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#1 |
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I have a problem with cavitation. The pressure dependent density description for the liquid works fine as long as I do not activate cavitation. But when activating the cavitation I get NaN for the produced species in the first Iteration (although there is no cavitation at the beginning of the simulation at all).
As I using the cavitation model,density of the heavy fluid just can be set as a constant number.Can I using some method to solve this problem? |
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#2 |
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hi generally speaking when you get NaN; it means you are dividing by zero ( or a very small number ) or you are trying to take the root of a negative number - of course if we exclude the case that you are using a value without initailization - here are some Hints:
1- try to use a debugger ( i.e. ddd if your code is in c++ ); this will help you to locate the location of the problem. 2- If the above does not help, I suggest that you examine carefully the places where you interpolate flow variables ( wether the pressure or the temperature is wrongly negative ). 3- look at the bright side ![]() at least you know that your problem is related to cavitation, you don't have to search anywhere else! Go directly to the place that handles this term. 4- when you find the place where the error occurs, try to put =>some kind of a limiter<= to avoid the ( non-positivity ). Hoping it would help . . . good luck ![]() |
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#3 |
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hi, i'll like to know more about cavitation
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