Dear @peterdsharpe,

I am planning on using your library to finish some assignments for an aerodynamical course.

Do you reckon it would be possible to simulate a wing with a winglet, to compute it's induced drag?

If the code does not support it yet, would you have an idea on how to do it, so I can implement it, use it and then merge it to your master branch?

Thank you.

Hi @peterdsharpe, I was validating the code with avl and I found that the moments estimated from this code is way off. Upon looking at vlm3.py I found the formula for moments are incorrect. Could you please check and confirm with it.

Bug Description

When running 01 - AVL.ipynb AVL produces the following error:

 Reading file: airplane.avl  ...

 Configuration: Example Airplane                                            

   Building surface: Wing                                    
At line 629 of file ../src/ainput.f
Fortran runtime error: End of file

Error termination. Backtrace:
#0  0x7f67df8dcd5a
#1  0x7f67df8dd869
#2  0x7f67df8de54f
#3  0x7f67dfb21c5b
#4  0x7f67dfb1b15c
#5  0x7f67dfb1bdc9
#6  0x5606701ea350
#7  0x5606701cb015
#8  0x5606701cc652
#9  0x7f67df5870b2
#10  0x5606701c86bd
#11  0xffffffffffffffff

Steps to Reproduce

1. I first installed AVL using steps found here: https://ubuntuforums.org/showthread.php?t=2274062
2. Added AVL to system path.
3. Ran ~~01 - Basic Aircraft Geometry.ipynb~~ 01 - AVL.ipynb

System Information

• Operating System: Ubuntu 20.04
• Python Version: 3.9
• AeroSandbox Verion: 3.3.0
• AVL Version: 3.32

Other Information

I tested AVL on the supergee.avl example and obtained the following plots, so I am confident it is installed correctly.

Bug Description

Trying to run example script from the readme

Steps to Reproduce

Install package (either local or with pypi, tried both) Copy script from readme Run program

Expected Behavior

Produce images from readme, instead there is some incompatibility with WingXSec, these are easily fixed.

However, VLM3 is not found, and the existing example uses only airplane and op_point, while the current implementation also expects an "opti" param. I'm not sure how to incorporate this?

System Information

• Operating System: MacOS
• Python Version: 3.7.0
• AeroSandbox Verion: 3.0.11

Other Information

Thanks! Would love to experiment with this program more, but need a basis to work off. I am trying to do some analysis for different car wing setups (single + dual element). Mostly interested in doing L/D analysis for various airfoil designs.

Anything to get me in the right direction would be appreciated! Thanks!

Hey @antoniosgeme ! This unsteady aero library looks really solid, awesome work!

I'm creating this PR just as a bookmark to remind us to merge this at some point down the line when you feel it's ready. No rush at all, and thanks for the great contributions!

-Peter

Hi, i'm quite new to this but have been having problems getting anything to run as any example i run comes up with ModuleNotFoundError: No module named 'plotly'. I have installed various versions of plotly to try and get it to work but it hasn't. Any help would be appreciated.

Python 3.8.2 (v3.8.2:7b3ab5921f, Feb 24 2020, 17:52:18) [Clang 6.0 (clang-600.0.57)] on darwin Type "help", "copyright", "credits" or "license()" for more information.

= RESTART: /Users/bradleyrelyea/Desktop/AeroSandbox-1.1.5/casvlm1_conventional_analysis_alpha_sweep.py Traceback (most recent call last): File "/Users/bradleyrelyea/Desktop/AeroSandbox-1.1.5/casvlm1_conventional_analysis_alpha_sweep.py", line 3, in from aerosandbox import * File "/Users/bradleyrelyea/Desktop/AeroSandbox-1.1.5/aerosandbox/init.py", line 1, in from .aerodynamics import * File "/Users/bradleyrelyea/Desktop/AeroSandbox-1.1.5/aerosandbox/aerodynamics/init.py", line 1, in from .casvlm1 import * File "/Users/bradleyrelyea/Desktop/AeroSandbox-1.1.5/aerosandbox/aerodynamics/casvlm1.py", line 1, in from .aerodynamics import * File "/Users/bradleyrelyea/Desktop/AeroSandbox-1.1.5/aerosandbox/aerodynamics/aerodynamics.py", line 1, in from ..geometry import * File "/Users/bradleyrelyea/Desktop/AeroSandbox-1.1.5/aerosandbox/geometry.py", line 1, in import plotly.express as px ModuleNotFoundError: No module named 'plotly'

Is your feature request related to a problem? I have realized that you update manually the version number. This could create problems and mismatches.

