[LS-DYNA] E0 Initialization

- April 28, 2022 at 5:36 pm
  
  FluxLimited
  Subscriber
  
  I've read over the section in the manual regarding the initialization of E0 for materials with Equations of State. I understand how to do it. But when is it critical to do so? I typically initialize v0 (initial specific volume) to 1.0. I have tried tests with materials and initializing E0 to rho*Cv*T or leaving it at zero does not seem to impact the simulation.
- May 5, 2022 at 3:47 pm
  
  Ram Gopisetti
  Ansys Employee
  
  the internal enrgy is used where there is an thermal pressure and is dependent of volumetric compression and thermal state of an material.
  Cheers, Ram
- May 13, 2022 at 3:39 pm
  
  FluxLimited
  Subscriber
  
  thanks for your help. So if I am running a purely isothermal mechanical problem the value of E0 does not play a role? What about in the JWL EOS? There is no thermal component but I imagine the E0 would play a role in the energy density of explosives.
- July 1, 2022 at 10:56 pm
  
  Jim Day
  Ansys Employee
  
  Yes, E0 would be nonzero in *EOS_JWL when modeling a high explosive. Values may be hard to come by owing to the sensitive nature of modeling HE.
  A fairly common application of E0 in *EOS is to initialize atmospheric pressure in air using *EOS_LINEAR_POLYNOMIAL. Look for the notes on air in the LS-DYNA Aerospace Working Group MGD (Modeling Guidelines Document). Use Google to locate this document.