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### Heat Flux at the surface nodes, CTF vs CFD method

Hi All,

First of all, can we consider "Face Conduction Heat Transfer Rate per Area" on a surface face(inside/outside) in ConductionTransferFunction method same as "Surface Heat Flux" on the boundary nodes of a surface in ConductionFiniteDifference method. Same not in the terms of value but in the terms of meaning and how these both values are calculated in EP.

I am comparing heat flux from an experimental data (DSC) of a specimen with a virtual specimen in EP and in that error results from CTF algorithm looks better than CFD algorithm.

Has anybody experienced this before and if so what can be the reasons?

Thanks

 2 retagged __AmirRoth__ 4388 ●5 ●16 http://bleedinggreenna...

### Heat Flux at the surface nodes, CTF vs CFD method

Hi All,

First of all, can we consider "Face Conduction Heat Transfer Rate per Area" on a surface face(inside/outside) in ConductionTransferFunction method same as "Surface Heat Flux" on the boundary nodes of a surface in ConductionFiniteDifference method. Same not in the terms of value but in the terms of meaning and how these both values are calculated in EP.

I am comparing heat flux from an experimental data (DSC) of a specimen with a virtual specimen in EP and in that error results from CTF algorithm looks better than CFD algorithm.

Has anybody experienced this before and if so what can be the reasons?

Thanks

### Heat Flux at the surface nodes, CTF vs CFD method

Hi All,

First of all, can we consider "Face Conduction Heat Transfer Rate per Area" on a surface face(inside/outside) in ConductionTransferFunction method same as "Surface Heat Flux" on the boundary nodes of a surface in ConductionFiniteDifference method. Same not in the terms of value but in the terms of meaning and how these both values are calculated in EP.

I am comparing heat flux from an experimental data (DSC) of a specimen with a virtual specimen in EP and in that error results from CTF algorithm looks better than CFD algorithm.

Has anybody experienced this before and if so what can be the reasons?

Edit- For more details-

I am simulating a conventional wall, subject to sinusoidal temperature excitation on the outer layer and constant temperature on the inner layer, with both CTF and CFD methods.

I have experimental data for comparison, and results from CTF simulation are much more consistent with experimental data then those with CFD. In particular, the heat flux at the indoor surface with CTF is (as expected) perfectly sinusoidal, while with CFD method it shows quite a large deviation from a perfect sinusoidal.

Thanks

 4 retagged __AmirRoth__ 4388 ●5 ●16 http://bleedinggreenna...

### Heat Flux at the surface nodes, CTF vs CFD method

Hi All,

First of all, can we consider "Face Conduction Heat Transfer Rate per Area" on a surface face(inside/outside) in ConductionTransferFunction method same as "Surface Heat Flux" on the boundary nodes of a surface in ConductionFiniteDifference method. Same not in the terms of value but in the terms of meaning and how these both values are calculated in EP.

I am comparing heat flux from an experimental data (DSC) of a specimen with a virtual specimen in EP and in that error results from CTF algorithm looks better than CFD algorithm.

Has anybody experienced this before and if so what can be the reasons?

Edit- For more details-

I am simulating a conventional wall, subject to sinusoidal temperature excitation on the outer layer and constant temperature on the inner layer, with both CTF and CFD methods.

I have experimental data for comparison, and results from CTF simulation are much more consistent with experimental data then those with CFD. In particular, the heat flux at the indoor surface with CTF is (as expected) perfectly sinusoidal, while with CFD method it shows quite a large deviation from a perfect sinusoidal.

Thanks

 5 retagged __AmirRoth__ 4388 ●5 ●16 http://bleedinggreenna...

### Heat Flux at the surface nodes, CTF vs CFD method

Hi All,

First of all, can we consider "Face Conduction Heat Transfer Rate per Area" on a surface face(inside/outside) in ConductionTransferFunction method same as "Surface Heat Flux" on the boundary nodes of a surface in ConductionFiniteDifference method. Same not in the terms of value but in the terms of meaning and how these both values are calculated in EP.

I am comparing heat flux from an experimental data (DSC) of a specimen with a virtual specimen in EP and in that error results from CTF algorithm looks better than CFD algorithm.

Has anybody experienced this before and if so what can be the reasons?

Edit- For more details-

I am simulating a conventional wall, subject to sinusoidal temperature excitation on the outer layer and constant temperature on the inner layer, with both CTF and CFD methods.

I have experimental data for comparison, and results from CTF simulation are much more consistent with experimental data then those with CFD. In particular, the heat flux at the indoor surface with CTF is (as expected) perfectly sinusoidal, while with CFD method it shows quite a large deviation from a perfect sinusoidal.

Thanks