Describe the solution you'd like Include versioneer in the project.

It is a great tool, since when you haven't explicitly created a new tag, it indicates from the most recent tag you are working from, the number of commits you are ahead and the commit hash. When a clean tag is created, it's caught and correctly set.

I can implement this feature if you want to.

Nice project. I noticed your note re SI units

One final point to note: as we're all sensible and civilized human beings here, all inputs and outputs to AeroSandbox are expressed in base metric units (meters, Newtons, kilograms, etc.).

So may I take it that velocity is in m/s? If I wrote a pull request going through and annotating the docstrings to reflect would that be ok?

Bug Description

Running an inviscid analysis on a NACA 0012 airfoil at 0 degrees angle of attack produces non-zero lift coefficient.

Steps to Reproduce

from aerosandbox import Airfoil, AirfoilInviscid, OperatingPoint
a = AirfoilInviscid(
    airfoil=[
        Airfoil("naca0012")
            .repanel(50)
    ],
    op_point=OperatingPoint(
        velocity=1,
        alpha=0,
    )
)
print(f"CL: {a.Cl}")

CL: -0.17311351475463538

Expected Behavior

CL: 0

System Information

• Operating System: Windows 10
• Python Version: 3.9
• AeroSandbox Version: 3.0.13

when run the airfoil_xfoil_parallel.py file under spyder envirement, the out put are as follows:

Running XFoil sweeps on Airfoil sd7032... Traceback (most recent call last):

File "D:\PROGRAM\python\AeroSandbox\examples\geometry_engine\airfoil\airfoil_xfoil_parallel.py", line 8, in parallel=True

File "C:\ProgramData\Anaconda3\lib\site-packages\aerosandbox\geometry\airfoil.py", line 987, in get_xfoil_data pool = mp.Pool(mp.cpu_count())

File "C:\ProgramData\Anaconda3\lib\site-packages\multiprocess\context.py", line 119, in Pool context=self.get_context())

File "C:\ProgramData\Anaconda3\lib\site-packages\multiprocess\pool.py", line 176, in init self._repopulate_pool()

File "C:\ProgramData\Anaconda3\lib\site-packages\multiprocess\pool.py", line 241, in _repopulate_pool w.start()

File "C:\ProgramData\Anaconda3\lib\site-packages\multiprocess\process.py", line 112, in start self._popen = self._Popen(self)

File "C:\ProgramData\Anaconda3\lib\site-packages\multiprocess\context.py", line 322, in _Popen return Popen(process_obj)

File "C:\ProgramData\Anaconda3\lib\site-packages\multiprocess\popen_spawn_win32.py", line 46, in init prep_data = spawn.get_preparation_data(process_obj._name)

File "C:\ProgramData\Anaconda3\lib\site-packages\multiprocess\spawn.py", line 172, in get_preparation_data main_mod_name = getattr(main_module.spec, "name", None)

AttributeError: module 'main' has no attribute 'spec'

Hey Peter, I'm trying to use casll1 as a solver instead of optimizing and I'm performing an alpha sweep analysis on a conventional configuration using my own functions for the sectional Cl, Cd and Cm. These functions are just polynomial fits to data obtained from CFD analyses on the airfoil for the Reynolds and Mach number of interest. I'm defining the aircraft and running the alpha sweep the same way presented in the examples with the addition of the custom airfoil functions. However, depending on the operating point, the solver raises an error, which can be read using the cas.Opti().debug method:

sol
Opti(Opti {
  instance #0
  #variables: 2 (nx = 144)
  #parameters: 1 (np = 1)
  #constraints: 2 (ng = 144)
  CasADi solver allocated.
  CasADi solver was called: Infeasible_Problem_Detected
})

I played around with the solver settings and various paneling combinations, however, the issue persisted. Is this an issue with the casll1 solver or does it have to do with CasADI? Is there a way to use the casll1 solver without setting up an optimization environment?

I am also attaching the code I'm using along with a json file containing all the data required for the aircraft and operating point definition. aircraft_casll1.zip

Sorry for the long question. I really think what you are building here is great!

Hi Peter,

Great work! This is an awesome repo and I know it all takes work. I am curious about fuselages. In the examples, there is a definition for a fuselage (i.e. in the glider definition for example) but in the output display it is not shown? Is there a way to display a fuselage easily in the output? Is the fuselage not included in the aerodynamic analysis?

Thanks for your help!

