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No steep rise in pressure curve

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Old   March 16, 2015, 22:34
Default No steep rise in pressure curve
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Balaji
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I am currently simulating HCCI Mode of Combustion with n - heptane as the fuel. My problem is that I am unable to get a steep rise in the pressure curve although I have a considerable amount of heat release (perceived from the spd file) I have given the following parameters as the input

1. combustion model - ECFM-3Z
2. Cetane no - 60
3. Eq ratio - 0.29
4. EGR - 0%
5. Initial Pressure - 6.14 bar
6. Initial Temp - 503K
7. Injected Mass - 4.716e-4 kg/s (pls tell me whether this mass is sufficient for combustion or not)


Should I need to change any of the ignition parameters?
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Old   March 19, 2015, 02:42
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Hi,
Firstly, what is your injector hole diameter? You should write its diameter values as meter (m) in Pro-Star.
And I guess eq ratio should be bigger, for example 0.85. I usually use Lambda value for air/fuel mixture.(Lambda = 1.5-1.8 for diesel engines).
I am not sure about the mass of injected fuel. Maybe you should check it by using 1D simulation.

Quote:
Originally Posted by srivathsanpoyyapakkam View Post
I am currently simulating HCCI Mode of Combustion with n - heptane as the fuel. My problem is that I am unable to get a steep rise in the pressure curve although I have a considerable amount of heat release (perceived from the spd file) I have given the following parameters as the input

1. combustion model - ECFM-3Z
2. Cetane no - 60
3. Eq ratio - 0.29
4. EGR - 0%
5. Initial Pressure - 6.14 bar
6. Initial Temp - 503K
7. Injected Mass - 4.716e-4 kg/s (pls tell me whether this mass is sufficient for combustion or not)


Should I need to change any of the ignition parameters?
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Old   March 19, 2015, 03:05
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Balaji
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Hi,

Thanks for the reply. My injector hole diameter is 0.188mm. I have found out that my injection mass was not sufficient for combustion.

Can you please help me in deciding the ignition model ?
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Old   March 19, 2015, 03:44
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Can
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I will try. what do you need?

Quote:
Originally Posted by srivathsanpoyyapakkam View Post
Hi,

Thanks for the reply. My injector hole diameter is 0.188mm. I have found out that my injection mass was not sufficient for combustion.

Can you please help me in deciding the ignition model ?
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