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In the case of a high-temperature proton exchange membrane fuel cell, the interface inlet conditions for rich mass transfer only define the mass fraction of the components of the inlet gas, and the Brinkmann equation interface only defines the flow rate conditions of the inlet gas. How can I know the absolute amount of the flow into the channel? I think that the boundary conditions are not enough.


1 Reply Last Post 29.01.2019, 04:02 GMT-5
Henrik Ekström COMSOL Employee

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Posted: 6 years ago 29.01.2019, 04:02 GMT-5
Updated: 6 years ago 29.01.2019, 08:21 GMT-5

The issue here is that the density depends on the pressure, which is not known a priori at the inlet.

If you have the CFD module, you can use the Mass flow option on the Inlet boundary node in the Fluid flow interface to set the flow rate in kg/s.

If you do not have access to the CFD Module we may be able to help you set up this boundary condition manually by the use of a global pressure degree of freedom and a pressure inlet condition. Contact support and we'll take it from there.

The issue here is that the density depends on the pressure, which is not known a priori at the inlet. If you have the CFD module, you can use the Mass flow option on the Inlet boundary node in the Fluid flow interface to set the flow rate in kg/s. If you do not have access to the CFD Module we may be able to help you set up this boundary condition manually by the use of a global pressure degree of freedom and a pressure inlet condition. Contact support and we'll take it from there.

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