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a student May 18, 2006 04:15

Please help
 
Hello experts,

I have been working on 2-stroke engine simulation. I have found so many difficulties and I have solved some of them.

Is there anybody who wants to answer my stupid questions. I would really appreciate it. Even I am ready to pay whatever it costs if one can take me out of deep s**t. My graduation will be in trouble if I don't finish this. I am not asking to do my simultion. I am just asking for help and proper guidance. my e-mail: apjani@my.lamar.edu

Please reply. Thanking you

Dr C.Bhasker May 19, 2006 02:46

Re: Please help
 
please know me your questions!

a student May 19, 2006 04:23

Re: Please help
 
Dr. Bhasker,

Thank you very much for your reply.

I apologize to all members if I have misbehaved in my previous message.

In 2-stroke engine I get negative density error near the closing of the ports. I have tried to model ports and cylinder attachment with regular sliding motion as well as with arbitrary sliding motion. In both cases I have succeeded once only in each case in getting piston motion pass the ports. In arbitrary sliding method I had whole 360 degree rotation with proper pressure rise but no combustion and in regular, till the reattachment of the ports to the cylinder in expansion stroke with proper pressure rise and combustion. I get products mass fraction before specified ignition time.

I am using propane and air premix stoc. mixture. Boundaries- inlet, attached, pressure intake-u=5,v=5,p=1.0e+05,t=293,turb. inten.=0.1,len. scal=0.0026 exhaust-p=1.0e+05,t=zero grad,turb.inten=0.1,len. scal=0.0026 scalars at intake- c3h8,o2&n2 specified, co2&h2o zero. scalars at exhaust-all zero air-den=idealf(p,t),cp= polinomial of temp pr. under. relax=0.7 differencing scheme- density=cd0.01,rest=mars0.5 dt=0.1deg.

Any kind of help would be life saving.

Bunch of thanks.



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