These tasks can be used to prepare an aeroelasticity simulation with TRACE, e.g. for mapping an eigenmode from a structural mechanics computation into the CFD grid, modifying the properties of such eigenmodes in the cgns file, or computing a grind deformation corresponding to an eigenmode.

modify

Set (add or modify) modal properties of a structural mode which is present in the CGNS file (e.g. created by the mapping task).

Usage: --modify --cgnsFile <filename> --modename <name> [optionalOption] [argument]

Mandatory sub-options:

\( \)

long option	short option	arguments	description
`--cgnsFile`	`-cgns`	filename	CGNS file for input and output
`--modename`	`-mn`	name	specify the name of the mode to be modified

Optional sub-options:

\( \)

long option	short option	arguments	description
`--eigenmodeStatus`	`-ems`	'active' or 'inactive'	specifies status of the eigenmode
`--frequency`	`-f`	number	frequency [Hz]
	`-ibpa`	number	inter-blade phase angle [degree]
`--modalMass`	`-mm`	number	modal mass [kgm^2]
`--replaceHarmonicSet`		two numbers	specifies the harmonic set (identified by frequency and ibpa) for which modal properties are replaced or created by the modified values
`--modalMotionMethod`	`-mmm`	e.g. 'ModalFSI' or 'Harmonic'	motion method for an eigenmode

Example: --modify --cgnsFile TRACE.cgns --modename mode001 -f 1000 -ibpa 90

Precondition: The specified mode has to be present in the CGNS file.

Note: This task is executed on a single process.

Since: 6.7

initialCondition

Set the modal initial conditions of a structural mode which is present in the CGNS file (e.g. created by the mapping task). If a complex mode was mapped then the complex part is treated as a separate real eigenmode. In this case initial conditions for the two modes can be set with two arguments (see example, second line).

Usage: --initialCondition/-icon --cgnsFile <filename> --modename <name> [optionalOption] [argument]

Mandatory sub-options:

\( \)

long option	short option	arguments	description
`--cgnsFile`	`-cgns`	filename	CGNS file for input and output
`--modename`	`-mn`	name	specify the name of the mode to be modified

Optional sub-options:

\( \)

long option	short option	arguments	description
`--modalDisplacement`	`-mdis`	realPart [imagPart]	initial modal displacement
`--modalVelocity`	`-mvel`	realPart [imagPart]	initial modal velocity

Example: --initialCondition --cgnsFile TRACE.cgns --modename mode001 -mdis 0.0 -mvel 1.0

--initialCondition --cgnsFile TRACE.cgns --modename mode001 -mdis 0.0 1.0 -mvel 1.0 0.0

Precondition: The specified mode has to be present in the CGNS file.

Note: This task is executed on a single process.

Since: 9.2

removeAllEigenmodes

Remove all surface displacements and deformations from CGNS file.

Usage: --removeAllEigenmodes/-rae -cgns <filename> [optionalOption]

Mandatory sub-options:

\( \)

long option	short option	arguments	description
`--cgnsFile`	`-cgns`	filename	CGNS file for input and output

Optional sub-options:

\( \)

long option	short option	arguments	description
`--removeHarmonicSet`			specifies that along with the deformation the respective harmonic set is deleted

Example: --removeAllEigenmodes -cgns TRACE.cgns --removeHarmonicSet

Note: This task is executed on a single process.

Since: 6.7

removeEigenmode

Remove specified eigenmode from CGNS file (displacements and deformations).

Usage: --removeEigenmode/-rem -cgns <filename> --modename <name> [optionalOption]

Mandatory sub-options:

\( \)

long option	short option	arguments	description
`--cgnsFile`	`-cgns`	filename	CGNS file for input and output
`--modename`	`-mn`	mode name	name of the mode to be removed

Optional sub-options:

\( \)

long option	short option	arguments	description
`--removeHarmonicSet`			specifies that along with the deformation the respective harmonic set is deleted

Example: --removeEigenmode -cgns TRACE.cgns -mn mode001

Note: This task is executed on a single process.

Since: 7.0

deactivateAllEigenmodes

set mode status of all modes to 'inactive'

Usage: --deactivateAllEigenmodes/-dae -cgns <filename>

Mandatory sub-options:

\( \)

long option	short option	arguments	description
`--cgnsFile`	`-cgns`	filename	CGNS file for input and output

Note: This task is executed on a single process.

Since: 7.3

deleteFacesForFreeBoundaryCondition

Delete the face selection made by the task –selectFacesForFreeBoundaryCondition from CGNS file.

