September 10, 2019 at 8:06 ammaliuzairSubscriber
September 10, 2019 at 8:13 am
September 10, 2019 at 9:58 amRobAnsys Employee
Turn the reactions off and see how it behaves. If the reaction rate is UDF controlled what stops it pulling heat from a cell if (for example) activation energy is reached?
September 10, 2019 at 2:50 pm
September 10, 2019 at 4:17 pmRobAnsys Employee
Steady or transient? What do the residuals look like?
September 10, 2019 at 4:23 pm
September 11, 2019 at 9:08 amRobAnsys Employee
It looks like a rogue hot spot, so may be convergence/gradient related. How's the volume fraction of solids looking? You will probably need to turn off one of the granular phases to see how that behaves then gradually make the model more complex: that's our approach when we work through models from commercial clients.
September 11, 2019 at 9:52 ammaliuzairSubscriber
simulations without reactions converge easily.
the pics of volume fractions are attached. one is volume fraction of sand with bubbles. and the other is the species of the phase for which I am having issues.
My approach for simulations was.:
first I patched sand. NO biomass.
solve for flow and volume fraction.
September 11, 2019 at 12:53 pmRobAnsys Employee
Looks sensible, so we (you) need to focus on the phase change & reaction rate.
October 8, 2019 at 5:27 pmmaliuzairSubscriber
Is the temperature limited problem the analogous to reverse flow?
I am asking because the temperature limited problem emerges in some cells and then vanishes, and then reappears just like reversible flow appears and vanishes in cold flows (and doesn't affect the solution in general)
October 10, 2019 at 11:22 amRobAnsys Employee
Yes and no. It's when something causes the solver to increase/decrease the temperature too far. With phase change it's usually that too much material changes phase in one cell and there's not enough energy available to do that. Ideally once the model is running the warnings disappear.
October 15, 2019 at 2:55 pmmaliuzairSubscriber
Another question related to my problem but not related to the topic.
Can we use velocity inlet and mass flow inlet simultaneously? are they compatible?
October 16, 2019 at 10:59 amRobAnsys Employee
Not on the same boundary, but yes you can in the same model.
October 1, 2020 at 6:56 pmHesam062SubscriberHi Maliuzair,nDid you solve the problem of Temperature limitation?nI've got the same issue during simulation of biomass gasification in fluidized bed
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