# Need help in understanding Transient Periodic & Non-Periodic Boundary Conditions

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 May 5, 2017, 00:01 Need help in understanding Transient Periodic & Non-Periodic Boundary Conditions #1 New Member   Sadia Join Date: Oct 2016 Posts: 11 Rep Power: 9 Hello Everyone, I'm working upon ANSYS Fluent for my PG Research Project. I've been studying a lot about the various boundary conditions and thereby trying to apply the boundary conditions as per my project's domain. I'm working upon Transient model for which I could figure out how to model udf as well profile but I've a query: In profile definition in case of tabular transient data there are two options: '0' represents non periodic, & '1' represents periodic. I know periodic means something that repeats itself with respect to time while non periodic does not, but I'm confused how to apply this with respect to my problem and whether what I've been applying is correct or not. Suppose there is a pulsed energy source which applies variable heat flux with respect to time for some time, say, 0.5 milliseconds and then it stays off for the rest of the time, say, 39.5 milliseconds. Now my main query: 1) If for time 0.5-40 milliseconds the value of heat flux is 0, so if I give 0 as heat flux for time 0.5 millisecond and then I give 0 as heat flux for time 40 millisecond, will the Fluent solver take 0 heat flux between 0.5-40 milliseconds? 2) If I give it a single run, i.e., 40 milliseconds, do I have to use '1' or do I have to use '0'? 3) Since the case is of pulsed energy source so I would need to give more than 1 runs as per the rep rate. Mine would probably go for 25 Hz. So, what if I want to repeat the same for the desired rep rate? Would I need to write the same case for each time step or can I use my already defined profile (which i modeled for single pulse, i.e. for 40 millisecond) for the desired rep rate, i.e., 25 Hz? If I can run the 40 millisecond model again n again for 25 Hz without defining it again n again, so how is it done? Thanks!