Usage: --deleteFacesForFreeBoundaryCondition/-dffb -cgns <CGNSFile>

Mandatory sub-options:

\( \)

long option	short option	arguments	description
`--cgnsFile`	`-cgns`	filename	CGNS file for input

Example: -cgns TRACE.cgns -dffb

Since: 9.0

fileInfo

Show the modal information stored in an eigenmode file (Patran or CalculiX results).

Usage: --fileInfo/-fi --eigenmodeFile <eigenmodeFile> --filetype <RPT/FRD>

Mandatory sub-options:

\( \)

long option	short option	arguments	description
`--eigenmodeFile`	`-emf`	filename	eigenmode file
`--filetype`	`-ft`	<RPT/FRD>	eigenmode file type

Example: -fi -emf eigenmodefile.frd -ft FRD

Since: 9.0

mapping

The ''mapping'' task can be used for two different purposes. One is to compute artificial mode shapes (rigid body motion comparable to torsion or bending) and store them in the CGNS file as displacements. The usual is to read eigenmodes, i.e. modal displacements, from FE-solver output files and map them on the CGNS geometry. The algorithms used in this process are described in the theory section Mapping Algorithm.

The modal displacements to be stored in the CGNS file have to be of one of the following formats:

Patran (file type option RPT and specify the element definition file with –elementfile)
CalculiX results (file type: FRD)
Tecplot (file type: TEC) (Only files consisting of a single zone are supported yet.)

Only surface data, i.e. displacements on a 2D unstructured mesh, is supported. Please make sure you wrote out only surfaces which align to the designated CGNS surfaces, i.e. panels and panel families, in the FE-postprocessing.

Usage: Mapping of eigenmode file:
--mapping/-m -cgns <filename> --eigenmodeFile <filename> --filetype <FRD|RPT|TEC> --modename <name> --panelfamily <names> [optionalOptions]

Generation of artificial modes:
--mapping/-m -cgns <filename> --bending/--distortion/--torsion <arguments> [optionalOptions]

Mandatory sub-options (for mapping of an eigenmode file):

\( \)

long option	short option	arguments	description
`--cgnsFile`	`-cgns`	filename	CGNS file for input and output (containing the geometry to which the eigenmode is mapped)
`--eigenmodeFile`	`-emf`	filename	file containing modal displacements
`--filetype`	`-ft`	type	define modal displacements file format as Patran [RPT], Calculix [FRD] or native Tecplot [TEC]
`--modename`	`-mn`	name	name under which the displacements for the given mode are stored in the cgns file
`--panelfamily`	`-pf`	(list of) name(s)	name(s) of one or more panel families to map the specified modal displacements on

Sub-options for artificial modes:

Exactly one of the following options has to be specified to define an artificial mode.

long option	arguments	description
`--bending`	four numbers (amplitude, vector)	compute and store an artificial bending mode with the given amplitude (in m) and translation vector
`--distortion`	nine numbers (three vectors)	store artificial distortion of blades (bump at [c] of width [w] into direction [d]), given as [dx dy dz cx cy cz wx wy wz]
`--torsion`	seven numbers (amplitude, vector, vector)	compute and store an artificial torsion mode with the given amplitude (in degree), base vector, and rotation vector
`--nozzle`	four numbers	compute and store an artificial mode representing a nozzle with the given parameters: maximum displacement (rotational: r, translational: z)and the axial coordinates of the start position, maximum displacement and the end position (in m)

Optional sub-options:

\( \)

