Block Format Keyword This option is used to read fiber orientation changes and thinning for a ply which are usually the result a manufacturing process simulation. Each line defines the angle change and the thinning for either a single element or a group. Each element of the ply can only be called once for a single DRAPE option.


(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
For each entity per line
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
Entity Entity_ID Thinning θ drape        


Field Contents SI Unit Example
drape_ID Drape identifier

(Integer, maximum 10 digits)

drape_title Drape title

(Character, maximum 100 characters)

Entity Must be left justified.
The entity is a 4 nodes shell element.
The entity is a 3 nodes shell element.
The entity is a group of 4 nodes shell element.
The entity is a group of 3 nodes shell element.


Entity_ID Entity identifier


Thinning Ply thinning factor


θ drape Ply orientation change


[ deg ]


  1. The drape is used in /PLY and /PROP/TYPE19 (PLY) to take into account the manufacturing process on the ply orientation and thickness of the elements. See Example (Substack with /DRAPE) in /STACK.
  2. For each shell element, the ply first orthotropy direction is rotated by an angle θ drape in addition to the angles defined in the /PROP/PLY and /PLY or in the shell definition (depending of the value of flag def_orth in the ply input):
    If def_orth = 2, the angle for between the reference direction and the first direction of orthotropy is:(1)
    ϕ = ϕ i + Δ ϕ + θ d r a p e MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbbG8FasPYRqj0=yi0dXdbba9pGe9xq=JbbG8A8frFve9 Fve9Ff0dmeaabaqaciGacaGaaeqabaWaaeaaeaaakeaacqaHvpGzcq GH9aqpcqaHvpGzdaWgaaWcbaGaamyAaaqabaGccqGHRaWkcaqGuoGa eqy1dyMaey4kaSIaeqiUde3aaSbaaSqaaiaadsgacaWGYbGaamyyai aadchacaWGLbaabeaaaaa@4745@
    Where, ϕ i is defined in the /STACK or /PROP/TYPE17 (STACK) for ply layer i and Δ ϕ is the angle of rotation of the layer with respect to the shell defined in the /PLY or /PROP/PLY option.

    Figure 1.
    If def_orth = 1, the angle between the shell skew (take the shell local x-axis as vector V ' MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaCOvaiaacE caaaa@3780@ ) and the first direction of orthotropy is:(2)
    ϕ = ϕ s + Δ ϕ + θ drape

    Where, ϕ s is defined in the shell (/SHELL or /SH3N) and Δ ϕ is the angle of rotation of the layer with respect to the shell, defined in the /PLY or /PROP/PLY option. See Example (Substack with /DRAPE) in /STACK.

    If def_orth =1, skew_ID, VX, VY, and VZ from the /PROP/TYPE17, /PROP/TYPE51 and /STACK input are ignored.

  3. The ply thickness ti of the element as defined in the ply is scaled using the ply thinning factor Thinning.