Appendix

Appendix 1 - Available User's Arguments

Available Starter User's Arguments

Table 1. Starter User’s Arguments – Material Law for Shells
Variable	Size	Type	Write/read	Definition
`IIN`	1	Integer	R	Input file unit (Starter input file)
`IOUT`	1	Integer	R	Output file unit (Starter output file)
`UPARAM`	`NUPARAM`	Float	W	User’s parameter
`MAXNUPARAM`	1	Integer	R	Maximum size of `UPARAM`
`NUPARAM`	1	Integer	W	Size of `UPARAM`
`NUVAR`	1	Integer	W	Number of user’s variables
`IFUNC`	`NFUNCT`	Integer	W	Function number array
`MAXNFUNC`	1	Integer	R	Maximum size of `IFUNC`
`NFUNCT`	1	Integer	W	Size of `IFUNC`
`PARMAT`	3	Float	W	(1) Stiffness modulus for interface (2) Young's modulus (for shell) (3) Poisson’s ratio (for shell)

Table 2. Starter User’s Arguments – Material Law for Bricks
Variable	Size	Type	Write/read	Definition
`IIN`	1	Integer	R	Input file unit (Starter input file)
`IOUT`	1	Integer	R	Output file unit (Starter output file)
`UPARAM`	`NUPARAM`	Float	W	User’s parameter
`MAXNUPARAM`	1	Integer	R	Maximum size of `UPARAM`
`NUPARAM`	1	Integer	W	Size of `UPARAM`
`NUVAR`	1	Integer	W	Number of user’s variables
`IFUNC`	`NFUNCT`	Integer	W	Function number array
`MAXNFUNC`	1	Integer	R	Maximum size of `IFUNC`
`NFUNCT`	1	Integer	W	Size of `IFUNC`
`STIFINT`	1	Integer	W	Stiffness modulus for interface

Table 3. Starter User’s Arguments – Spring Property
Variable	Size	Type	Write/read	Definition
`IIN`	1	Integer	R	Input file unit (Starter input file)
`IOUT`	1	Integer	R	Output file unit (Starter output file)
`NUVAR`	1	Integer	W	Number of user’s variables
`UVAR`	`NUVAR`* `NEL`	Float	R/W	User’s variable
`PARGEO`	*	Float	W	(1) Skew number (2) Stiffness for interface (3) Front wave option
`NEL`	1	Integer	R	Number of elements
`IPROP`	1	Integer	R	Property number
`IX`	3* `NEL`	Float	R	Spring connectivity
`XL`	`NEL`	Float	R	Element length
`MASS`	`NEL`	Float	W	Element mass
`XINER`	`NEL`	Float	W	Element inertia (spherical)
`STIFM`	`NEL`	Float	W	Element stiffness (time step)
`STIFR`	`NEL`	Float	W	Element rotation stiffness (time step)
`VISCM`	`NEL`	Float	W	Element viscosity (time step)
`VISCR`	`NEL`	Float	W	Element rotation viscosity (time step)

Table 4. Starter User’s Arguments – Solid Property
Variable	Size	Type	Write/read	Definition
`NEL`	1	Integer	R	Number of elements
`IIN`	1	Integer	R	Input file unit (Starter input file)
`IOUT`	1	Integer	R	Output file unit (Starter output file)
`NUVAR`	1	Integer	W	Number of user’s variables
`UVAR`	`NUVAR`* `NEL`	Float	R/W	User’s variable
`PARGEO`	*	Float	W	(1) Skew number (2) Stiffness for interface (3) Front wave option
`IPROP`	1	Integer	R	Property number
`IMAT`	1	Integer	R	Material number
`SOLID_ID`	`NEL`	Integer	R	Solid Element id t=0
`EINT`	`NEL`	Float	W	Total internal energy t=0
`VOL`	`NEL`	Float	R/W	Initial volume
`OFF`	`NEL`	Float	R/W	Delete flag
`RHO`	`NEL`	Float	R/W	Density
`SIG`	6*`NEL`	Float	R/W	Stress tensor
`XX1`	`NEL`	Float	R	X coordinate node 1
`YY1`	`NEL`	Float	R	Y coordinate node 1
`ZZ1`	`NEL`	Float	R	Z coordinate node 1
`XX2` . . `ZZ8`	`NEL`	Float	R	Same for node 2 to 8
`VX1`	`NEL`	Float	R	X velocity node 1
`VY1`	`NEL`	Float	R	Y velocity node 1
`VZ1`	`NEL`	Float	R	Z velocity node 1
`VRX1`	`NEL`	Float	R	X rotational velocity node 1
`VRY1`	`NEL`	Float	R	Y rotational velocity node 1
`VRZ1`	`NEL`	Float	R	Z rotational velocity node 1
`MAS1`	`NEL`	Float	W	Mass node 1
`MAS2` . . `MAS8`	`NEL`	Float	W	Same for node 2 to 8
`INN1`	`NEL`	Float	W	Inertia node 1
`INN2` . . `INN8`	`NEL`	Float	W	Same for node 2 to 8
`STIFM`	`NEL`	Float	W	Element stiffness (time step)
`STIFR`	`NEL`	Float	W	Element rotation stiffness (time step)
`VISCM`	`NEL`	Float	W	Element viscosity (time step)
`VISCR`	`NEL`	Float	W	Element rotation viscosity (time step)

