PROPAN - Potential Flow Code for Foils and Rotors: PROPAN is short for Propeller Panel Method. PROPAN is a panel code for the calculation of steady and unsteady potential flow around foils, open and ducted propellers, and wind and marine current turbines. PROPAN was developed by MARETEC (Marine and Environmental Technology Research Centre) at Instituto Superior Técnico (IST) which belongs to Lisbon University.

1. PROPAN
- Propeller Panel Code -
Instituto Superior Técnico,
Universidade de Lisboa, Portugal
21st January 2020 Instituto Superior Técnico 1

2. Outline
Theoretical Formulation
Current Features
IT Aspects
Pre/Post-Processing
Verification Studies
Applications
Main Publications
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3. Introduction:
PROPAN: Propeller Panel Code
Started to be developed at IST in 1996
Originally for potential flow calculations on marine propellers
www.researchgate.net/project/
PROPAN-potential-flow-code-for-foils-and-rotors
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4. Theoretical Formulation:
Assume incompressible, ideal (inviscid) fluid and irrotational flow
Fredholm integral equation for Morino formulation:
2πφ (p, t) =
RR
SB
h
G (p, q) ∂φ
∂nq
− φ (q, t) ∂G
∂nq
i
dS −
RR
SW
∆φ (q, t) ∂G
∂nq
dS
where G (p, q) = −1/R (p, q)
Surface discretisation: structured grid with quadrilateral panels
Integral equation solved by collocation method
Constant source and dipole distributions
Iterative pressure Kutta condition
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5. Current Features:
wings and rotors (open or inside a shroud)
conventional and quasi-orthogonal grids
steady and unsteady flows
empirical rigid wake model and wake alignment model
wetted flow, sheet partial (both face and back sides) and
super-cavitation (one side only) on the blades
leading-edge flow separation
post-processing 2d viscous corrections
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6. IT Aspects:
input/output in ASCII format
no GUI
visualisation with Tecplot
not parallelised
routines in Fortran90
Windows/Linux
no code version (svn/git)
no website, bug tracking system, forum, etc.
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7. Pre/Post-Processing:
Codes written in Fortran90
PROPANEL
Pre-Processor
PROPAN
Panel Method
PROPOST
Post-Processor
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8. Pre-Processing: PROPANEL
conventional and quasi-orthogonal grids: wings
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9. Pre-Processing: PROPANEL
conventional and quasi-orthogonal grids: propeller blades
X
Y
Z X
Y
Z
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10. Pre-Processing: PROPANEL
cylindrical and helical grids: ducts
X
Y
Z
X
Y
Z
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11. Pre-Processing: PROPANEL
hub grids
X
Y
Z
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12. Verification Studies: sphere
grid convergence of velocity potential (Baltazar, 2005)
Sphere Grid L2 Error Norm L∞ Error Norm
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13. Verification Studies: ellipsoids
Computers & Fluids, 35 (2006)
Conventional Grid (CG)
Orthogonal Grid (OG)
Grid Convergence of Velocity Potential
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14. Applications:
wings
marine propellers
marine current turbines
wind turbines
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15. Applications: wings
elliptical wing, NACA0015, α = 8o
X
Y Z
s/c
0.0 0.2 0.4 0.6 0.8 1.0
-1.0
-0.5
0.0
0.5
1.0
1.5
2.0
Present Method
Suction Side - Experiments
Pressure Side - Experiments
y/S=0.80
-C
p
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16. Applications: wings
rigid and aligned wakes
X
Y
Z
X
