Start the simulation during a valve event

MMatt · December 6, 2019, 07:45

I am simulating an IC engine with 4 valves (2 intake, 2 exhaust). I want to start the simulation at -540°CA, and the exhaust valve in my case is already open. But when I check on the timing map the exhaust valve event doesn't appear (probably because it starts before the beginning of the simulation).

I've now opened the exhaust valves the correct amount corresponding to -540°CA because I want to start the simulation with the exhaust valve in the proper position.

Is it possible?

MFGT · December 9, 2019, 01:42

I usually start at -540 CA too and thats not a problem.
The timing map often shows incorrect timing for EVO-EVC, but the recognized values from events.in via automatic valve event is correct.

BTW, you can click on each row / bar in the timing map and us the mouse wheel to shift these by cyclic 720CA (only visually).

MMatt · December 9, 2019, 07:50

You are correct! Even if the event doesn't appear on the timing map, looking at the flow rate between the regions shows there is indeed flow there!

MCoil · December 10, 2019, 13:34

So were you able to start your simulation at -540 CAD as desired? If not, post your input files so we can look.
Thanks,

MMatt · December 11, 2019, 02:12

Starting the simulation at -540°CA was not the issue, it was the fact that I thought the exhaust valve didn't open at that time because it was not showing on the timing map, however, looking at the results, the valve is indeed opened at that time.

December 6, 2019, 07:45	Start the simulation during a valve event	#1
MMatt Member MMatt Join Date: May 2013 Posts: 59 Rep Power: 12	I am simulating an IC engine with 4 valves (2 intake, 2 exhaust). I want to start the simulation at -540°CA, and the exhaust valve in my case is already open. But when I check on the timing map the exhaust valve event doesn't appear (probably because it starts before the beginning of the simulation). I've now opened the exhaust valves the correct amount corresponding to -540°CA because I want to start the simulation with the exhaust valve in the proper position. Is it possible?

December 10, 2019, 13:34	Valve motion	#4
MCoil Member Millicent Coil Join Date: Aug 2017 Posts: 38 Rep Power: 8	So were you able to start your simulation at -540 CAD as desired? If not, post your input files so we can look. Thanks, __________________ Millicent Coil Principal Engineer - Applications Convergent Science Madison, WI

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December 9, 2019, 01:42		#2
MFGT Senior Member Tobias Join Date: May 2016 Location: Germany Posts: 264 Rep Power: 10	I usually start at -540 CA too and thats not a problem. The timing map often shows incorrect timing for EVO-EVC, but the recognized values from events.in via automatic valve event is correct. BTW, you can click on each row / bar in the timing map and us the mouse wheel to shift these by cyclic 720CA (only visually).

December 9, 2019, 07:50		#3
MMatt Member MMatt Join Date: May 2013 Posts: 59 Rep Power: 12	You are correct! Even if the event doesn't appear on the timing map, looking at the flow rate between the regions shows there is indeed flow there!

December 11, 2019, 02:12		#5
MMatt Member MMatt Join Date: May 2013 Posts: 59 Rep Power: 12	Starting the simulation at -540°CA was not the issue, it was the fact that I thought the exhaust valve didn't open at that time because it was not showing on the timing map, however, looking at the results, the valve is indeed opened at that time.