Table 5. Starter User’s Arguments – Sensor
Variable	Size	Type	Write/read	Definition
`IIN`	1	Integer	R	Input file unit (Starter input file)
`IOUT`	1	Integer	R	Output file unit (Starter output file)

Available Engine User's Arguments

Table 6. Engine User’s Arguments – Material Law for Shells
Variable	Size	Type	Write/read	Definition
`NEL`	1	Integer	R	Number of elements
`UVAR`	`NUVAR`* `NEL`	Float	R/W	User’s variable
`UPARAM`	`NUPARAM`	Float	W	User’s parameter
`NUPARAM`	1	Integer	W	Size of `UPARAM`
`NUVAR`	1	Integer	W	Number of user’s variables
`NFUNCT`	1	Integer	W	Size of `IFUNC`
`IFUNC`	`NFUNCT`	Integer	W	Function number array
`NPF`	*	Integer	R	Function array
`NPT`	1	Integer	R	Number of layers or integration points
`IPT`	1	Integer	R	Layer or integration point number
`IFLAG`	*	Integer	R	Geometrical flags
`TF`	*	Float	R	Function array
`NGL`	`NEL`	Integer	R	Element number
`TIME`	1	Float	R	Current time
`TIMESTEP`	1	Float	R	Current time step
`RHO0`	`NEL`	Float	R	Initial density
`AREA`	`NEL`	Float	R	Area
`EINT`	`NEL`	Float	R	Total internal energy
`THKLY`	`NEL`	Float	R	Layer thickness
`EPSPXX`	`NEL`	Float	W	Strain rate XX
`DEPSXX`	`NEL`	Float	W	Strain increment XX
`EPSXX`	`NEL`	Float	W	Strain XX
`SIGOXX`	`NEL`	Float	W	Old elasto-plastic stress XX
`SIGNXX`	`NEL`	Float	W	New elasto-plastic stress XX
`SIGVXX`	`NEL`	Float	W	Viscous stress XX
`SOUNDSP`	`NEL`	Float	W	Sound speed (time step)
`VISCMAX`	`NEL`	Float	W	Max damping modulus (time step)
`THK`	`NEL`	Float	R/W	Thickness
`PLA`	`NEL`	Float	R/W	Plastic strain
`OFF`	`NEL`	Float	R/W	Delete flag

