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Ankur March 8, 2008 02:37

Ignition timing for diesel combustion
 
Is it necessary to specify ignition timing for diesel combustion simulation.

usker March 8, 2008 07:29

Re: Ignition timing for diesel combustion
 
Please elaborate, what exactly do you mean?

Pauli March 8, 2008 11:13

Re: Ignition timing for diesel combustion
 
No. You specify injection timing.

Andrea March 9, 2008 21:26

Re: Ignition timing for diesel combustion
 
Copy, you specify injection timing and second you can "influence" the injection timing...but it depends on the combustion model that you use:
- if you use a model associated with the Shell ingnition model you specify some ignition characteristic such as characteristic temperature, cetane number, etc.
- if you use comb. model from the ECFM family you can define only the cetane number and by means of that you can vary the time of combustion

Ankur March 10, 2008 00:44

Re: Ignition timing for diesel combustion
 
I am using shell auto ignition model and default value used is 1100K.Is it correct?

Andrea March 15, 2008 21:18

Re: Ignition timing for diesel combustion
 
Yes it is correct, you can try to vary the start of injection by means of the costant AF04 of the model. Try to vary it (by means of posdat.f for example)...a value of 2.5e6 may be a good fist attempt to match the correct ignition time


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