# compressibility and cavitation!!

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 March 5, 2005, 22:39 compressibility and cavitation!! #1 xhliu1 Guest   Posts: n/a 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?

 March 14, 2005, 14:17 Re: compressibility and cavitation!! #2 khalid sultan Guest   Posts: n/a 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

 June 27, 2005, 17:16 Re: compressibility and cavitation!! #3 ti Guest   Posts: n/a hi, i'll like to know more about cavitation

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