Solver Parameters dialog box — Radiation Parameters

View Factor Calculation
View Factor Adjustment	Specifies a method to eliminate the residual view factor.SelfCreates a view factor to the element.NormalizedAdjusts the computed view factors iteratively to bring the view factor sum for each element as close to 1.0 as possible.Residual to Radiative EnvironmentCreates a view factor to the implicit radiative environment temperature.
Small View Factors	Specifies the method for disposing of the smallest view factors.Dispose ofDismisses small view factors whose value is less than the value you specify in the View Factors less than box.Dispose up toDismisses small view factors whose sum is less than the value you specify in the Sum of Disposed View Factors less than box.
Use Radiation Patches	Merges adjacent elements temporarily, for the purpose of calculating radiative exchange.
On Screen Rendering	Accelerates view factor calculation when you use the Hemicube Rendering method.When running in parallel, each computer must have a graphics card, and each computer can use only one processor, even if it has more.If on screen rendering is impossible or impractical, clear this check box.
Ignore Specular and Transparent Effects for Radiation Request Calculations	Ignores the calculation of specular and transparent effects for black body view factors in enclosures. If these effects are significant in your model, clear this check box.See Understanding enclosures for more information.
Allow all Elements to Shadow for Solar Heating Requests	Includes all elements with appropriate thermal properties in shadowing checks for solar heating requests. If you want to include only elements selected in solar heating requests in shadowing checks, clear this check box.
Use Segregated Radiation Solver	Uses the segregated radiation solver which separates the calculation of radiative and non-radiative terms into matrix equations. If you want to solve the model using a single matrix equation that contains both radiative and non-radiative conductances, clear this check box.
Element Subdivision	Specifies the granularity of the element subdivision for computing shadowed view factors. A higher subdivision level will yield more accurate radiative conductances at the cost of additional computation time. Select one of six levels of granularity numbered 0 to 5.
Number of Axisymmetric Segments	Sets the number of radial sections created in axisymmetric models. In axisymmetric solutions, 2D and 1D elements are revolved around the axisymmetric axis for a complete revolution. This creates temporary 3D models from which view factors are computed. The greater the number of segments, the more accurate the results, but the processing time is longer.
Beam Options
Close End of Beams	Models radiation from the free ends of beam elements.When no radiation is emitted from the free ends, clear this check box to model 1D beam elements as hollow cylinders with open ends.
Spectral Bands
Bands	Specifies the method for calculating the spectral bands used in the calculation of radiative exchange in the model.Solar and IRComputes only these two bands in the calculation of radiative exchange.This setting is adequate for most applications.Based on Temperature RangeComputes two or more bands defined by minimum and maximum temperatures that you specify in the Minimum Black Body Temperature and Maximum Black Body Temperature boxes. These values are the anticipated minimum and maximum radiating temperatures in the model. They set the lower and higher wavelength limits for the spectral band discretization. You specify the number of spectral bands in the Total Number of Bands box.Based on Key TemperaturesComputes two or more bands delimited by the wavelengths at the peak of the black body spectrum for each representative temperature that you enter in the Black Body Temperature Table in the specified units.Equal Power IntervalsComputes two or more bands such that a black body radiation at the specified temperature will radiate equal power into each band. You specify a single characteristic black body temperature for the model in the Black Body Temperature box. You specify the number of spectral bands in the Total Number of Bands box.Wavelength RangeComputes two or more bands between minimum and maximum wavelengths that you specify in the Minimum Wavelength and Maximum Wavelength boxes. The minimum wavelength sets the upper limit of the lowest band of the modelThe maximum wavelength sets the lower limit of the highest band of the model.You specify the total number of spectral bands for this model in the Number of Bands in Range box.Specify WavelengthSpecifies wavelengths to demarcate the spectral bands that you enter in the Wavelength Breakpoint Table in the specified units.The values that you enter in the Black Body Temperature Table or the Wavelength Breakpoint Table must be separated by commas or they must be entered on different lines. You can use the Cut , Copy , and Paste commands.
Spectral Model	Appears when Bands is set to any option except Solar and IR.Specifies how bands are used in the infrared (IR) and solar regions of the spectrum.Full Multi-bandsDefines the full band range for radiative heating calculation.One Band for IRUses only one band for the calculation of gray infrared heat transfer.
Solar to IR Transition Wavelength	Sets the transition wavelength that demarcates the transition between the infrared (IR) and solar spectra.The default value of 0.003 mm is the peak of the blackbody curve for a body radiating at 1000 K. At this value, the majority of the solar spectrum lies in the solar band, and a body with a temperature of less than 700 K radiates mostly in the IR band.
Solar Intensity versus Wavelength	Defines the solar intensity as a function of wavelength.You specify the solar intensity field that varies with wavelength in the Solar Intensity Table using the Specify Field options.Select Existing Field from List opens the Fields dialog box, where you can select a field. For more information, see Fields.Formula Constructor opens the Formula Field dialog box, where you can define a formula to construct a field. For more information, see Define a boundary condition using a formula field.Table Constructor opens the Table Field dialog box, where you can define tabular data to construct a field. For more information, see Define a boundary condition using a table field and Define a material property using a table field.Link Constructor opens the Linked Field dialog box, where you can construct a linked field from an existing spatial field. For more information, see Linked Field dialog box.Plot (XY) lets you plot the field as an XY graph. For more information, see Graph overview.Overlay(XY) lets you overlay a plot on an existing plot. You can overlay up to 50 plots. For more information, see Overlay plots.You specify a correction factor which the software applies to the variable values of the solar intensity in the Scale Factor box.

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Solver Parameters dialog box — Radiation Parameters, Simcenter 3D 2021.1 Series

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