Y
Z
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17. Applications: wings
delta wing
76 deg. Delta Wing Empirical Wake Geometry
X
Y
Z
ri
0
ri
1
θi
0
θi
1
(yi
VF,zi
VF)
z
y
SB
SLW
Feeding-
Sheet
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18. Applications: wings
76 deg. delta wing at 20 deg. incidence
y/S
0.0 0.2 0.4 0.6 0.8 1.0
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
x/C0=0.15
x/C0=0.35
x/C0=0.55
x/C0=0.75
x/C0
=0.95
-Cp
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19. Applications: wings
76 deg. delta wing at 20 deg. incidence - pressure distribution
y/S
0.0 0.2 0.4 0.6 0.8 1.0
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
x/C0
=0.05
Hoeijmakers (1989)
-C
p
y/S
0.0 0.2 0.4 0.6 0.8 1.0
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
x/C0
=0.35
Hoeijmakers (1989)
-C
p
y/S
0.0 0.2 0.4 0.6 0.8 1.0
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
x/C0
=0.65
Hoeijmakers (1989)
-C
p
y/S
0.0 0.2 0.4 0.6 0.8 1.0
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
x/C0
=0.95
Hoeijmakers (1989)
-C
p
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20. Applications: marine propellers
open propellers
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21. Applications: marine propellers
rigid and aligned wakes
X
Y
Z
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22. Applications: marine propellers
cavitation analysis
0.0051
0.0045
0.0040
0.0034
0.0028
0.0023
0.0017
0.0011
0.0006
0.0000
η/R
J=0.6, σn
=1.2
0.0128
0.0114
0.0100
0.0086
0.0071
0.0057
0.0043
0.0029
0.0014
0.0000
η/R
J=0.4, σn
=2.2
0.0201
0.0177
0.0153
0.0128
0.0104
0.0080
0.0055
0.0031
0.0007
0.0001
0.0000
η/R
J=0.4, σn
=1.5
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23. Applications: marine propellers
performance behind wake field
z0
-1.0 -0.5 0.0 0.5 1.0
-1.0
-0.5
0.0
0.5
1.0
Vxxxxx: 0.15 0.26 0.37 0.48 0.59 0.70 0.81 0.93
y
0
Uey
2
+Uez
2
=VS
2
Uex /VS:
θ [º]
0 60 120 180 240 300 360
0.00
0.03
0.06
0.09
0.12
KT
Panel Method
10KQ
Panel Method
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24. Applications: marine propellers
ducted propellers
X
Y
Z
J
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
-0.1
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
Experiments: Re=ΩR/ν=1.23×106
Rigid Wake Model
Wake Alignment Model (WAM)
WAM with Duct Boundary Layer Correction
Closed Gap Model
KT
10KQ
KTD
P
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25. Applications: marine propellers
leading-edge vortex sheet separation modeling
s/c
-C
p
0.0 0.2 0.4 0.6 0.8 1.0
-0.5
0.0
0.5
1.0
1.5
2.0
r/R=0.75
r/R=0.90
r/R=0.95
r/R=0.99
attached flow
s/c
0.0 0.2 0.4 0.6 0.8 1.0
-1.0
-0.5
0.0
0.5
1.0
r/R=0.75
r/R=0.90
r/R=0.95
r/R=0.99
-C
p
with leading edge vortex separation
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26. Applications: marine current turbines
performance characteristics in uniform flow
TSR
2 4 6 8 10
0.0
0.2
0.4
0.6
0.8
1.0
1.2
5º - Experiments (Bahaj et al, 2007)
10º
12º
15º
5º - Present Method
10º
12º
15º
C
T
Axial Force Coefficient
TSR
2 4 6 8 10
0.0
0.2
0.4
0.6
0.8
5º - Experiments (Bahaj et al, 2007)
10º
12º
15º
5º - Present Method
10º
12º
15º
C
P
Power Coefficient
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27. Applications: marine current turbines
cavitation analysis
X
Z
Y
0.0027
0.0024
0.0021
0.0018
0.0015
0.0012
0.0009
0.0006
0.0003
0.0000
η/R
Pressure
Side
X
Y
Z
0.0009
0.0008
0.0007
0.0006
0.0005
0.0004
0.0003
0.0002
0.0001
0.0000
η/R
Suction
Side
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28. Applications: marine current turbines
cavitation analysis
X
Y
Z 0.0045
0.0040
0.0035
0.0030
0.0025
0.0020
0.0015
0.0010
0.0005
0.0000
η/R
Taken from Bahaj et al. (2007).
