/IMPVEL

Block Format Keyword Defines imposed velocities on a group of nodes.

Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
/IMPVEL/impvel_ID/unit_ID
impvel_title
fct_IDT Dir Skew_ID sens_ID grnd_ID frame_ID icoor
Ascalex FscaleY Tstart Tstop

Definition

Field Contents SI Unit Example
impvel_ID Imposed velocity block identifier.

(Integer, maximum 10 digits)

unit_ID Unit identifier

(Integer, maximum 10 digits)

impvel_title Imposed velocity block title.

(Character, maximum 100 characters)

fct_IDT Time function identifier.

(Integer)

Dir Direction: X, Y, and Z in translation; XX, YY, and ZZ in rotation.

(Text)

Skew_ID Skew identifier.
0
The imposed velocity is computed in the global frame and projected onto the local skew.

(Integer)

sens_ID Sensor identifier.
0 (sensor activated)
The imposed velocity is applied after sensor activation. The time function is shifted by the sensor activation time.

(Integer)

grnd_ID Node group on which the imposed velocity is applied.

(Integer)

frame_ID Frame identifier.
0
The imposed velocity is computed and applied in the local frame.

(Integer)

icoor Coordinate system usage type.
= 0
Cartesian coordinates.
= 1
Cylindrical coordinates.

(Integer)

Ascalex Abscissa (time) scale factor for fct_IDT.

Default = 1.0 (Real)

[ s ]
FscaleY Ordinate (velocity) scale factor for fct_IDT.

Default = 1.0 (Real)

[ m s ] MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaamWaaeaada Wcaaqaaiaab2gaaeaacaqGZbaaaaGaay5waiaaw2faaaaa@39DE@ or [ rad s ]
Tstart Start time.

(Real)

[ s ]
Tstop Stop time.

Default = 1030 (Real)

[ s ]

Comments

  1. The velocity direction must be right justified in the ten characters of field number 2.
  2. If a velocity is imposed in a frame (frame_ID ≠ 0), the frame nodes must not have an imposed velocity themselves.
  3. If Tstart and Tstop are specified, the velocity is imposed between these times, but the time versus velocity function is not shifted to begin at Tstart.
  4. When a sensor is defined sens_ID, the imposed velocity is applied at the time of sensor activation and the function is shifted by the sensor activation time.
  5. When a sensor sens_ID is used with Tstart and Tstop, the imposed velocity will only occur if the sensor activation time occurs between Tstart and Tstop.
  6. The AscaleX and FscaleY are used to scale the abscissa (time) and ordinate (translational or angular velocity).

    The actual load function value is calculated as:

    F ( t ) = F s c a l e y f T ( t A s c a l e x ) MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbwvMCKf MBHbqefqvATv2CG4uz3bIuV1wyUbqedmvETj2BSbqefm0B1jxALjhi ov2DaebbnrfifHhDYfgasaacH8akY=xipgYlh9vqqj=hEeei0xXdbb a9frFf0=yqFf0dbba91qpepeI8k8fiI+fsY=rqaqpepae9pg0Firpe pesP0xe9Fve9Fve9qapdbaGaaiGadiWaamaaceGaaqaacaqbaaGcba GaciOraiGacIcacaWG0bGaaiykaiabg2da9iaadAeacaWGZbGaam4y aiaadggacaWGSbGaamyzamaaBaaaleaacaWG5baabeaakiabgwSixl GacAgadaWgaaWcbaGaamivaaqabaGcdaqadaqaamaalaaabaGaamiD aaqaaiaadgeacaWGZbGaam4yaiaadggacaWGSbGaamyzamaaBaaale aacaWG4baabeaaaaaakiaawIcacaGLPaaaaaa@520D@

    Where, f T MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbwvMCKf MBHbqefqvATv2CG4uz3bIuV1wyUbqedmvETj2BSbqefm0B1jxALjhi ov2DaebbnrfifHhDYfgasaacH8akY=xipgYlh9vqqj=hEeei0xXdbb a9frFf0=yqFf0dbba91qpepeI8k8fiI+fsY=rqaqpepae9pg0Firpe pesP0xe9Fve9Fve9qapdbaGaaiGadiWaamaaceGaaqaacaqbaaGcba GaciOzamaaBaaaleaacaWGubaabeaaaaa@3BC7@ is the function of fct_IDT.