Table 7. Engine User’s Arguments – Material Law for Bricks
Variable	Size	Type	Write/read	Definition
`NEL`	1	Integer	R	Number of elements
`UVAR`	`NUVAR`* `NEL`	Float	R/W	User’s variable
`UPARAM`	`NUPARAM`	Float	W	User’s parameter
`NUPARAM`	1	Integer	W	Size of `UPARAM`
`NUVAR`	1	Integer	W	Number of user’s variables
`NFUNCT`	1	Integer	W	Size of `IFUNC`
`IFUNC`	`NFUNCT`	Integer	W	Function number array
`NPF`	*	Integer	R	Function array
`TF`	*	Float	R	Function array
`NGL`	`NEL`	Integer	R	Element number
`TIME`	1	Float	R	Current time
`TIMESTEP`	1	Float	R	Current time step
`RHO0`	`NEL`	Float	R	Initial density
`RHO`	`NEL`	Float	R	Density
`VOLUME`	`NEL`	Float	R	Volume
`EINT`	`NEL`	Float	R	Total internal energy
`EPSPXX`	`NEL`	Float	W	Strain rate XX
`DEPSXX`	`NEL`	Float	W	Strain increment XX
`EPSXX`	`NEL`	Float	W	Strain XX
`SIGOXX`	`NEL`	Float	W	Old elasto-plastic stress XX
`SIGNXX`	`NEL`	Float	W	New elasto-plastic stress XX
`SIGVXX`	`NEL`	Float	W	Viscous stress XX
`SOUNDSP`	`NEL`	Float	W	Sound speed (time step)
`VISCMAX`	`NEL`	Float	W	Max damping modulus (time step)
`OFF`	`NEL`	Float	R/W	Delete flag

Table 8. Engine User’s Arguments – Spring Property
Variable	Size	Type	Write/read	Definition
`NEL`	1	Integer	R	Number of elements
`IPROP`	1	Integer	R	Property number
`UVAR`	`NUVAR`* `NEL`	Float	R/W	User’s variable
`NUVAR`	1	Integer	W	Number of user’s variables
`FX`	`NEL`	Float	R/W	Tension force
`FY`	`NEL`	Float	R/W	Y shear force
`FZ`	`NEL`	Float	R/W	Z shear force
`XMOM`	`NEL`	Float	R/W	Torsion moment
`YMOM`	`NEL`	Float	R/W	Y bending moment
`ZMOM`	`NEL`	Float	R/W	Z bending moment
`EINT`	`NEL`	Float	R/W	Total internal energy
`OFF`	`NEL`	Float	R/W	Delete flag
`STIFM`	`NEL`	Float	W	Element stiffness (time step)
`STIFR`	NEL	Float	W	Element rotation stiffness (time step)
`VISCM`	`NEL`	Float	W	Element viscosity (time step)
`VISCR`	`NEL`	Float	W	Element rotation viscosity (time step)
`MASS`	`NEL`	Float	W	Element mass
`XINER`	`NEL`	Float	W	Element inertia (spherical)
`DT`	1	Integer	R	Time step
`XL`	`NEL`	Float	R	Element length
`XL`	`NEL`	Float	R	Element length
`VX`	`NEL`	Float	R	Tension velocity
`RY1`	`NEL`	Float	R	Node 1 Y bending rotational velocity
`RZ1`	`NEL`	Float	R	Node 1 Z bending rotational velocity
`RX`	`NEL`	Float	R	Torsional velocity
`RY2`	`NEL`	Float	R	Node 2 Y bending rotational velocity
`RZ2`	`NEL`	Float	R	Node 2 Z bending rotational velocity

Table 9. Engine User’s Arguments
Variable	Size	Type	Write/read	Definition
`NEL`	1	Integer	R	Number of elements
`IOUT`	1	Integer	R	Output file unit (Engine output file)
`UVAR`	`NUVAR`* `NEL`	Float	R/W	User’s variable
`IPROP`	1	Integer	R	Property number
`IMAT`	1	Integer	R	Material number
`SOLID_ID`	`NEL`	Integer	R	Solid Element ID
`EINT`	`NEL`	Float	R	Total internal energy
`VOL`	`NEL`	Float	R	Initial volume
`OFF`	`NEL`	Float	R/W	Delete flag
`RHO`	`NEL`	Float	R/W	Density
`SIG`	6* `NEL`	Float	R/W	Stress tensor
`XX1`	`NEL`	Float	R	X coordinate node 1
`YY1`	`NEL`	Float	R	Y coordinate node 1
`ZZ1`	`NEL`	Float	R	Z coordinate node 1
`XX2` . . `ZZ8`	`NEL`	Float	R	Same for node 2 to 8
`VX1`	`NEL`	Float	R	X velocity node 1
`VY1`	`NEL`	Float	R	Y velocity node 1
`VZ1`	`NEL`	Float	R	Z velocity node 1
`VRX1`	`NEL`	Float	R	X rotational velocity node 1
`VRY1`	`NEL`	Float	R	Y rotational velocity node 1
`VRZ1`	`NEL`	Float	R	Z rotational velocity node 1
`FX1`	`NEL`	Float	W	X force node 1
`FY1`	`NEL`	Float	W	Y force node 1
`FZ1`	`NEL`	Float	W	Z force node 1
`MX1`	`NEL`	Float	W	X moment node 1
`MY1`	`NEL`	Float	W	Y moment node 1
`MZ1`	`NEL`	Float	W	Z moment node 1
`STIFM`	`NEL`	Float	W	Element stiffness (time step)
`STIFR`	`NEL`	Float	W	Element rotation stiffness (time step)
`VISCM`	`NEL`	Float	W	Element viscosity (time step)
`VISCR`	`NEL`	Float	W	Element rotation viscosity (time step)

