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pradeepjp November 24, 2018 15:21

closed cycle diesel combustion
 
Is it required to use parcel simulation in closed cycle (compression and combustion stroke) diesel engine simulation..

kindly help me thru the simulation steps..

SamWijey November 27, 2018 20:24

Hello,

Yes, it is necessary if you want to inject Diesel in to the combustion chamber. Please check our diesel sector example case in v2.4 Studio to learn how to do this. This is a closed cycle simulation.

Thanks,

pradeepjp November 28, 2018 01:20

1 Attachment(s)
Thank you for your response. But consider it a port fuel diesel injection and am trying to simulate only compression and combustion stroke with a closed geometry (attached file). How to define case setup for this problem?

SamWijey November 28, 2018 08:41

Hello,

If you want to assume that the fuel is completely premixed at IVC, then you do not have to use a spray simulation. You simply specify the gas composition (which should be a mixture of oxidizer, fuel and any diluent) at IVC. There is a Dual Fuel engine sector example case in Studio where we assume that NG is premixed at IVC while Diesel is directly injected. Look at the NG premixed part and ignore the diesel injection.

Hope this helps,

Thanks,

pradeepjp December 4, 2018 07:24

Thank you very much sir. I proceeded accordingly but since i have only one region (cylinder, head and piston) with no events involved, I couldnt validate the events tab. how to proceed further?

tmburton December 4, 2018 09:54

Hello,

You don't need events enabled if you only have one region.

Best regards,

Tristan

pradeep6890 January 22, 2019 10:02

CR problem
 
1 Attachment(s)
Thank you sir. I validated all as per your suggestion. but while checking the compression ratio it is showing 1.1 where the target is 17.5? i have attached file for your reference.

nitesh.attal January 22, 2019 10:11

Quote:

Originally Posted by pradeep6890 (Post 722625)
Thank you sir. I validated all as per your suggestion. but while checking the compression ratio it is showing 1.1 where the target is 17.5? i have attached file for your reference.


Please check if you have imported the geometry in correct units (m), e.g. measure the length of your liner in the imported geometry.
You can use the transform->scale-> entire domain feature in STUDIO to apply appropriate scaling factor.

Thanks,

pradeep6890 March 7, 2019 11:03

2 Attachment(s)
Thank you sir. I proceeded accordingly but the pressure values are quite abnormal compared to the experimental values. I have herewith enclosed the pics for your reference. Where am I being wrong? kindly provide your valuable suggestions.

mohsinmkhan March 9, 2019 13:05

Quote:

Originally Posted by pradeep6890 (Post 722625)
Thank you sir. I validated all as per your suggestion. but while checking the compression ratio it is showing 1.1 where the target is 17.5? i have attached file for your reference.

you have to follow tutorial videos for achieving target compression ratio. make sure you got right current compression ratio

mohsinmkhan March 9, 2019 13:07

Quote:

Originally Posted by SamWijey (Post 717174)
Hello,

If you want to assume that the fuel is completely premixed at IVC, then you do not have to use a spray simulation. You simply specify the gas composition (which should be a mixture of oxidizer, fuel and any diluent) at IVC. There is a Dual Fuel engine sector example case in Studio where we assume that NG is premixed at IVC while Diesel is directly injected. Look at the NG premixed part and ignore the diesel injection.

Hope this helps,

Thanks,

But is this the right way of assuming it as premixed... because it would not provide results within 10% error margin....?


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