Hi Peter,

I have been experimenting with your software and now I wanted to model control surfaces on a wing as well. The picture in the ReadMe shows a VLM simulation with an aileron deflection. I tried to reproduce it but can't make it work, the deflection never shows up. Are control surfaces currently not working because they are under a rework? If so, in what version do they work? I'm using aerosandbox 3.5.9

Thank you for your time. Best, Max

Hi Peter!

I want to use the panel method to evaluate the pressure field on the lower and the upper surfaces of an extruded NACA profile. The presence of the fuselage can be neglected and the profile considered as a cantilever beam fixed on one end. The resulting pressure field is then integrated to calculate the resultant at specific points.

Here is an example:

My question is, then, how can I use the AeroSandbox package to evaluate the pressure field? I saw this image (https://peterdsharpe.github.io/AeroSandbox/media/images/panel1_naca4412.png) on the package readme.md and I wanted to do the same. The problem is that I looked extensively at the package's code and tutorials and I didn't find any reference to the panel method. Is any sort of panel method implemented in your toolbox? Or I'm completely wrong and you calculated the pressure field in the image using the VLM?

Keep up with the wonderful work you're doing, the outcomes of AeroSandbox are really interesting.

Hi,

I am trying to use vortex lattice methods for optimal control problems. I successfully used the AeroBuildup module for optimizing a trajectory, but optimizing the design with this module doesn't make sense because my design isn't to adapted to it. When trying to switch to vortex lattice method with a number of variables > 1 using the following code:

import aerosandbox.numpy as np
import aerosandbox as asb

opti = asb.Opti()

n_vars = 2
alpha = opti.variable(n_vars=n_vars)
beta = np.linspace(0,2,n_vars)

vlm_results = asb.VortexLatticeMethod(
    airplane=airplane,
    op_point=asb.OperatingPoint(
        atmosphere=asb.Atmosphere(),
        alpha = alpha,
        beta = beta
    )
).run()

opti.subject_to([
    vlm_results["F_g"][1] = 100
])

sol = opti.solve()

I get this error:

Traceback (most recent call last):
  File "AeroSandbox/aerosandbox/aerodynamics/aero_3D/vortex_lattice_method.py", line 197, in run
    steady_freestream_velocity = self.op_point.compute_freestream_velocity_geometry_axes()  # Direction the wind is GOING TO, in geometry axes coordinates
  File "AeroSandbox/aerosandbox/performance/operating_point.py", line 235, in compute_freestream_velocity_geometry_axes
    return self.compute_freestream_direction_geometry_axes() * self.velocity
  File "AeroSandbox/aerosandbox/performance/operating_point.py", line 231, in compute_freestream_direction_geometry_axes
    return self.compute_rotation_matrix_wind_to_geometry() @ np.array([-1, 0, 0])
  File "AeroSandbox/aerosandbox/performance/operating_point.py", line 212, in compute_rotation_matrix_wind_to_geometry
    alpha_rotation = np.rotation_matrix_3D(
  File "AeroSandbox/aerosandbox/numpy/rotations.py", line 104, in rotation_matrix_3D
    return array(rot)
  File "/AeroSandbox/aerosandbox/numpy/array.py", line 31, in array
    return _cas.vertcat(
  File "/home/charles/miniconda3/envs/py39/lib/python3.9/site-packages/casadi/casadi.py", line 466, in vertcat
    def vertcat(*args): return _vertcat(args)
  File "/home/charles/miniconda3/envs/py39/lib/python3.9/site-packages/casadi/casadi.py", line 20204, in _vertcat
    return _casadi._vertcat(*args)
NotImplementedError: Wrong number or type of arguments for overloaded function '_vertcat'.
  Possible prototypes are:
    _vertcat([Sparsity])
    _vertcat([DM])
    _vertcat([SX])
    _vertcat([MX])
  You have: '(([MX|int],DM,[MX|int]))'

I guess this compute_rotation_matrix_wind_to_geometry does not support mixed types. Is it a feature that is planned to be available any time soon ?

Thank you

I have been working on geometry conversion from openvsp to aerosandbox and am creating the pull request for discussion.

I was thinking the workflow could be:

• create model in openvsp gui tool and save model
• make openvsp file available to a jupyter notebook running against a docker container.
• run geometry conversion inside notebook
• Use aerosandbox for further analysis and use interfaces to xfoil and avl.

Is there interest in this feature? Is this the correct folder for it?

Here is a test conversion of an openvsp model: (some small bugs still...)

Fuselage difference can be seen because openvsp allows curves between xsec while aerosandbox uses lines. If you are drawing your own model you can increase the number of xsec used. This model taken from openvsp hangar is using 2 fuselage to make the main body shape.

I also use scivm account so other pull request related to docker/jupyter is from me.