Table 10. Engine User’s Arguments – Sensor
Variable	Size	Type	Write/read	Definition
`ID`	`NEL`	Integer	R	Sensor ID

Appendix 2 - Communication Between User's Subroutines and Radioss Code

The main functions to access user’s properties and materials are return functions and storage functions.

Return Function	Variables		Description
`INTEGER IP = GET_U_P(PID)`	`PID`	Integer property ID	Returns a property number.
`INTEGER PID = GET_U_PID(IP)`	`IP`	Property number	Returns the user property ID corresponding to the user property number `IP`.
`FLOAT PARAMI = GET U GEO (I,IP)`	`I`	Parameter index (1 for the first parameter, …)	Returns the user geometry parameters.
`FLOAT PARAMI = GET U GEO (I,IP)`	`IP`	Property number	Returns the user geometry parameters.
`INTEGER II = GET U PNU (I,IP,KK)` `IFUNCI = GET_U_PNU (I,IP,KFUNC)` `IPROPI = GET_U_PNU(I,IP,KPROP)` `IMATI = GET_U_PNU(I,IP,KMAT)`	`I`	Parameter index	Returns the user-stored function (if `KK`=`KFUNC`), material (if `KK`=`KMAT`), or property (if `KK`=`KPROP`) numbers. See Starter subroutine for corresponding ID storage.
	`IP`	Property number
	`KK`	Parameters `KFUNC`, `KMAT`, `KPROP`
`INTEGER IM = GET_U_M(MID)`	`MID`	Material ID	Returns a material number.
`INTEGER MID = GET_U_MID(IM)`	`IM`	Material number	Returns the user material ID corresponding to user material number `IM`.
`FLOAT PARAMI = GET_U_MAT(I,IM)`	`I`	Parameter index	Returns the user material parameters. Note: `GET_U_MAT(0,IMAT)` returns the density.
`FLOAT PARAMI = GET_U_MAT(I,IM)`	`IM`	Material number
`INTEGER IFUNCI = GET_U_MNU (I,IM,KFUNC)`	`I`	Variable index	Returns the user-stored function numbers (function referred by user’s materials). See the Starter material user’s subroutine for corresponding ID storage.
	`IM`	Material number
	`KFUNC`	Only functions are yet available
`FLOAT Y = GET_U_FUNC(IFUNC,X,DYDX)`	`IFUNC`	Function numbered obtained by `IFUNC = GET_U_MNU(I,IM, KFUNC`) or `IFUNC = GET_U_PNU(I,IP,KFUNC)`	Returns Y(X).
	`X`	X value
	`DYDX`	Slope dY/dX

Storage Function	Description
`INTEGER ierror = SET_U_PNU(func_index, fun_id, KFUNC)`	Stores Radioss function fun_id in the current user property buffer at a position referenced by `func_index`.
`INTEGER ierror = SET_U_PNU(mat_index, mid, KMAT)`	Stores Radioss material mid in the current user property buffer at a position referenced by `mat_index`.
`INTEGER ierror = SET_U_PNU(prop_index, pid, KPROP)`	Stores Radioss property pid in the current user property buffer at a position referenced by prop_index.
`INTEGER ierror = SET_U_GEO(value_index, value)`	Stores a value in the current user property buffer at a position referenced by `value_index`.

