Recent progress in MICRESS development
Posted: Mon Jun 23, 2008 8:30 am
Hi all!
Even shortly after Release 5.3 we have already made further development on the MICRESS code! These changes will be officially released with the next version, but a beta version is available on request to our customers.
One of the mayor changes after 5.3 is, that the enthalpies of the phases are now directly calculated by TQ if a thermodynamic database is used. Enthalpies are used only for latent heat release, so these changes apply only to cases where latent heat is implied. MICRESS users dealing with release of latent heat, or planning to do so, should definitively ask us for the beta version! The formerly used approximation of a constant user-defined latent heat is typically quite far from reality and should be avoided, if realistic latent heat production is of importance.
Also, quite a bit of work has been invested into the coupling to a one-dimensional temperature field (1d_temp). This approach is interesting if neither the approximation of integral release of latent heat and a small thermal gradient, nor the approximation of a strong thermal gradient and neglection of latent heat are viable. The 1D temperature field can be defined in cartesian, cylindrical or polar coordinates and exchanges heat due to the enthalpy change in the simulation domain as well as via the upper and lower boundary condition. As it can be defined with considerably lower resolution compared to normal simulation domain, it can be easily used e.g. in the macroscopic dimensions of the casting geometry.
Although the possibility of coupling to a 1D temperature field is already (inofficially) included into the Release 5.3, it has been reworked completely, and now also benefits from the direct access to the enthalpies from the database.
Apart from the above mayor changes, there have been a lot of small improvements, especially the further optimization of the thermodynamic coupling with new stability control outputs and enhanced numerical checks for stoichiometric phases.
The option to use more than 10 memory segments, i.e. to use more phases and phase interactions with coupling to thermodynamic data, was already added for the Release 5.3, thanks to our partners at Thermo-Calc Softwase AB. But, after 5.3, an additional rework of the redistribution routines was done to improve performance, if many phases (>10) are used. Now, there is also the possibility to define several MICRESS phases for the same phase description in the database: For example, in hypereutectic aluminium alloys primary and eutectic silicon can be treated as two different phases!
This list is to be continued!
Bernd
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original message from Bernd
Even shortly after Release 5.3 we have already made further development on the MICRESS code! These changes will be officially released with the next version, but a beta version is available on request to our customers.
One of the mayor changes after 5.3 is, that the enthalpies of the phases are now directly calculated by TQ if a thermodynamic database is used. Enthalpies are used only for latent heat release, so these changes apply only to cases where latent heat is implied. MICRESS users dealing with release of latent heat, or planning to do so, should definitively ask us for the beta version! The formerly used approximation of a constant user-defined latent heat is typically quite far from reality and should be avoided, if realistic latent heat production is of importance.
Also, quite a bit of work has been invested into the coupling to a one-dimensional temperature field (1d_temp). This approach is interesting if neither the approximation of integral release of latent heat and a small thermal gradient, nor the approximation of a strong thermal gradient and neglection of latent heat are viable. The 1D temperature field can be defined in cartesian, cylindrical or polar coordinates and exchanges heat due to the enthalpy change in the simulation domain as well as via the upper and lower boundary condition. As it can be defined with considerably lower resolution compared to normal simulation domain, it can be easily used e.g. in the macroscopic dimensions of the casting geometry.
Although the possibility of coupling to a 1D temperature field is already (inofficially) included into the Release 5.3, it has been reworked completely, and now also benefits from the direct access to the enthalpies from the database.
Apart from the above mayor changes, there have been a lot of small improvements, especially the further optimization of the thermodynamic coupling with new stability control outputs and enhanced numerical checks for stoichiometric phases.
The option to use more than 10 memory segments, i.e. to use more phases and phase interactions with coupling to thermodynamic data, was already added for the Release 5.3, thanks to our partners at Thermo-Calc Softwase AB. But, after 5.3, an additional rework of the redistribution routines was done to improve performance, if many phases (>10) are used. Now, there is also the possibility to define several MICRESS phases for the same phase description in the database: For example, in hypereutectic aluminium alloys primary and eutectic silicon can be treated as two different phases!
This list is to be continued!
Bernd
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original message from Bernd