Sphere Fuse Quad panel analysis failure

Kevin UlmerKevin Ulmer asked 4 years ago

I have tried to reproduce the example from the Triangle Based Panel Methods video, but the Uniform Density Quad Panel analysis fails. I used the Plane Editor Insert – Testing – Insert Sphere Fuse to create the sphere. Both the Uniform Density Triangular Panels and Linear Density Triangle Panels analyses worked fine. I’ve attached the log file from the Quad Panels analysis and not that it “Could not allocate memory for panel arrays”. Perhaps I missed a setting? This is on a Mac.
flow5 v7.01_beta_12
Fri Aug 14 13:53:47 2020
Launching analysis
Initializing task
Sphere fuse
T1-20.0 m/s-Quads-ThickSurf
Checking plane and polar data
…done
Initializing the Quad analysis
T1-20.0 m/s-Quads-ThickSurf
Type 1 – Fixed speed polar
Density = 1.225kg/m3
Viscosity = 1.5e-05m²/s
RFF = 10.0
Core radius = 1e-05m
Running in multi-threaded mode
Linear system calculations in floating point double precision
Using S. Nintcheu-Fata’s method for off-plane integrals
Allocating 0.00Mb for the influence matrix
Could not allocate memory for panel arrays
Allocating result arrays
Locking objects
Setting inertia
Mass= 0.000 kg
___Center of Gravity Position – Body axis____
CoG_x= 0.0000 m
CoG_y= 0.0000 m
CoG_z= 0.0000 m
___Inertia – Body Axis – CoG Origin____
Ibxx= 0 kg.m²
Ibyy= 0 kg.m²
Ibzz= 0 kg.m²
Ibxz= 0 kg.m²
Solving the problem…
Making the unit RHS vectors…
Making the influence matrix…
Adding the wake’s contributions…
Time to make the wake contribution: 0.00 s
LAPACK – LU factorization…
Factorizing LU…
Time to solve the linear system: 0.000 s
Making the unit local panel velocities …
Computing on-body pressure coefficients…
Creating source strengths…
Calculating doublet strengths…
Calculating cross-flow forces…
Calculating far-field induced drag…
Computing Plane for alpha=0.00° beta=0.00°
Computing Plane for alpha=1.00° beta=0.00°
Computing Plane for alpha=2.00° beta=0.00°
Computing Plane for alpha=3.00° beta=0.00°
Computing Plane for alpha=4.00° beta=0.00°
Computing Plane for alpha=5.00° beta=0.00°
Computing Plane for alpha=6.00° beta=0.00°
Computing Plane for alpha=7.00° beta=0.00°
Computing Plane for alpha=8.00° beta=0.00°
Computing Plane for alpha=9.00° beta=0.00°
Computing Plane for alpha=10.00° beta=0.00°

Panel Analysis completed successfully
Cleaning up
Analysis ended Fri Aug 14 13:53:47 2020
Elapsed: 0.33 s

1 Answers
André Deperroistechwinder Staff answered 4 years ago

This is because the function used to build the sphere only creates a triangular mesh and not a quad mesh.
Internally the sphere is mapped to an STL type fuselage – just for testing purposes.

Kevin UlmerKevin Ulmer replied 4 years ago

So how did you generate the quad-paneled sphere in the video?

André Deperroistechwinder Staff replied 4 years ago

I built it manually.