Specific functions for user's subroutines type sensor include:

Function	Variables		Description
`INTEGER NUM = GET_U_NUMSENS(ID)`	`ID`	Sensor ID	Allows you to get a sensor number.
`INTEGER NUM = GET_U_NUMSENS(ID)`	`NUM`	Sensor number	Allows you to get a sensor number.
`INTEGER ierror = GET_U_SENS_FPAR(IVAR, VAR)`	`IVAR`	Float variable index	Allows you to retrieve a float sensor parameter.
`INTEGER ierror = GET_U_SENS_FPAR(IVAR, VAR)`	`VAR`	Integer value	Allows you to retrieve a float sensor parameter.
`INTEGER ierror = GET_U_SENS_IPAR(IVAR, VAR)`	`IVAR`	Integer variable index	Allows you to retrieve an integer sensor parameter.
`INTEGER ierror = GET_U_SENS_IPAR(IVAR, VAR)`	`VAR`	Integer value	Allows you to retrieve an integer sensor parameter.
`INTEGER ierror = SET_U_SENS_VALUE(NSENS,IVAR,VAR)`	`NSENS`	Integer sensor number	Allows you to write a variable to a sensor buffer (float).
	`IVAR`	Integer buffer index
	`VAR`	Float value
`INTEGER ierror = GET_U_SENS_VALUE(NSENS,IVAR,VAR)`	`NSENS`	Integer sensor number	Allows you to read a variable from a sensor buffer (float).
	`IVAR`	Integer buffer index
	`VAR`	Float value
`INTEGER ierror = SET_U_SENS_ACTI(NSENS)`	`NSENS`	Integer sensor number	Allows you to activate a sensor using Radioss flag.
`FLOAT DTIME = GET_U_SENS_ACTI(NSENS)`	`DTIME`	Float time delay since first activation. `(actif < = > DTIME > 0)`	Allows you to check Radioss activation status of a sensor.
`FLOAT DTIME = GET_U_SENS_ACTI(NSENS)`	`NSENS`	Integer sensor number	Allows you to check Radioss activation status of a sensor.
`FLOAT TIME = GET_U_TIME()`			Allows you to check the current time.
`INTEGER NCYC = GET_U_CYCLE()`			Allows you to check the current cycle.
`INTEGER IERR = GET_U_ACCEL(NACC, AX,AY,AZ)`	`AX`, `AY`, `AZ`	Float acceleration components	Allows you to access accelerometer values.
	`NACC`	Integer accelerator number
	`IDACC`	Integer accelerator ID
	`NACC`	`GET_U_NUMACC(IDACC)`
`INTEGER IERR = GET_U_NOD_X(NOD, X,Y,Z)` `INTEGER IERR = GET_U_NOD_D(NOD, DX,DY,DZ)` `INTEGER IERR = GET_U_NOD_V(NOD, VX,VY,VZ)` `INTEGER IERR = GET_U_NOD_A(NOD, AX,AY,AZ)`	`X`, `Y`, `Z`	Float nodal coordinates	Allows you access to nodal values.
	`DX`, `DY`, `DZ`	Float nodal displacements
	`VX`, `VY`, `VZ`	Float nodal velocities
	`AX`, `AY`, `AZ`	Float nodal accelerations
	`NOD`	Integer node number
	`NID`	Integer node ID
	`NOD`	`GET_U_NUMNOD(ID)`
`FLOAT Y = GET_U_FUNC(IFUNC, X, DERI)`	`X`	Float ordinate	Allows you to access Radioss functions.
	`Y`	Float abscissa
	`DERI`	Float Y/X
	`IFUNC`	Integer function number
	`IDFUN`	Integer function ID, where `INTEGER IFUNC = GET_U_NUMFUN(IDFUN)`

Communication Between User's Modules and Radioss Database

Appendix 3 - General User's Subroutine Format with Material Laws 29, 30, and 31

Starter Format Example

Engine Format Example

Example Demo File

Refer to Access the Model Files to download the required model file(s).

Appendix 4 - General User's Subroutine Format with Extended User Material Laws

Starter Format Example

Engine Format Example

Example Demo File

Refer to Access the Model Files to download the required model file(s).