View Issue Details
ID | Project | Category | View Status | Date Submitted | Last Update |
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0001289 | OpenFOAM | Bug | public | 2014-05-12 13:29 | 2020-11-26 21:50 |
Reporter | chriss85 | Assigned To | henry | ||
Priority | normal | Severity | feature | Reproducibility | always |
Status | closed | Resolution | suspended | ||
Summary | 0001289: Limited validity range for multi-band fvDOM model | ||||
Description | The fvDOM model uses a blackBodyEmission class, which contains some pre-calculated values in a table for evaluating the integral over the planck function efficiently. However, the spectral range of this table is limited and doesn't cover some physically relevant ranges that can be appear (namely, in plasmas with temperatures between 2.000 - 50.000 K). In other works I've seen radiation being modelled between 30 nm and 4.5µm. The table provides values for ranges of lambda*T*1e6 between 1000 and 50000. In plasma applications values between 3e-8*2000*1e6=60 and 4,5e-6*50000*1e6=225000 can appear, for which this table is not sufficient on both sides (though the longer wavelengths contain not so much energy). Instead, I propose to calculate these values on startup instead of using a predefined table. This way, they could directly be calculated, considering the used spectral range and a user-specified temperature range for generating reasonable sampling points in the table. It should not take too much time to evaluate the integrals I think. I have another, slightly off-topic question: What exactly are the iEhrrCoeffs_ in the wideBandTabularAbsorptionEmission model? The comment says: //- Proportion of the heat released rate emitted I'm trying to implement a multi-band P1 model, and I don't see this coefficient appearing anywhere in my literature. Is it only relevant for fvDOM? | ||||
Tags | No tags attached. | ||||
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Alternatively, the user could provide a temperature-dependent table for each band containing the evaluated integrals. It would be nice to provide a script/program with OpenFOAM to calculate these tables then. I will probably use this approach myself until a bigger range is officially supported. |
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> Instead, I propose to calculate these values on startup instead of using a predefined table. Can you provide an implementation? |
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Pending funding or contribution. |
Date Modified | Username | Field | Change |
---|---|---|---|
2014-05-12 13:29 | chriss85 | New Issue | |
2014-05-12 13:33 | chriss85 | Note Added: 0003053 | |
2020-11-23 12:22 | henry | Note Added: 0011739 | |
2020-11-26 21:50 | henry | Assigned To | => henry |
2020-11-26 21:50 | henry | Status | new => closed |
2020-11-26 21:50 | henry | Resolution | open => suspended |
2020-11-26 21:50 | henry | Note Added: 0011773 |