Ignition delay

salmicci · July 12, 2019, 09:13

Good morning everyone,
I am dealing with a methane engine, homogeneous fuel distribution, simulating the ignition and combustion phase (630 deg - 760 deg). Mixture is poor, lambda = 1.5529. I am trying to create a suitable model, so trying pressure and apparent heat release to match with experimental data. My problem is that the pressure (and consequently AHR) raises too late, and reaches low peak values with respect to experimental case.
I think the problem is in the Laminar flame speed.

My questions are:

1. is it correct to use Gülder correlation in case of methane with lambda = 1.5529? Should I change any coefficient of the model? Can the problem be caused by settings in ISSIM ignition model?
2. is there a way to plot laminar flame speed as a function of crank angle in STAR-CD?

My setup:
ECFM-3Z (ISSIM ignition with 0.1 J energy)
CH4 fuel premixed
Adiabatic BC for the electrodes

p.jpg
ahr.jpg

Thank you in advance, Salvo

alpie · October 22, 2019, 15:14

Have you in the meantime resolved the issue you describe here?

July 12, 2019, 09:13	Ignition delay	#1
salmicci New Member Salvo Miccichè Join Date: Jul 2019 Location: Karlsruhe Posts: 1 Rep Power: 0	Good morning everyone, I am dealing with a methane engine, homogeneous fuel distribution, simulating the ignition and combustion phase (630 deg - 760 deg). Mixture is poor, lambda = 1.5529. I am trying to create a suitable model, so trying pressure and apparent heat release to match with experimental data. My problem is that the pressure (and consequently AHR) raises too late, and reaches low peak values with respect to experimental case. I think the problem is in the Laminar flame speed. My questions are: 1. is it correct to use Gülder correlation in case of methane with lambda = 1.5529? Should I change any coefficient of the model? Can the problem be caused by settings in ISSIM ignition model? 2. is there a way to plot laminar flame speed as a function of crank angle in STAR-CD? My setup: ECFM-3Z (ISSIM ignition with 0.1 J energy) CH4 fuel premixed Adiabatic BC for the electrodes p.jpg ahr.jpg Thank you in advance, Salvo

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Combustion Simulation ANSYS Fluent - There is no ignition delay	Rudolf Diesel	FLUENT	1	May 21, 2023 06:30
RCCI model ignition delay	Gaurav0990	CONVERGE	3	July 23, 2021 00:50
Combustion Simulation ANSYS Fluent - There is no ignition delay	Rudolf Diesel	FLUENT	2	October 1, 2018 01:16
Need ignition delay and reaction rate data	ankitraut27	CONVERGE	1	November 7, 2017 15:28
Ignition modeling	Julie Polyakh	Siemens	0	May 20, 2004 08:05

October 22, 2019, 15:14		#2
alpie New Member Join Date: Oct 2019 Posts: 5 Rep Power: 6	Have you in the meantime resolved the issue you describe here?