  7. SKEW and FRAME cannot be defined together. This is SKEW or FRAME.
  8. If icoor=1, the directions X, Y, and Z (resp. XX, YY, and ZZ) refer to translations along (resp. rotations around) the radial direction (r), azimuthal angular direction ( θ ) and longitudinal direction (Z) (refer to /SKEW/FIX and /FRAME/FIX).
    Figure 1.

    cyl_coord_system
  9. If icoor=1 when imposing the translational velocity in the radial, resp. the azimuthal direction, the velocity of the node is set so that:
    r ˙ = F s c a l e y f T ( t A s c a l e x ) MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbwvMCKf MBHbqefqvATv2CG4uz3bIuV1wyUbqedmvETj2BSbqefm0B1jxALjhi ov2DaebbnrfifHhDYfgasaacH8akY=xipgYlh9vqqj=hEeei0xXdbb a9frFf0=yqFf0dbba91qpepeI8k8fiI+fsY=rqaqpepae9pg0Firpe pesP0xe9Fve9Fve9qapdbaGaaiGadiWaamaaceGaaqaacaqbaaGcba GabmOCayaacaGaeyypa0JaaGjbVlaadAeacaWGZbGaam4yaiaadgga caWGSbGaamyzamaaBaaaleaacaWG5baabeaakiabgwSixlGacAgada WgaaWcbaGaamivaaqabaGcdaqadaqaamaalaaabaGaamiDaaqaaiaa dgeacaWGZbGaam4yaiaadggacaWGSbGaamyzamaaBaaaleaacaWG4b aabeaaaaaakiaawIcacaGLPaaaaaa@517A@
    r e s p . θ ˙ = F s c a l e y f T ( t A s c a l e x ) MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbwvMCKf MBHbqefqvATv2CG4uz3bIuV1wyUbqedmvETj2BSbqefm0B1jxALjhi ov2DaebbnrfifHhDYfgasaacH8akY=xipgYlh9vqqj=hEeei0xXdbb a9frFf0=yqFf0dbba91qpepeI8k8fiI+fsY=rqaqpepae9pg0Firpe pesP0xe9Fve9Fve9qapdbaGaaiGadiWaamaaceGaaqaacaqbaaGcba GaamOCaiaadwgacaWGZbGaamiCaiaac6cacaaMe8UafqiUdeNbaiaa cqGH9aqpcaaMe8UaamOraiaadohacaWGJbGaamyyaiaadYgacaWGLb WaaSbaaSqaaiaadMhaaeqaaOGaeyyXICTaciOzamaaBaaaleaacaWG ubaabeaakmaabmaabaWaaSaaaeaacaWG0baabaGaamyqaiaadohaca WGJbGaamyyaiaadYgacaWGLbWaaSbaaSqaaiaadIhaaeqaaaaaaOGa ayjkaiaawMcaaaaa@5846@

    with v = r ˙ e r r + r θ ˙ e θ + z ˙ e z MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbwvMCKf MBHbqefqvATv2CG4uz3bIuV1wyUbqedmvETj2BSbqefm0B1jxALjhi ov2DaebbnrfifHhDYfgasaacH8akY=xipgYlh9vqqj=hEeei0xXdbb a9frFf0=yqFf0dbba91qpepeI8k8fiI+fsY=rqaqpepae9pg0Firpe pesP0xe9Fve9Fve9qapdbaGaaiGadiWaamaaceGaaqaacaqbaaGcba GaaCODaiabg2da9iqadkhagaGaaiaadwgadaWgaaWcbaGaamOCaaqa baGccaWGYbGaey4kaSIaamOCaiqbeI7aXzaacaGaamyzamaaBaaale aadaWgaaadbaGaeqiUdehabeaaaSqabaGccqGHRaWkceWG6bGbaiaa caWGLbWaaSbaaSqaaiaadQhaaeqaaaaa@4A8E@