python implementation of a 3D Vortex Lattice Method for upwind sails
The geometry is described using the following CSYS.
lem - leading edge (luff) of the main sail
tem - trailing edge (leech) of the main sail
Z ^ (mast)
|
/|
/ |
/ | ^ Y
lem_NW +--+tem_NE /
/ | \ /
/ | \ /
/ | \ /
/ | \ /
/ | \/
/ | /\
/ | / \
/ | / \
/ | / \
/ lem_SW |---/--------+tem_SE
/ | /
(bow) ------------------|-/-------------------------| (stern)
\ |/ |
------\---------------*---------------------------|-------------------------> X (water level)
Run:
git clone https://github.com/ggruszczynski/sailingVLM.git
cd SailingVLM
pip install -r requirements.txt
python Examples/jib_and_main_sail_vlm_runner.py
Sample output:
Notice:
The forces [N] and moments [Nm] are without profile drag.
The the _COG_ CSYS is aligned in the direction of the yacht movement (course over ground).
The the _COW_ CSYS is aligned along the centerline of the yacht (course over water).
Number of panels per sail: 15 x 10
Quantity Value
0 F_jib_total_COG.x -266.683479
1 F_jib_total_COG.y 646.602335
2 F_jib_total_COG.z -44.590695
3 F_main_sail_total_COG.x -385.603864
4 F_main_sail_total_COG.y 1137.121372
5 F_main_sail_total_COG.z -215.927101
6 F_sails_total_COG.x -652.287343
7 F_sails_total_COG.y 1783.723706
8 F_sails_total_COG.z -260.517796
9 F_sails_total_COW.x -805.266957
10 F_sails_total_COW.y 1720.085511
11 F_sails_total_COW.z -260.517796
12 M_jib_total_COG.x -3362.589632
13 M_jib_total_COG.y -1569.839224
14 M_jib_total_COG.z -835.530200
15 M_keel_total_COG.x -1801.691230
16 M_keel_total_COG.y -646.320422
17 M_keel_total_COG.z 85.841835
18 M_keel_total_COW.x (heel) -1738.504714
19 M_keel_total_COW.y (pitch) -800.888715
20 M_keel_total_COW.z (yaw) 85.841835
21 M_main_sail_total_COG.x -10150.594134
22 M_main_sail_total_COG.y -3271.189461
23 M_main_sail_total_COG.z 2534.256594
24 M_sails_total_COG.x -13513.183766
25 M_sails_total_COG.y -4841.028686
26 M_sails_total_COG.z 1698.726394
27 M_sails_total_COW.x (heel) -13039.838572
28 M_sails_total_COW.y (pitch) -6000.358678
29 M_sails_total_COW.z (yaw) 1698.726394
30 M_total_COG.x -15314.874996
31 M_total_COG.y -5487.349108
32 M_total_COG.z 1784.568230
33 M_total_COW.x (heel) -14778.343286
34 M_total_COW.y (pitch) -6801.247393
35 M_total_COW.z (yaw) 1784.568230
CPU time: 12.43 [s]