## General Mechanical

Topics relate to Mechanical Enterprise, Motion, Additive Print and more

#### View factor calculation in parallel mode

• Antonio Zamora
Subscriber

Hello,

I am building a model where I have defined several closed enclosure radiation boundary conditions. I have been reading at Mechanical APDL Command and Theory Reference about the view factor calculation and I am interested in using the view factor condensation.

As far I know, the VFCO command defines the level of view factor condensation and then, the view factor matrix should be generated by VFOPT,NEW or by SOLVE. As it is written at the VFOPT Command Reference:

------------------------------------------------------------------------------------------------------------------------------------------------------------------

For 3-D analyses, two options are available for calculating view factors when running Distributed Ansys:

• Issue a SOLVE command -- View factors are calculated in parallel mode if no view factors were previously calculated.

• Issue a VFOPT,NEW command -- View factors are calculated in serial mode.

https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v221/en/ans_cmd/Hlp_C_VFOPT.html?q=vf

------------------------------------------------------------------------------------------------------------------------------------------------------------------

The matter is that it seems that the only way to trigger the calculation of the view factor matrix with condensation is with an argument in the VFOPT command (VFOPT,NEW,,,,,,ON), which will be performed in serial mode.

So, my question is:

Anyone knows if there is any way to perform the view factor condensed matrix in parallel mode? For my simulation purpose, it will be great to use the condensed view factor matrix but calculate it in serial mode would weigh down the simulation time.

Best regards,

Antonio Zamora.

• Dave Looman
Ansys Employee

It could be the condensation code hasn't been parallelized.  I'll check.  Is decimation (RDEC) an alternative?

• Antonio Zamora
Subscriber

Yes, decimation could be an option but I was wondering if the condensed matrix could be calculated in parallel mode.

Anyway, thank you for your help.

• Dave Looman
Ansys Employee

Developer suggested issuing VFCO command without VFOPT.