[mohsinmkhan]

If air is coming through intake manifold and gas is injecting through injector during compression stroke,then in GAS SIMULATION part of case setup which therm.dat file we have to provide? and also do we have to provide transport.dat file or gas.dat file?

[ksrivast]

Hello Mohsin,

The file therm.dat is a database file consisting of species-specific thermodynamic data. You would need to ensure that all the species being used in your simulation have an entry available in therm.dat . For example, thermodynamic data for O2, N2 coming from intake and H2 injected into the cylinder, and any intermediate species if combustion is turned on, should all be present in a single therm.dat file.

The choice of transport.dat or gas.dat depends on the role of molecular diffusion. For an IC engine, turbulent diffusion is much more dominant than molecular diffusion, and thus gas.dat is sufficient, where diffusion coefficients are calculated independent of species concentration. Systems with laminar flame applications employ transport.dat.

Please refer to our manual for detailed information on these files. There are sample therm.dat and gas.dat available in STUDIO. Since therm.dat and transport.dat are of standard format, you can find them online or get in touch with us.

Sincerely,

[mohsinmkhan]

Originally Posted by ksrivast

Hello Mohsin,

The file therm.dat is a database file consisting of species-specific thermodynamic data. You would need to ensure that all the species being used in your simulation have an entry available in therm.dat . For example, thermodynamic data for O2, N2 coming from intake and H2 injected into the cylinder, and any intermediate species if combustion is turned on, should all be present in a single therm.dat file.

The choice of transport.dat or gas.dat depends on the role of molecular diffusion. For an IC engine, turbulent diffusion is much more dominant than molecular diffusion, and thus gas.dat is sufficient, where diffusion coefficients are calculated independent of species concentration. Systems with laminar flame applications employ transport.dat.

Please refer to our manual for detailed information on these files. There are sample therm.dat and gas.dat available in STUDIO. Since therm.dat and transport.dat are of standard format, you can find them online or get in touch with us.

Sincerely,

& sir for gas.dat do we need to consider air coming from intake manifold or gas which is coming from injector? or it is independent of both?

[ksrivast]

Hello Mohsin,

As stated above, the gas.dat data is independent of species. Provide temperature varying thermal conductivity and viscosity values that will be used to calculate diffusion coefficients regardless of what the species concentrations are or where they come from.

Sincerely,