[dwnzng]

I am simulating SLM of basalt on ansys fluent and I want to write a UDF which says that the density before melting 1810, the density during the liquid state is 2760, and the density after resolidification is 2704. Originally I had created a variable "melted" to track whether the sample has already been melted, and thus the density would depend on both temperature and the melted variable. However, because the function is called from scratch every iteration, the melted variable is not stored anywhere and my function doesn't work. I also don't think it's possible to code it based on time because not all elements melt at the same time. I've attached a screenshot of my code so far, is there any other way to make my vision work? Screenshot 2023-07-06 145940.png

[CFDKareem]

Is there a reason you are trying to do this with a UDF rather than a piecewise equation in the materials GUI?

[dwnzng]

Thanks for the reply, I am using a UDF because the initial density of 1810 has a temperature range of 300K - 1450K, but the resolidified density at the end of 2704 has the same temperature range, so I didn't think that was possible to do using the materials GUI

[AlexanderZ]

you may use user defined memory to store flag
C_UDMI(c,t,0) = value

change melting variable to C_UDMI(c,t,0).
allocate user defined memory location = 1 at fluent GUI

next time put the code here, so It could be modified


on the other hand, you may use piecewise equation for this simulations, as was suggested