Property File
Aerodynamic system uses aerodynamic property file (.aae) to provide access to all the parameters to the solver. The reference to the .aae file is sent to the solver as a Solver String in the sa_aero_params solver array.
 TiemOrbit Format
 The TeimOrbit reader can parse various entities to get data from the aerodynamic
property file. These entities include: attributes, blocks, subblocks, tables, units,
and comments.
 Attributes
 Attributes form the smallest data member of the driver file. Attributes can be
real, integer, strings or Booleans (True/False).
[BLOCK_NAME] ATTRIBUTE_1 = 'TRUE' ATTRIBUTE_2 = 1.0 ATTRIBUTE_3 = 'Wind_velocity' ATTRIBUTE_4 = 8
Attribute names are: Strings
 Case insensitive, for example: TAG and tag are equivalent.
 In the above example, the attributes are: TAG, SATURATION, LOOK_AHEAD_TIME, DEMAND_FILE, INTEGRATION_STEP_SIZE are the attribute names.
Attribute value: Real, integer, string, bool
 Strings should be written in ‘single quotes’ or “double quotes”
 0, 0.00, N, NO, FALSE, F are all depicted as false
 1, 1.00, T, TRUE, Y, YES are all depicted as true
 Case sensitive
Format:ATTRIBUTE_NAME = ATTRIBUTE_VALUE
 Block
 Blocks form the most versatile data structure of the reader utility. It acts
as container for all other data members except a block.
 Block can contain any number of subblocks.
 Block cannot contain a block.
 Block can contain multiple tables but only storing them in different subblocks.
Format:[BLOCK_NAME] ATTRIBUTE(s) SUBBLOCK(s) TABLE
Block ends with the end of file or start of new Block.
 Subblock
 Subblocks are structurally similar to blocks with an only difference that
they cannot contain sub blocks or blocks.
 A sub block cannot contain more than one table.
Format:(SUBBLOCK_NAME) ATTRIBUTE(s) TABLE(s)
 Table

Data structure which consists of fields (rows and columns).
 Table can contain any type of attributes.
 In no label is provided, the default is to label them as indices starting from 0.
Format:{LABEL_{1} LABEL_{2} LABEL_{3}} ATTRIBUTE_{00} ATTRIBUTE_{01} ATTRIBUTE_{02} ATTRIBUTE_{10} ATTRIBUTE_{11} ATTRIBUTE_{12} ATTRIBUTE_{20} ATTRIBUTE_{21} ATTRIBUTE_{22 }
 Units

‘Units’ is a special block that conveys the reader units of the property file.
 Every property sheet should necessarily have a units block.
 User defined units in tables.
 Comment
 Anything written in line after ‘$’ is ignored by the reader
utility.
[ENVIRONMENT] $These are environment conditions for the simulation GAS_CONSTANT = 287e3 AMBIENT_PRESSURE = 0.101325 AMBIENT_TEMPERATURE = 298 WIND_VELOCITY = 'WIND_VELOCITY'
 Altair Header
 The Altair header block provides the basic information of the property file to the
solver.
$ALTAIR_HEADER [ALTAIR_HEADER] FILE_TYPE = 'AAE' FILE_VERSION = 1.0 FILE_FORMAT = 'ASCII' ENTITY_TYPE = 'AERODYNAMIC_FORCE'
Type Requirement Block name
[ALTAIR_HEADER]String REQUIRED FILE_TYPE AttrString REQUIRED  Read and extract information
 Multiple file format support
FILE_VERSION AttrReal REQUIRED FILE_FORMAT
‘ASCII’AttrString OPTIONAL
Optional currently, required for future enhancement.ENTITY_TYPE
'AERODYNAMIC_FORCE'AttrString OPTIONAL
Provides info on the entity associated with the property file.  Units
 Solver parses the AAE in MotionSolve during the simulation to extract aerodynamic
and environment data. While parsing the property file, solver reads the units block to
convert data in the property file to SI units and use them further in the
simulation.Units block specifies the units of all the data mentioned in the property file. The units are specified for length, force, angle, mass, time and temperature.
 Units are not case sensitive – meter, Meter, METER, or MeTer are all interpreted as same.
 Units block is require for all types of data files.
$UNITS [UNITS] (BASE) {length force angle mass time temperature} 'mm' 'newton' 'degrees' 'kg' 'sec' 'kelvin'
Dimension Options Conversion Factor to SI Length meter or meters or m
foot or feet or ft
mile or miles
millimeter or millimeters or mm
inch or inches or in1.0
0.3048
1609.344
0.001
0.0254Force Newton
Dyne
KNewton
Ounce_Force
Kilogram_Force or Kgf
KPound_Force
Pound_Force or lbf
1.0
0.00001
1000
0.27801
9.80665
4448.2216
4.4482216Angle Radian or radians or rad or r
Degrees or degree or deg or d1.00
0.017453Mass Kg or kilogram or kilograms
G or gram or grams
Pound or pounds or lb or lbs1.0
0.001
0.453592Time sec or second or seconds
milliseconds or millisecond or millisec or millisecs or ms1.0
0.001Temperature Kelvin or k
Note: More temperature units will be supported in upcoming versions.1.0  Geometric properties
 This section contains the data related to vehicle geometry. Calculation of the
aerodynamic forces require the frontal area of the vehicle which is specified in this
block.