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29. Applications: marine current turbine
performance in tidal profile
U/U
y
0
/d
0.0 0.2 0.4 0.6 0.8 1.0
0.0
0.2
0.4
0.6
0.8
1.0
Tidal Velocity Profile
U(y0)=U(y0/d)
1/7
--
Velocity profile across the
marine current turbine,
based on a 10 m radius turbine
in a 30 m deep sea and a
tidal speed of 2 m/s
Set Angle 5º, TSR=6
θ0 [º]
0 120 240 360
0.12
0.16
0.20
0.24
0.28
Blade A
Blade B
Blade C
Axial Force and Power Fluctuations
CT
CP
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30. Applications: marine current turbines
unsteady cavitation in tidal profile
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31. Applications: marine current turbines
yawed inflow conditions
TSR
2 4 6 8 10
0.0
0.2
0.4
0.6
0.8
1.0
1.2
Experiments (Bahaj et al., 2007)
Panel Method
Panel Method with Drag Corrections
Panel Method with Viscous Corrections
C
T
15º Yaw Angle
TSR
2 4 6 8 10
0.0
0.2
0.4
0.6
0.8
1.0
1.2
Experiments (Bahaj et al., 2007)
Panel Method
Panel Method with Drag Corrections
Panel Method with Viscous Corrections
C
T
30º Yaw Angle
TSR
2 4 6 8 10
0.0
0.2
0.4
0.6
0.8
Experiments (Bahaj et al., 2007)
Panel Method
Panel Method with Drag Corrections
Panel Method with Viscous Corrections
C
P
15º Yaw Angle
TSR
2 4 6 8 10
0.0
0.2
0.4
0.6
0.8
Experiments (Bahaj et al., 2007)
Panel Method
Panel Method with Drag Corrections
Panel Method with Viscous Corrections
C
P
30º Yaw Angle
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32. Applications: wind turbines
performance prediction
TSR=5.42; CP
=0.326 (Num.); CP
=0.358 (Exp.)
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33. Applications: wind turbines
performance prediction
s/c
-C
p
0.0 0.2 0.4 0.6 0.8 1.0
-1.0
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
Experiments
Panel Method
r/R=0.30
s/c
-C
p
0.0 0.2 0.4 0.6 0.8 1.0
-1.0
0.0
1.0
2.0
3.0
4.0
Experiments
Panel Method
r/R=0.47
s/c
-C
p
0.0 0.2 0.4 0.6 0.8 1.0
-1.0
0.0
1.0
2.0
3.0
4.0
Experiments
Panel Method
r/R=0.63
s/c
-C
p
0.0 0.2 0.4 0.6 0.8 1.0
-1.0
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
Experiments
Panel Method
r/R=0.80
s/c
-C
p
0.0 0.2 0.4 0.6 0.8 1.0
-1.0
-0.5
0.0
0.5
1.0
1.5
Experiments
Panel Method
r/R=0.95
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34. Applications: wind turbines
performance prediction
TSR
C
P
0 1 2 3 4 5 6
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0.5
Experimental
BEM Goldstein
BEM
Lifting Line
Panel Method
TSR
C
T
0 1 2 3 4 5 6
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0.5
0.55
0.6
BEM Goldstein
BEM
Lifting Line
Panel Method
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35. Main Publications:
• J. Baltazar. “Estudo Numérico do Escoamento Potencial na Extremidade de Asas Elı́pticas com um Método de
Elementos de Fronteira.” Master’s Thesis, IST, May 2002. (in Portuguese)
• J. Baltazar. “A Higher Order Potential Based BEM for Three-Dimensional Flows.” Technical Report
POSI-SFRH/BD/14334/2003, April 2005.
• J. Baltazar. “On the Modelling of the Potential Flow About Wings and Marine Propellers Using a Boundary Element
Method.” Ph.D. Thesis, IST, September 2008.
• J. Baltazar. “Leading-Edge Vortex Flow Modelling Around Delta Wings Using a Boundary Element Method.” In
Proceedings of the III Conferência Nacional em Mecânica de Fluidos, Termodinâmica e Energia, September 2009.
