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AcuSolve User-Defined Functions Manual
Customization of AcuSolve allowing you to customize certain capabilities of the solver.
Global Routines
These routines are accessible by all user functions, and by external output codes.
udfGetGlobalHistsPrev2()
Get the previous global history variables.

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AcuSolve Training Manual
Introduction of background knowledge regarding flow physics and CFD as well as detailed information about the use of AcuSolve and what specific options do.
AcuSolve Validation Manual
Collection of AcuSolve simulation cases for which results are compared against analytical or experimental results to demonstrate the accuracy of AcuSolve results.
AcuSolve Command Reference Manual
AcuSolve command descriptions and corresponding examples.
AcuSolve Programs Reference Manual
AcuSolve utility programs covering preparatory and post-processing as well as user-defined functions and utility scripts.
AcuSolve User-Defined Functions Manual
Customization of AcuSolve allowing you to customize certain capabilities of the solver.
- Input File
  To access a user-defined function in AcuSolve, you must reference it in the input file.
- Function Format
  A user-defined function has the following form (in C).
- Compile, Link and Run
  In order for the solver to access the user-defined functions, the functions must be compiled and linked into a shared library. The script acuMakeLib (for Linux) and acuMakeDll (for Windows) may be used for this purpose.
- Support Routines
  Within a user-defined function or an external output code data may be accessed through support routines. These routines provide flexibility, longevity, efficiency and the ability to check for run-time errors.
- Basic Routines
  These routines are accessible by all user functions, and by external output codes.
- Client/Server Routines
  These routines are accessible only by multiplier function and mesh motion user functions.
- Global Routines
  These routines are accessible by all user functions, and by external output codes.
  - udfGetTimeStep()
    Return the current time step.
  - udfGetTime()
    Return the time of the current time step.
  - udfGetTimeAlpha()
    Return the time at the alpha point of the generalized-alpha time marching algorithm.
  - udfGetTimeInc()
    Return the current time increment.
  - udfGetResidualNorm()
    Return the current residual norm of requested equation. This value forms the numerator of the residual ratio for the given equation.
  - udfGetResidualRatio()
    Return the current residual ratio of the requested equation.
  - udfGetSolutionNorm()
    Return the current solution norm of requested equation. This value forms the numerator of the solution ratio for the given equation.
  - udfGetSolutionRatio()
    Return the current solution ratio of the requested equation.
  - udfHasFlow()
    Does this problem contain flow equations?
  - udfHasTemp()
    Does this problem contain a temperature equation?
  - udfHasSpec()
    Does this problem contain species equations?
  - udfHasTurb()
    Does this problem contain a turbulence equation?
  - udfHasAle()
    Does this problem have mesh movement?
  - udfGetNumSpecs()
    Number of species transport equations in the problem.
  - udfGetActSpecId()
    The identification number of the current species being solved.
  - udfGetOsiData()
    Return data from an integrated surface output set.
  - udfGetOssData()
    Return the nodal statistics (minimum, maximum and standard deviation) from a surface output set.
  - udfGetOriData()
    Return data from an integrated radiation surface output set.
  - udfGetOeiData()
    Return data from an integrated element output set.
  - udfGetFanData()
    Return data of a fan component.
  - udfGetHecData()
    Return data of a heat exchanger component.
  - udfGetEDEMData()
    Return the data for a variable.
  - udfGetMfData()
    Return data of a multiplier function.
  - udfSetMfData()
    Set the value of a multiplier function.
  - udfGetFbdData()
    Return data from a flexible body set.
  - udfGetMmoRgdData()
    Return data from a rigid body mesh motion.
  - udfGetMmoRgdJac()
    Return storage for rigid body external force or moment derivatives with respect to displacement or rotation.
  - udfHasUgd()
    Has this user global data been set?
  - udfCheckUgd()
    Check the existence of a user global data.
  - udfSetUgdData()
    Set the value of a user global data.
  - udfGetUgdData()
    Return the value of a user global data.
  - udfGetGlobalVector()
    Return a user global vector.
  - udfBuildMmo()
    Build the mesh motion transformation matrix.
  - udfGetGlobalHistsCurr1()
    Get the current global history variables.
  - udfGetGlobalHistsPrev1()
    Get the previous global history variables.
  - udfGetGlobalHistsCurr2()
    Get the current global history variables.
  - udfGetGlobalHistsPrev2()
    Get the previous global history variables.
  - udfGetGlobalHistsCurr3()
    Get the current global history variables.
  - udfGetGlobalHistsPrev3()
    Get the previous global history variables.
  - udfGetNumSds()
    Return the number of subdomains.
  - udfGetSdId()
    Return the ID of the subdomain.
  - udfGetLastStepFlag()
    Is this the last time step?
  - udfMeanConv()
    Compute the mean and confidence of a signal.
- Element Routines
  These routines are accessible only by the Body Force, Material Model and Component Model user functions, and by external output codes.
- Element Boundary Condition Routines
  These support routines are accessible only by the Element Boundary Condition user functions, and by external output codes.
- Nodal Boundary Condition Routines
  These support routines are accessible only by the Nodal Boundary Condition user functions.
- Nodal Initial Condition Routines
  These support routines are accessible only by the Nodal Initial Condition user functions.
- Periodic Boundary Condition Routines
  These support routines are accessible only by the Periodic Boundary Condition user functions.
- Subdomain Routines
  These support routines are accessible only within external output codes.
AcuTrace Command Reference Manual
Commands of AcuTrace, a particle tracer that runs as a post-processor to or a co-processor with AcuSolve.
AcuTrace User-Defined Functions Manual
Instructions to define additional solution quantities of AcuTrace called user equations.
AcuReport Reference Manual
Instruction of the AcuReport tool, a standalone post-processor batch tool used to generate a report from an AcuSolve solution database.
AcuSolve Surface Processing

udfGetGlobalHistsPrev2()

Get the previous global history variables.

Syntax

vec = udfGetGlobalHistsPrev2( udfHd, nSize, id1, id2 ) ;

Type

AcuSolve User-Defined Function Global

Parameters

udfHd: The opaque handle (pointer) which was passed to the user function.
nSize (integer): Size of vector.
id1 (integer): index 1.
id2 (integer): index 2.

Return Value

vec (real): Pointer to the global vector

Description

This routine returns a pointer to (id1, id2)-th previous global history variables in size nSize vector. For example,

Real* vec ;
...
vec = udfGetGlobalHistsPrev2( udfHd, nSize, id1, id2 )

Errors

This routine expects a valid udfHd.