$GEOMETRIC_PROPERTIES [GEOMETRIC_PROPERTIES] FRONTAL_SECTION_AREA = 2e6
Block name
[GEOMETRIC_PROPERTIES]String REQUIRED FRONTAL_SECTION_AREA AttrReal REQUIRED
Frontal area of the vehicle.
Unit – L^{2}  Environment
 This section contains the data related to the environment. Calculation of the
aerodynamic forces require the ambient pressure, ambient temperature and wind velocity
which is specified in this
block.
$ENVIRONMENT [ENVIRONMENT] GAS_CONSTANT = 287e3 AMBIENT_PRESSURE = 0.101325 AMBIENT_TEMPERATURE = 298 WIND_VELOCITY = 'WIND_VEL_1' $Wind vel is with respect to global frame $WIND_VELOCITY [WIND_VEL_1] $Wind vel is with respect to global frame VX = 1000 VY = 0 VZ = 0
Type Requirement Block name
[ENVIRONMENT]String REQUIRED GAS_CONSTANT AttrReal REQUIRED
Unit – FLM^{1}Temp^{1}AMBIENT_PRESSURE AttrReal REQUIRED
Unit – FL^{2}AMBIENT_TEMPERATURE AttrReal REQUIRED
Unit – TempWIND_VELOCITY
AttrSTRING Reference to another block having wind velocities (Vx, Vy, Vz)
REQUIRED
Unit – LT^{1}  Drag Coefficient
 This section contains the table of drag coefficients with respect to different
incidence angles. The table is provided as a spline as shown in the block and the
interpolation scheme is provided. This block is applicable for both threepoint and
singlepoint
implementation.
$DRAG_COEFFICIENT [DRAG_COEFFICIENT] INTERPOLATION = 'AKIMA' (SPLINE_DATA) {INCIDENCE_ANGLE COEFFICIENT} 0.0 0.3 10.0 0.31 20.0 0.32 30.0 0.33
Type Requirement Block name
[DRAG_COEFFICIENT]String REQUIRED INTERPOLATION AttrString OPTIONAL
If absent: Interpolation scheme = AKIMA
If present: Interpolation scheme = INTERPOLATION.value.
 Options  AKIMA, CUBIC, LINEAR, QUINTIC.
These interpolation schemes are similar to those of Altair MotionSolve. See the Altair MotionSolve documentation for details on interpolation schemes.
SPLINE_DATA AttrTable
INCIDENCE_ANGLE vs COEFFICIENTREQUIRED
Drag coefficient values at different values of incidence angles
 Side Force Coefficient
 This section contains the table of sideforce coefficients with respect to different
incidence angles. The table is provided as a spline as shown in the block and the
interpolation scheme is provided. This block is applicable for both threepoint and
singlepoint
implementation.
$ SIDEFORCE_COEFFICIENT [SIDEFORCE_COEFFICIENT] INTERPOLATION = 'AKIMA' (SPLINE_DATA) {INCIDENCE_ANGLE COEFFICIENT} 0.0 0.3 10.0 0.31 20.0 0.32 30.0 0.33
Type Requirement Block name
[SIDEFORCE_COEFFICIENT]String REQUIRED INTERPOLATION AttrString OPTIONAL
If absent: Interpolation scheme = AKIMA
If present: Interpolation scheme = INTERPOLATION.value.
 Options  AKIMA, CUBIC, LINEAR, QUINTIC.
These interpolation schemes are similar to those of Altair MotionSolve. See the Altair MotionSolve documentation for details on interpolation schemes.
SPLINE_DATA AttrTable
INCIDENCE_ANGLE vs COEFFICIENTREQUIRED
Sideforce coefficient values at different values of incidence angles
 Lift Coefficient
 This section contains the table of front lift coefficients with respect to different
incidence angles. The table is provided as a spline as shown in the block and the
interpolation scheme is provided. This block is only applicable for singlepoint
implementation.
$ LIFT_COEFFICIENT [LIFT_COEFFICIENT] INTERPOLATION = 'AKIMA' (SPLINE_DATA) {INCIDENCE_ANGLE COEFFICIENT} 0.0 0.3 10.0 0.31 20.0 0.32 30.0 0.33
Type Requirement Block name [LIFT_COEFFICIENT]
String REQUIRED INTERPOLATION AttrString OPTIONAL
If absent: Interpolation scheme = AKIMA
If present: Interpolation scheme = INTERPOLATION.value.