long option	short option	arguments	description
`--addMode`	`-add`		add mode to existing modal displacements
`--amplify`	`-amp`	factor	amplify (i.e. scale-up) the modal displacements and depending data
`--conjugate`			specify the read eigenmodes as conjugate complex pairs
`--eigenmode`	`-em`	number	identifier for modal displacements to be mapped, results from the eigenmode file (only for frd and rpt files, use '`--fileinfo'` to determine)
`--elementFile`	`-edf`	file name	element definition file needed in addition to the Patran file
`--flip`		axes	rotate CSM geometry by 180 degrees around the specified axes, given as [X Y Z] or [1 2 3]
`--flipSurfaceNormals`			turn over surface normal vectors of the CSM grid, i.e. invert ordering of the nodes within the FE
`--keepFixed`	`-kf`	(list of) name(s)	name(s) of one or more panel containers where the mapping result is set to zero
`--mirror`		axes	inverse FE-coordinates of the specified axes, given as [X Y Z] or [1 2 3]
`--noAlign`			prevent the automatic alignment of the principal axes (i.e. leave them unsorted)
`--noRotation`			prevent the rotation of the CSM geometry in order to fit to the specified panel families
`--noShift`			prevent the automatic shifting of the CSM geometry in order to reconcile the center of areas of CSM geometry and specified panel family
`--oldMappingAlgorithm`	`-oma`		use the former implementation of NN-search and IDW for the 'MAPPING'
`--phaseshiftangle`	`-psa`	angle	perform a phase shift [degree] on the read eigenmode
`--readInterpolationMatrix`	`-rim`	format string	read interpolation matrix for mapping from file, format string for file name has to be given as argument
`--readTransformationMatrix`	`-rtm`	file name	read transformation matrix and centers of area of CSM and CFD geometry from file
`--simpleNearestNeighborSearch`			search the nearest neighbor independent of the surface normal directions
`--unitLength`	`-ul`	unit	specify the unit of length for the CSM geometry as either [m] or [mm] (default)
`--unitMass`	`-um`	unit	specify the unit of mass for the CSM geometry as either [kg] or [t] (default)
`--verbose`	`-v`		show details of what is being done
`--writeCSM`	`-wCSM`	[path]	write Tecplot files with the read and transformed CSM geometry and the CFD panel families containing the mapped surface displacements; to redirect the output specify a path as argument
`--writeInterpolationMatrix`	`-wim`	[format string]	write interpolation matrix from mapping to file (one file per block, format string for file name can be given optionally)
`--writeTransformationMatrix`	`-wtm`	file name	write transformation matrix and centers of area of CSM and CFD geometry to file
`--zeroDisplacementAtLargeDistance`	-zdad	distance panelFamily1 panelFamily2	sets modal displacements to zero if the distance of a mesh node to the next FEM face is too large. Usage: -zdad <distance> <panelFamily1> <panelFamily2> ...
`--inputJSONFile`	`-js`	filename	JSON file containing several modes to be mapped from an FRD file as a JSON array. Each array item contains dictionary items corresponding to the mapping options ('modename' (string), 'eigenmode' (number), 'analysisFrequency' (number), 'modalMotionMethod' (string), 'eigenmodeStatus' (string))

Artificial mode 'Nozzle'

For this artificial mode four parameters have to be specified (in m):

\({\delta}_{center}\) : maximum displacement (rotational: r, translational: z) at the center position
\(x_{start}\) : axial coordinate of the start position (in m)
\(x_{center}\) : axial coordinate of the maximum displacement (in m)
\(x_{end}\) : axial coordinate of the end position (in m)

The following functions are used to define the outline of the nozzle. For \(x < x_{Center}\)

\begin{equation} {\delta} = +/-\frac{1}{2} {\delta}_{center} \left(1 + \cos\left(\pi * \frac{x_{center} - x}{x_{center} - x_{start}}\right)\right) \end{equation}

with \(x > x_{Center}\)

\begin{equation} {\delta} = +/- \frac{1}{2} {\delta}_{center} \left(1 + \cos\left(\pi * \frac{x - x_{center}}{x_{end} - x_{center}}\right)\right)\\ \end{equation}

The sign of the displacement depends on the normal vector of the related panel family. It is positive if the normal vector points in positive radial direction.

Example

Mapping of eigenmode from Tecplot file:

--mapping -cgns ROTATIONAL.cgns -emf row01Hub_Wall.cplx.dat -ft TEC -uL m -mn ModeXXX -pf row01Hub_Wall row01Hub_cooling -amp 0.004 --flipSurfaceNormals -wCSM ../output

Mapping of eigenmode from frd file:

--mapping -cgns TRACE.cgns -emf twoMode_DISP.frd -ft FRD -em 2 -mn mode000 -pf row01Blade_Wall_ps row01Blade_Wall_ss

Mapping of eigenmode from rpt file:

--mapping -cgns TRACE.aePrePro.cgns -pf R4_BLADE -emf Turbine_Blade_Freestanding_modes1_2_w_tip.rpt -ft RPT -em 1 -edf Turbine_Blade_Freestanding_elements.dat -mn Mode -amp 1.e-1

Mapping with phase shift angle:

--mapping -cgns clock.cgns -pf 1oclock -emf midnight.dat -ft TEC -ul m -mn wavingClock -psa 30 -amp 2.

Artificial bending mode:

--mapping -cgns TRACE.linear.cgns --bending 0.0001 1 1 0 -pf SOLID_BLADE -mn mode000 -lb BALANCE

Artificial torsion mode:

--mapping -cgns TRACE.cgns --modename torsion --panelFamily blade0 -psa 45. --torsion 0.1 0.334456 0.448989 15.9025 0. 0.448989 15.9025

Artificial nozzle mode:

--mapping -cgns TRACE.cgns --modename nozzle --panelFamily row01Hub_Wall row01Tip_Wall --nozzle -0.005 0.8 0.815 0.85

Note: You can specify the parameters and panel families for only one eigenmode - modal displacement at once. If a mode with the specified mode name already exists, PREP will throw an error.; The default unit of length for the mode file input is [mm] and the default unit of mass is [t]. You can specify [m] as unit of length and/or [kg] as unit of mass by using commands listed above. Within the mapping, deformation or any postprocessing all units and measurements are conform to the SI base units.; This task can be executed in parallel.

