AnsweredAssumed Answered

Low flow between rotating region and rest fluid volume in tank

Question asked by Zenon Grucha on Jan 29, 2019

Hello everybody,

I have problem with rotational region. There is no flow or very very small flow between rotational region and rest of the fluid:

1.jpgI know this mixer should perform flow on quite large distance (I've got TBM 18,5 veriant stirrer - encircled below, so it should be aprox 90m range with some rpm):



I’ve tried to change rotational region

- bigger:


- smaller:



and there is the same story.


I have large tank (aprox. 120x35x4m):


4.jpg4_5.jpgand some stirrer (aprox 800 mm diameter):



Initial mesh I’ve tried on levels 1,2,3,4 and 5, with 0,001m min gap and 0,003m wall thickness or without manual these manual gaps and there is the same story. Fluid is water, analysis is internal flow. Solver is working fine etc. I’ve tried also different speeds of the rotor – from 300 to 4000 rpm, almost the same story. There is almost no difference if it have local initial mesh area or without it. Anyone know what the problem is?


Thank you in advance,
Marian - student from Poland