• J. Baltazar, L. Eça. “Generación de Mallas Estructurada en Superficie.” Información Tecnológica 17(3), 107-116,
2005. (in Spanish)
• J. Baltazar, L. Eça. “A Surface Grid Generation Technique for Practical Applications of Boundary Element Methods.”
In Proceedings of the Conferência Nacional de Métodos Numéricos em Mecânica dos Fluidos e Termodinâmica, June
2006.
• J. Baltazar, J.A.C. Falcão de Campos. “A Study on the Modeling of Marine Propeller Tip Flows Using BEM.” In
Proceedings of the Congreso de Métodos Numéricos en Ingenierı́a, July 2005.
• J. Baltazar, J.A.C. Falcão de Campos. “Unsteady Potential Flow Calculations of Marine Propellers Using BEM.” In
Proceedings of the Conferência Nacional de Métodos Numéricos em Mecânica dos Fluidos e Termodinâmica, 2006.
• J. Baltazar, J.A.C. Falcão de Campos. “Hydrodynamic Analysis of a Horizontal Axis Marine Current Turbine With a
Boundary Element Method.” In Proceedings of the 27th International Conference on Offshore Mechanics and Arctic
Engineering, June 2008.
• J. Baltazar, J.A.C. Falcão de Campos. “A Boundary Element Method for the Unsteady Hydrodynamic Analysis of
Marine Current Turbines.” In Proceedings of the 2nd International Conference on Ocean Energy, October 2008.
• J. Baltazar, J.A.C. Falcão de Campos. “Unsteady Analysis of a Horizontal Axis Marine Current Turbine in Yawed Inflow
Conditions With a Panel Method.” In Proceedings of the 1st International Symposium on Marine Propulsors, 2009.
• J. Baltazar, J.A.C. Falcão de Campos. “On the Modelling of the Flow in Ducted Propellers With a Panel Method.” In
Proceedings of the 1st International Symposium on Marine Propulsors, June 2009.
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36. Main Publications:
• J. Baltazar, J.A.C. Falcão de Campos. “A Numerical Study on the Iterative Techniques to Solve Partial Cavitation on
Marine Propellers Using BEM.” In Proceedings of the International Conference on Computational Methods in Marine
Engineering, June 2009.
• J. Baltazar, J.A.C. Falcão de Campos. “An Iteratively Coupled Solution of the Cavitating Flow on Marine Propellers
Using BEM.” Journal of Hydrodynamics 22(5) supplement 1, 838-843, 2010.
• J. Baltazar, J.A.C. Falcão de Campos. “Hydrodynamic Analysis of a Horizontal Axis Marine Current Turbine With a
Boundary Element Method.” Journal of Offshore Mechanics and Arctic Engineering, Vol. 133, November 2011.
• J. Baltazar, J.A.C. Falcão de Campos. “Prediction of Sheet Cavitation on Marine Current Turbines With a Boundary
Element Method.” In Proceedings of the ASME 31st International Conference on Ocean, Offshore and Arctic
Engineering, OMAE, 2012.
• J. Baltazar, J.A.C. Falcão de Campos. “An Iteratively Coupled Solution Method for Partial and Super-Cavitation
Prediction on Marine Propellers Using BEM.” In Proceedings of the 10th International Conference on Hydrodynamics,
October 2012.
• J. Baltazar, J.A.C. Falcão de Campos. “Prediction of Unsteady Sheet Cavitation on Marine Current Turbines With a
Boundary Element Method.” In Proceedings of the 6th International Conference on Mechanics and Materials in
Design, July 2015.
• J. Baltazar, J.A.C. Falcão de Campos. “A Comparison of Panel Method and RANS Calculations for a Horizontal Axis
Marine Current Turbine.” In book: CFD for Wind and Tidal Offshore Turbines. Publisher: Springer International
Publishing. Editors: Esteban Ferrer, Adeline Montlaur, 117-128, 2015.
