell, plate, mbrn, beam, truss, wire
phys.Wk_tot	Total kinetic energy	J	solid, mbd, shell, plate, mbrn, beam, truss	Global variable containing integration and summation of all phys.Wk contributions in a physics interface.
phys.Wp	Plastic dissipation density	J/m3	solid	Energy density dissipated by plasticity.
phys.Wp_tot	Total plastic dissipation	J	solid	Global variable containing integration and summation of all phys.Wp contributions in a physics interface.
phys.Wc	Creep dissipation density	J/m3	solid	Energy density dissipated by creep.
phys.Wc_tot	Total creep dissipation	J	solid	Global variable containing integration and summation of all phys.Wp contributions in a physics interface.
phys.Wv	Viscoelastic dissipation density	J/m3	solid	Energy density dissipated by viscosity.
phys.Wv_tot	Total viscoelastic dissipation	J	solid	Global variable containing integration and summation of all phys.Wv contributions in a physics interface.
phys.Wdmg	Damage dissipation density	J/m3	solid	Energy density dissipated by damage.
phys.Wdmg_tot	Total damage dissipation	J	solid	Global variable containing integration and summation of all phys.Wdmg contributions in a physics interface.
phys.Wfrac	Fracture energy density	J/m3	solid	Energy density dissipated by phase field damage.
phys.Wfrac_tot	Total fracture energy	J	solid	Global variable containing integration and summation of all phys.Wfrac contributions in a physics interface.
phys.Wed	Dielectric dissipation density	J/m3	solid	Piezoelectric electrical damping.
phys.Wed_tot	Total dielectric dissipation	J	solid	Global variable containing integration and summation of all phys.Wed contributions in a physics interface.
phys.Wmd	Damping dissipation density	J/m3	solid	Piezoelectric mechanical damping
phys.Wmd_tot	Total damping dissipation	J	solid	Global variable containing integration and summation of all phys.Wmd contributions in a physics interface.
phys.Wstb	Dielectric dissipation density	J/m3	solid	Hourglass stabilization energy density.
phys.Wstbavg	Total dielectric dissipation	J/m3	solid	Hourglass stabilization energy density, element average.
phys.Wstb_tot	Total dielectric dissipation	J/m3	solid	Global variable containing integration and summation of all phys.Wstb contributions in a physics interface.
phys.I*	Mechanical energy flux, * coordinate	W/m2	solid, mbd
phys.Icomplex*	Complex mechanical energy flux, *coordinate	W/m2	solid, mbd	Frequency domain only.
1The availability of physics interfaces is based on the license for a module.