Incorrect local variable scope in CalcInteriorSolarDistribution

[xuanluo113]

A potential bug in solar calculations in CalcInteriorSolarDistribution.

The reporting at the end of the function starts a new surface loop, but the WinTransBmBmSolar, WinTransBmDifSolar, TBmBm + TBmDif are not re-calculated. The value, WinTransBmBmSolar, WinTransBmBmSolar, and TBmBm + TBmDif used in the reporting loop are always the last calculated value for the last surface in the previous loop.

Defect file: testfiles/PurchAirWindowBlind_BlockBeamSolar.idf

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[mjwitte]

@xuanluo113 If I am following this correctly, this only impacts the following output variables. It does not affect the actual heat balance of the zone.

Window Transmitted Beam-to-Beam Solar
Window Transmitted Beam-to-Diffuse Solar
Window Transmitted Beam-to-Beam Solar Energy
Window Transmitted Beam-to-Diffuse Solar Energy

And these variables have been wrong since they were first added in 2009/2010.

[xuanluo113]

@mjwitte I agree.

1. The only reportable variables affected are:

• Surface Window Transmitted Beam To Beam Solar Radiation Rate
• Surface Window Transmitted Beam To Diffuse Solar Radiation Rate
• Surface Window Transmitted Beam To Beam Solar Radiation Energy
• Surface Window Transmitted Beam To Diffuse Solar Radiation Energy

This may only affect the result of PurchAirWindowBlind_BlockBeamSolar.idf that currently reports those. However, there is only one window per zone in this model, so using calculations of the last (and only) window in the reporting loop does not affect anything, coincidentally.

2. The other affected variable SurfWinDirSolTransAtIncAngle(SurfNum)// For TDD:DIFFUSER this is the TDD transmittance are not actually used anywhere, since the transmittance for the diffuser surface should be calculated as windows. My understanding is the variable declaration and calculation could be deleted. Would you mind confirming this by taking another look?

The fixes in PR #8358 show no diff.