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lee ho boon April 15, 2002 02:53

problem:case331,two stroke loop scavenge cycle 3D
Having problem with case(331) two stroke loop scavenge cycle 3D

hai, i am currently trying to understand the q1 file of case 331.I am planning to modify this case to simulate a piston pump.just pumping natural gas from one inlet then to one outlet.the transfer port will be the inlet and exhaust port will be the outlet. This is some of my problem. 1)VOLF, WHAT SHOULD I PUT HERE?? 2)in the code it says **exhaust port opens at 70 deg BBDC A1=-70 this one i think i know what is going on but the next line is **end of simulation 1 deg ABDC AN=30,why AN=30??? 3)Under group 9 properties of the medium. Original code simulate two kind of gasses in the cylinder. But my intention to simulate only natural gas flowing in and out of the piston pump. should i do anything there?? 4)the result i like to get from the simulation is to know the ablity of the piston pump to deliver a specific amount(11.8ml) of natural gas under very short time under various RPM.can modification of this code do it??

thanks a lot

Jeremy Wu April 24, 2002 11:14

Re: problem:case331,two stroke loop scavenge cycle

I understand that you have made the similar enquiry to CHAM through Cybron.

1) VOLF is used to estimate a average flow rate in the cylinder which used only for setting RESREF. You can use the same value if you do not have any idea what is the flow movement in the cylinder. 2) AN is the end of angle which defines the piston position. The total piston movement is 100 degree in case 331. 3) I only see two kind of gasses in terms of temperature, but it is still simple phase. You do not need to anything there. But you need to set the properties corresponding to CH4. 4) Yes, you can. I have to change time step size accordingly.

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