• J. Baltazar, J.A.C. Falcão de Campos. “An Iteratively Coupled Solution Method for Unsteady Sheet Cavitation
Prediction on Marine Propellers Using BEM.” In Proceedings of the 12th International Conference on Hydrodynamics,
2016.
• J. Baltazar, J.A.C. Falcão de Campos. “Potential Flow Modelling of Ducted Propellers With Blunt Trailing Edge Duct
Using a Panel Method.” In Proceedings of the 6th International Symposium on Marine Propulsors, May 2019.
• J. Baltazar, J.A.C. Falcão de Campos, J. Bosschers. “A Study on the Accuracy of Low and Higher Order BEM in
Three-Dimensional Potential Flows Past Ellipsoids.” In Proceedings of the 5th International Conference on Boundary
Element Techniques, July 2004.
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37. Main Publications:
• J. Baltazar, J.A.C. Falcão de Campos, J. Bosschers. “Open-Water Thrust and Torque Predictions of a Ducted
Propeller System with a Panel Method.” International Journal of Rotating Machinery, Article ID 474785, 2012.
• J. Baltazar, J.A.C. Falcão de Campos, J. Bosschers. “Potential Flow Modelling of Ducted Propellers With a Panel
Method.” In Proceedings of the 4th International Symposium on Marine Propulsors, June 2015.
• J. Baltazar, J.A.C. Falcão de Campos, J. Bosschers, D. Rijpkema. “Recent Developments in Computational Methods
for the Analysis of Ducted Propellers in Open Water.” Journal of Ship Research 63(4), 219-234, December 2019.
• J. Baltazar, D. Melo, D. Rijpkema. “Analysis of the Blade Boundary-Layer Flow of a Marine Propeller With RANSE.”
In Proceedings of the VIII International Conference on Computational Methods in Marine Engineering, 2019.
• J. Baltazar, D. Rijpkema, J.A.C. Falcão de Campos, J. Bosschers. “A Comparison of Panel Method and RANS
Calculations for a Ducted Propeller System in Open-Water.” In Proceedings of the 3rd International Symposium on
Marine Propulsors, May 2013.
• J. Baltazar, D. Rijpkema, J.A.C. Falcão de Campos, J. Bosschers. “Prediction of the Open-Water Performance of
Ducted Propellers With a Panel Method.” In Proceedings of the 5th International Symposium on Marine Propulsors,
June 2017.
• J. Baltazar, D. Rijpkema, J.A.C. Falcão de Campos, J. Bosschers. “Prediction of the Open-Water Performance of
Ducted Propellers with a Panel Method. ” Journal of Marine Science and Engineering 6(1), 2018.
• J.A.C. Falcão de Campos, P.J.A. Ferreira de Sousa, J. Bosschers. “A Verification Study on Low-Order
Three-Dimensional Potential-Based Panel Codes.” Computers & Fluids 35, 61-73, 2006.
• T. Clara, J.A.C. Falcão de Campos, J. Baltazar. “Added Mass Effects on the Natural Frequencies of Marine Current
Turbine Blades.” In Proceedings of the 6th International Conference on Mechanics and Materials in Design, July 2015.
• R. Duarte. “Estudos Sobre um Método de Elementos de Fronteira Para o Cálculo do Escoamento Potencial
Estacionário em Hélices Propulsores Marı́timos.” Master’s Thesis, IST, December 1997. (in Portuguese)
• F. Hogan. “Análise do Desempenho Aerodinâmico da Turbina Eólica NREL com um Método de Elementos de
Fronteira.” Master’s Thesis, IST, October 2010. (in Portuguese)
• P. Ponte. “Effect of the Duct Trailing Edge Geometry on the Calculation of a Ducted Propeller With a Boundary
Element Method.” Master’s Thesis, IST, November 2011.
• E. Quarona. “Design Loading Optimization of a Horizontal Axis Turbine with Lifting Line and Panel Method.”
Master’s Thesis, IST, October 2019.
21st January 2020 Instituto Superior Técnico 37