moving mesh/premix combustion
 

Hello,

Is there anybody who can offer some help to solve a couple of problems in 2-stroke engine simulation.

Please reply,

Sincerely, AJ

Re: moving mesh/premix combustion
 

I'm a post Graduate student from Uni of Moratuwa, SriLanka. I'm doing scavenge flow simulations in 2-strokes using the code "star-cd". If i can be of any assistance, let me know.

Re: moving mesh/premix combustion
 

Hi Sameera,

I have some problem defining premix combustion (Thanks to Mehdi). I get some fraction of product species starting from the beginning. In temperature plots it seems like a flame is propagating in the chamber for which region temperature rise is notable. Do you have any idea of this kind of results?

I get error message for my egrid commands at the very first event of expansion stroke when I load events for one revolution. But in the star run I did not find any error at that crank position. Is it a star-cd BUG? Going further down where ports reattaches to the piston I get same egrid command error and solver gives negative density errors.

I appreciate your enthusiasm.

Re: moving mesh/premix combustion
 

Hi Sameera,

I have some problem defining premix combustion (Thanks to Mehdi). I get some fraction of product species starting from the beginning. In temperature plots it seems like a flame is propagating in the chamber for which region temperature rise is notable. Do you have any idea of this kind of results?

I get error message for my egrid commands at the very first event of expansion stroke when I load events for one revolution. But in the star run I did not find any error at that crank position. Is it a star-cd BUG? Going further down where ports reattached to the piston I get same egrid command error and solver gives negative density errors.

I appreciate your enthusiasm.

Re: moving mesh/premix combustion
 

Hi, Answering your second question regarding the error message that you get (negative density), it may be due to the event commands. Now after completing one up and down stroke, in order for STARCD to continue the same, you need to give an additional time for the subsequent events. Refer to tutorial. Hope this helps.

Re: moving mesh/premix combustion
 

Hello Mac,

Thanks for your reply. I would not try for more than one revolution, especially when I am not able to finish one complete revolution. I get negative density error in the first revolution when cylinder reattaches to the ports as piston moves down.