Since: 6.7

deformation

Perform mesh deformation for given modal displacements.

To compute the deformed mesh, i.e. to distribute a single set of modal displacements per blade family over the 3D mesh, specify the combination of displacements, panel families and parameters via --modename name.

Usage: --deformation/-d --cgnsFile <filename> --modename <name> [optionalOptions]

Mandatory sub-options:

\( \)

long option	short option	arguments	description
`--cgnsFile`	`-cgns`	filename	CGNS file for input and output
`--modename`	`-mn`	name	name of eigenmode for which the deformation is performed

Optional sub-options:

\( \)

long option	short option	arguments	description
`--addHarmonicSet`			specifies that the deformation will be added as new harmonic set
`--deformationTolerance`	`-dt`	number	set tolerance value for the correction of the deformation result (default: global tolerance)
`--DirichletBoundaryConditions`	`-dbc`		use Dirichlet boundary conditions on all solid panels
`--freeBoundary`	`-fb`	name	specify a panel family where free boundary conditions are to be used
`--releaseEntryExit`	`-ree`		allow deformation at entry and exit panel in azimuthal direction
`--terminationCriterion`	`-tc`		specify relative termination criterion for GMRES algorithm (default value is 1.e-5)
`--volumeWeightingExponent`	`-vwe`	number	specify exponent for weighting of inverse cell volume in mesh deformation between 0 (no volume weighting) and 1 (default), can be used if deformation with full weighting does not converge
`--writeDeformedGrid`	`-wdg`	file name(s)	Triggers output of the deformed grid. Specify an output file for the real part of the deformed grid and in case of a complex deformation a second for the imaginary part; existing files will be overwritten.
`--DirichletOnPeriodicBoundaries`	`-dpb`		use Dirichlet boundary conditions on all periodic boundaries for deformation

Example: --deformation -cgns TRACE.linear.cgns -mn BendingMode

writes deformations (2D and 3D) as flow solution into TRACE.linear.cgns, deformed grid is not written
--deformation -cgns ROTATIONAL.cgns -mn ModeXXX --releaseEntryExit --writeDeformedGrid ../output/ROTATIONAL.deformed.real.cgns ../output/ROTATIONAL.deformed.imag.cgns

writes real and imaginary parts of deformed grid into specified files, the mesh at inlet and outlet boundaries may be deformed

Precondition: Surface displacements have to be present in the CGNS file, they can be written using the mapping task.

Note: This task can be executed in parallel.

Since: 6.7

selectFacesForFreeBoundaryCondition

Select faces from panel families which will not receive a mapped surface deformation but are marked for a "free" (Neumann) boundary condition for the mesh deformation. The faces are selected by providing a point list file (-plf). If the distance between a face and the nearest point from the provided point list is smaller than a predefined tolerance (-r), the face is selected for a Neumann boundary condition. The panel families for which this procedure should be considered (-pf) and the point list file type (-ft) must also be specified.

Usage: --selectFacesForFreeBoundaryCondition/-sffb -cgns <CGNSFile> -ft <RPT/FRD/TEC> -pf <panelFamilies> -plf <pointListFile> -r <radius>

Mandatory sub-options:

\( \)

long option	short option	arguments	description
`--cgnsFile`	`-cgns`	filename	CGNS file for input
`--filetype`	`-ft`	RPT/FRD/TEC	point list file format
`--panelfamily`	`-pf`	all relevant panelFamilies	all panel families which should be considered
`--pointListFile`	`-plf`	the point list file	file which contains the point list
`--radius`	`-r`	a number	the tolerance value for the distance between points and faces
`--readTransformationMatrix` or --noTransformationMatrix	`-rtm` or -ntm		reads transformation matrix and CSM and CFD geometry centers of area from file or use none (.ntm)

Optional sub-options:

\( \)

long option	short option	arguments	description
`--unitLength`	`-ul`	m/mm	specify the unit of length for the CSM geometry as either [m] or [mm] (default)
`--writeCSM`	`-wCSM`		writes Tecplot files with the read and transformed CSM geometry and the CFD panel families containing the mapped surface displacements; to redirect the output specify a path as argument

Example: -cgns TRACE.cgns -sffb -plf Line.dat -ft TEC -r 0.001 -pf row01Tip_Wall -rtm transformation.dat -ul m

Since: 9.0