Theweighted-sum-of-gray-gases(WSGG)modeliswidelyusedinengineeringcomputationsof
radiativeheattransferduetoitsrelativesimplicity,robustnessandflexibility.Thispaper
presents thecomputationofradiativeheattransferina2Daxisymmetricchamberusingtwo
WSGGmodelstocomputeradiationinH2O andCO2 mixtures.Thefirstmodelconsidersafixed
ratiobetweenthemolarconcentrationsofH2O andCO2, whilethesecondallowsthesolution
for arbitraryratios.Thecorrelationsforboth modelsarebasedontheHITEMP2010database.
The testcaseconsiderstypicalconditionsfoundinturbulentmethaneflames,withsteep
variationsinthetemperaturefieldaswellasinthemolarconcentrationsoftheparticipating
species.ToassesstheaccuracyoftheWSGGmodel,theresultsarecomparedwithasolution
obtainedbyline-by-lineintegration(LBL)ofthespectrum.
conditions. Its use, however, is usually associated with a
reduction of the overall energetic performance of the
plant.
In order to balance, to some extent, the decrease in
performance of the plant, accurate design procedures
are needed. The relative sizing of each of the components
of the plant is crucial for cycle performance. For
this reason, the accurate prediction of heat transfer
characteristics in condensers and evaporators is
required. In this study R22 and R407C heat transfer
coefficients during condensation are evaluated by means
of an experimental vapour compression plant.
condensation are reported.