 Options  AKIMA, CUBIC, LINEAR, QUINTIC.
These interpolation schemes are similar to those of Altair MotionSolve. See the Altair MotionSolve documentation for details on interpolation schemes.
SPLINE_DATA AttrTable
INCIDENCE_ANGLE vs COEFFICIENTREQUIRED
Front lift coefficient values at different values of incidence angles
 Front Lift Coefficient
 This section contains the table of front lift coefficients with respect to different
incidence angles. The table is provided as a spline as shown in the block and the
interpolation scheme is provided. This block is only applicable for threepoint
implementation.
$ LIFT_COEFFICIENT_FRONT [LIFT_COEFFICIENT_FRONT] INTERPOLATION = 'AKIMA' (SPLINE_DATA) {INCIDENCE_ANGLE COEFFICIENT} 0.0 0.3 10.0 0.31 20.0 0.32 30.0 0.33
Type Requirement Block name [LIFT_COEFFICIENT_FRONT]
String REQUIRED INTERPOLATION AttrString OPTIONAL
If absent: Interpolation scheme = AKIMA
If present: Interpolation scheme = INTERPOLATION.value.
 Options  AKIMA, CUBIC, LINEAR, QUINTIC.
These interpolation schemes are similar to those of Altair MotionSolve. See the Altair MotionSolve documentation for details on interpolation schemes.
SPLINE_DATA AttrTable
INCIDENCE_ANGLE vs COEFFICIENTREQUIRED
Front lift coefficient values at different values of incidence angles
 Rear Lift Coefficient
 This section contains the table of rear lift coefficients with respect to different
incidence angles. The table is provided as a spline as shown in the block and the
interpolation scheme is provided. This block is only applicable for threepoint
implementation.
$ LIFT_COEFFICIENT_REAR [LIFT_COEFFICIENT_REAR] INTERPOLATION = 'AKIMA' (SPLINE_DATA) {INCIDENCE_ANGLE COEFFICIENT} 0.0 0.3 10.0 0.31 20.0 0.32 30.0 0.33
Type Requirement Block name [LIFT_COEFFICIENT_REAR]
String REQUIRED INTERPOLATION AttrString OPTIONAL
If absent: Interpolation scheme = AKIMA
If present: Interpolation scheme = INTERPOLATION.value.
 Options  AKIMA, CUBIC, LINEAR, QUINTIC.
These interpolation schemes are similar to those of Altair MotionSolve. See the Altair MotionSolve documentation for details on interpolation schemes.
SPLINE_DATA AttrTable
INCIDENCE_ANGLE vs COEFFICIENTREQUIRED
Rear lift coefficient values at different values of incidence angles
 Roll Coefficient
 This section contains the table of roll coefficients with respect to different
incidence angles. The table is provided as a spline as shown in the block and the
interpolation scheme is provided. This block is only applicable for threepoint
implementation.
$ ROLL_COEFFICIENT [ROLL_COEFFICIENT] INTERPOLATION = 'AKIMA' (SPLINE_DATA) {INCIDENCE_ANGLE COEFFICIENT} 0.0 0.3 10.0 0.31 20.0 0.32 30.0 0.33
Type Requirement Block name [ROLL_COEFFICIENT]
String REQUIRED INTERPOLATION AttrString OPTIONAL
If absent: Interpolation scheme = AKIMA
If present: Interpolation scheme = INTERPOLATION.value.
 Options  AKIMA, CUBIC, LINEAR, QUINTIC.
These interpolation schemes are similar to those of Altair MotionSolve. See the Altair MotionSolve documentation for details on interpolation schemes.
SPLINE_DATA AttrTable
INCIDENCE_ANGLE vs COEFFICIENTREQUIRED
Roll coefficient values at different values of incidence angles
 Yaw Coefficient

This section contains the data related to vehicle geometry. Calculation of the aerodynamic forces require the frontal area of the vehicle which is specified in this block. This block is only applicable for threepoint implementation.
$ YAW_COEFFICIENT [YAW_COEFFICIENT] INTERPOLATION = 'AKIMA' (SPLINE_DATA) {INCIDENCE_ANGLE COEFFICIENT} 0.0 0.3 10.0 0.31 20.0 0.32 30.0 0.33
Type Requirement Block name [YAW_COEFFICIENT]
String REQUIRED INTERPOLATION AttrString OPTIONAL
If absent: Interpolation scheme = AKIMA
If present: Interpolation scheme = INTERPOLATION.value.
 Options  AKIMA, CUBIC, LINEAR, QUINTIC.
These interpolation schemes are similar to those of Altair MotionSolve. See the Altair MotionSolve documentation for details on interpolation schemes.
SPLINE_DATA AttrTable
INCIDENCE_ANGLE vs COEFFICIENTREQUIRED
Yaw coefficient values at different values of incidence angles