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radiation setting, how?

Hi,

In the solar radiation model mentioned that:

specular transmissivity + diffuse transmissivity + specular reflectivity + diffuse reflectivity + absorptivity = 1

The questions are:

1) In Acuconsole, absorptivity does not need to specify. So, is it means that it is automatically generated based on above equation?

E.g: 0.5+0+0.2+0+absorptivity=1

Is it means that absorptivity value automatically = 0.3??

2) Is it emissivity value must be equal to absorptivity value??

Thanks

Sorry for my english..

AcuSolve

English

1. Yes absorptivity is the rest of the equation, as you mentioned

2. AcuSolve takes absoprtivity = emissivity and hence you once specify emissivity

1. Yes absorptivity is the rest of the equation, as you mentioned

2. AcuSolve takes absoprtivity = emissivity and hence you once specify emissivity

Regarding question 2, if we setup specular transmissivity = 0.35, specular reflectivity = 0.05 and emissivity = 0.6

what is value of absorptivity?

Thanks

Regarding question 2, if we setup specular transmissivity = 0.35, specular reflectivity = 0.05 and emissivity = 0.6

what is value of absorptivity?

Thanks

For solar radiation model, absorptivity would be calculated from the rest of the equation

i.e. 1- Transsivities - reflectivities (page 63 of Command reference manual)

For enclosure radiation mode, absorptivity would be equal to emissivity. (Kirchhoff Law and gray surface assumption, Pg 56 CRM)