IBM Release 1.93 manual Object Group, Block, Fan

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Type PEC Type black

Perfect conductor. All fields inside a PEC are zero. Sometimes useful for saving CPU cycles in regions where the fields are known to be zero, e.g. deep inside metal objects.

Parameters: none

3.1.5. OBJECT Group

Like all dimensions in POEMS, object dimensions are measured from edge to edge, as you would measure with calipers. All dimensions are correctly rounded to the nearest multiple of basicstep in the subdomain in which they occur. A cell is included if its centre lies inside the specified region. This can lead to steps at boundaries between subdomains with different basicstep values, due to differences in rounding.

When an object’s midline is specified in terms of a curve, e.g. FAN, GRATING, CURVE, and 3DCURVE, the end points of the curve are taken to lie at the centre of the outermost plane of blocks on each end. This makes sure that if the local object axis is highly inclined, the outermost blocks don’t disappear due to their centres falling outside the region, as they would if the endpoint were taken to lie in the outer face. Sufficiently inclined objects may still become discontinuous.

BLOCK	Adds a rectangular prism (like a shoe box) of material matname,
	covering the region xlo ≤ x ≤ xhi, ylo ≤ y ≤ yhi, zlo ≤ z ≤ zhi. Like
	everything else in POEMS, these dimensions will be rounded to the
	nearest cell boundaries.
	Parameters: matname xlo xhi ylo yhi zlo zhi
	Example:
	block matname = AirPML xlo=0 xhi=8*dx ylo = 0 yhi=ymax ,
	zlo=0 zhi=zmax

FAN	Adds a fan shaped object such as a dielectric waveguide horn or
	taper. A fan is specified by a choice of curve and rectangular end
	faces 1 and 2, defined by their diagonal points ((xlo1,ylo1,zlo1),
	(xhi1,yhi1,zhi1)) and ((xlo2,ylo2,zlo2), (xhi2,yhi2,zhi2)). These must be
	parallel and lie in a coordinate plane. Intervening planes are
	defined by the choice of taper and the taper parameter, which is a
	scale factor for the domain of the curve—increasing the parameter
	causes the taper to be sharper, and decreasing it makes the taper
	more gradual. Allowed tapers are LINEAR, EXPONENTIAL, and
	ERF. Exponential tapers are useful for converting guided waves to
	free space, and ERF tapers are useful for converting between
	different-sized waveguides without strong back reflections from
	either end.

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Contents IBM T. J. Watson Research Center Yorktown Heights, NY Page IBM T. J. Watson Research Center Yorktown Heights, NY Using Poems HOW Poems WorksChapter Introduction MotivationPhilosophy Structure OptimizationPage Poems system organization Front-End Script poems.cmd Program OrganizationScript Operation Fdtd Engine FIDO/TEMPEST Postprocessor EmpostVisualization System VIS5D Cluster ControlParallel Processing Poems Command-Line Options Command ReferenceGlobal Group Function FreqLambda HostsWhich means that the host’s predefined hostname is not used MacdefMacro PrintSET RandomseedSimulator Verbose World GroupTitle BoundaryXrange Yrange Material GroupBasicstep DefineParameters epsReal epsImag muReal muImag Block Object GroupFAN Hollowbox GratingTiledplane 3DCURVE CurveCylinder Source Group Command Group Output GroupCAD Postprocess GroupField WebpageFlux FarfieldIntegral List ModematchMovie MOVIE3DDissipation SliceVariables Optimize GroupGuess Store LimitPenalty Merit Parameters Schedule GroupRange Computational Domain SymmetryObjects Perfectly-Matched Layers MaterialsPlane Waves Page Beam Sources Optimization Merit FunctionsPhase uniformity across a plane Worked Example Optimizing a V Antenna 10 Optimized V antenna refractivePage Worked Example Glass Ridge Waveguide to Free Space Coupler Worked Example Doped Silica Waveguide ModePredefined Constants Reserved Names ConfinePredefined Mathematical Functions Arithmetic OperatorsAcos Logical OperatorsABS AcoshCOS ATAN2Ceil ElintkMAX Integral20. LN MINRound RandomROOT1D SignMaterial Parameter Functions Analytical Pupil FunctionsFlattop Startup and Steady State Tempest and General Fdtd InformationTime step Page Appendix A. V-Antenna Optimization Run Poems Input DIPOLE2I.PAR END Material END World Subdomain ALL END ObjectEND Source END CommandEND Output END Optimize Phaseex END Postprocess AmplexPage Page Page END Tempest Input File DIPOLE2I.PAR.IN Written by Phil Hobbs Pages of pointsource statements omitted DIPOLE2IEXI Postprocessor orders DIPOLE2I.ORDERSALL DIPOLE2IEXQDIPOLE2IEZI DIPOLE2IEYIDIPOLE2IEYQ DIPOLE2IEZQArray Amplex MiddlefluxPOSTPROC.1.NAME POSTPROC.1.PARMSTRINGPOSTPROC.2.PARMSTRING DIPOLE2IPHASEEXArray FF2Array Poyntingz DIPOLE2IPXPOSTPROC.6.NAME DIPOLE2IPZPOSTPROC.11.NAME POSTPROC.9.PARMSTRINGPOSTPROC.10.PARMSTRING Slice IndexnDIPOLE2IPZXY0.BMP Slice PoyntingzPOSTPROC.13.COMPARISONDOMAIN POSTPROC.14.NAMEPOSTPROC.17.NAME POSTPROC.16.COMPARISONDOMAINDIPOLE2IPXZX0.BMP Slice AmplexPOSTPROC.20.COMPARISONDOMAIN DIPOLE2IPHASEEXXY0.BMPDIPOLE2IPHASEEXZX0.BMP DIPOLE2IDISSZX0.BMPPOSTPROC.24.COMPARISONDOMAIN DIPOLE2IEXQZX0.BMPRun Results DIPOLE2I.SIMPLEX Page Page Page Page Page Fdtd and Tempest Tempest patchesAdvice common to all or most Fdtd programs Tempest limitationsWindow System Configuration Sample X11 ConfigurationRelease Notes Running Vis5DWish list Beta Release Limitations Page Page Emdenormal Emunderflow IndexMatlab Maxordersources 81 Maxpointsources