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LEPARAGLIDING 2.52++
PRE-PROCESSOR OF GEOMETRY 1.4 (OPTIONAL)



GEOMETRY PRE-PROCESSOR for use with leparagliding.txt input file of LEparagliding 2.52++
Version 1.0 "Kemerovo" (2013-06-16)
Version 1.1 "Kemerovo" (2013-06-24)
Version 1.2 "Gurzuf" (2015-09-05)
Version 1.3 "Utah" (2016-04-17)
Version 1.4 "Escaules" (2016-08-24)

This preprocessor is an optional module for use with LEparagliding. Only serves to help generate the geometry matrix of the wing, which can also be generated by drawing directly into a CAD program or even manually with pencil and paper, as before. Its main application is in the definition of paragliders with many cells, where there is a lot of manual work definition. To generate complex geometries (different from normal) is always necessary manual labor, but the array generated can serve as a basis.

BASIC INSTRUCTIONS:

INPUT FILE:

    pre-data.txt 

Fill in the data file with the geometric parameters (
details below) that define the main curves of the wing, leading edge, trailing edge, and main vault.
Choose and define a distribution of cells along span.


OUTPUT FILES:

    geometry.dxf --> DXF containig planview, and distribution of cells, main vault

    geometry-out.txt --> TXT file containig matrix of geometry for use with LEparagliding 2.2 input file leparagliding.txt section 1. GEOMETRY
                                       Auxiliar geometry matrix for use with LEparagliding 2.2:
                                       Rib    x-rib      y-LE       y-TE       xp    z    beta      RP        Washin


SOURCE CODE:

    pre-processor.f --> GNU Fortran source code :-) !

EXECUTABLE FILES:

    a.exe (windows version, use with cygwin1.dll in the same directory)

    a.out (GNU/Linux)

    Download all files and executable here: pre-processor.zip

DESCRIPTION OF A TYPICAL INPUT DATA FILE pre-data.txt:

**********************************
LEPARAGLIDING
GEOMETRY PRE-PROCESSOR     v1.4
**********************************
gnu-A
**********************************
* 1. Leading edge parameters
**********************************
a1= 609.68
b1= 223.58
x1= 291.5
xm= 539
c0= 40
**********************************
* 2. Trailing edge parameters
**********************************
a1= 636.925
b1= 127.97
x1= 352.77
xm= 539
c0= -3.834
y0= 42.22
**********************************
* 3. Vault
**********************************
2
640.56    20.35
480.47    21.367
229.50    18.925
99.26    28.349
**********************************
* 4. Cells distribution
**********************************
3
0.3
27


Sections 1. 2. and 3. change parameters acording figures below.

Section 3. Vault.
If first number is "1" then vault using ellipse and cosinus modification, indicate parameters a1, b1,
If first number is "2" then vault using four tangent circles. In four rows indicate radious and angle (deg).

Section 4. Cells distribution
- First number "3" indicates cell width proportional to chord
- Second number is a coefficient between "0.0" and "1.0". If coefficient is "0" then cell width is estrictly proportional to the chord, using iterative calculus. If coefficient is set to "1.0", then cell width is uniform. Use intermediate values as you need.
- Third number is the total cell number.
If first number is "4" then we use explicit width of each cell with automatic adjustement, if the sum not match the span (view examples).

pre-data.txt Example NOTES:
pre-data example The first step is to draw on a CAD program (or even manually with pencil and paper), the main curves of the wing: leading edge, trailing edge, vault, and then deduce the geometric parameters to insert in the input file pre-data.txt.

The program includes a routine to automatically adjust the length of the vault to the length of the wing in planview (span). So if the length of the vault is introduced slightly larger or smaller than the total width of the wing, does not matter, because it is adjusted to the span=2*Xm.

Then run the program:
a.exe (WIndows 32-bit) or
./a.out (GNU/Linux)

geometry.dxf file is
just to confirm that the data entered are the desired

Then open geometry-output.txt file
and copy (and modify if necessary) the matrix of geometry for use with LEparagliding 2.2 input file (leparagliding.txt section 1. GEOMETRY)

Rib    x-rib      y-LE       y-TE       xp    z    beta      RP        Washin


FIGURES: GEOMETRIC PARAMETERS DETAILS

Note: to complete the pre-data.txt file, you only need to know to identify what are the geometric parameters a1, b1, x1, xm, c, y0 ... indicated in the accompanying figures. The mathematical description is additional detail (just  to satisfy the curiosity of students of mathematics) as implemented in the Fortran source code of the program.

Main parameters for leading edge, trailing edge, and vault:
leading edge
trailing edge

vault

Alternative vault using four tangent circles
Vault 4c

vault 4c
vault 4c
vault 4c

Cell widths proporcional to chord and using control coefficient k from 0.0 (full proportional) to 1.0 (uniform width)
cells distribution
cells distribution
cells distribution
cells distribution
index