Dear All,

I need to use fix msst to calculate p-v curve of beta-HMX. Can I get the curve in one simulation?If not, how can I get a complete curve using fix msst? Thanks a lot for your reply.

Guangyu

I suppose by “p-v curve” you mean Hugoniot in the p-v plane? If yes, then it is not a “curve” but a locus of data points…

Anyway, you can only get one data point on the Hugoniot plane from one simulation. To get a complete Hugoniot using fix msst, you will have run a series of simulations with different shock velocities.

Ray

Ray,

The p-v curve means the locus path of p-v during compression of HMX. If fix msst can simulate the compression of HMX, how come I need to do a series of simulation? Thanks for your reply.

Guangyu

Fix msst, with a specific shock velocity, takes the system to ONE specific Hugoniot state (meaning one point on any plane).

If you have more questions, you need to read text books and/or articles on shock physics.

Ray

Ray,

Thanks for your advice.

Guangyu

Ray,

When I use fix msst to compress HMX, for example, I set the shock velocity to be 9000 m/s. I got the log file and calculate the velocity of deformation, found them close to 9000 m/s at first but then they decreased to like 700 or 800 m/s. So do I need to control the deformation history and keep them at 9400 m/s or it is just a normal phenomenon existing in simulation using fix msst? Thanks.

Guangyu

You should read the MSST paper (by Reed et al) to educate yourself on this technique. This mailing list is no substitution for that.

Ray