SW2D-Lemon: A New Software for Upscaled Shallow Water Modeling

J. G. Caldas S eins aesse , e al., Ad ances in hyd oin o ma ics, 10.1007/978-981-19-1600-7_2
SW2D-LEMON: A NEW SOFTWARE
FOR UPSCALED SHALLOW WATER MODELING
Joao Guilhe me Caldas S eins aesse
In ia, IMAG, Uni Mon pellie , CNRS, Mon pellie , F ance
Ca ole Delenne
Uni Mon pellie , HSM, CNRS, IRD, In ia, Mon pellie , F ance
Pascal Finaud-Guyo
Uni Mon pellie , HSM, CNRS, IRD, In ia, Mon pellie , F ance
Vincen Guino
Uni Mon pellie , HSM, CNRS, IRD, In ia, Mon pellie , F ance
Joseph Luis Kahn Casapia
In ia, IMAG, Uni Mon pellie , CNRS, Mon pellie , F ance
An oine Rousseau
In ia, IMAG, Uni Mon pellie , CNRS, Mon pellie , F ance
ABSTRACT
We p esen a new mul i-OS pla o m named SW2D-LEMON (SW2D o Shallow Wa e 2D) de eloped by he
LEMON esea ch eam in Mon pellie . SW2D-LEMON is a mul i-model so wa e ocusing on shallow wa e -
based models. I includes an unp eceden ed collec ion o upscaled (po osi y) models used o shallow
wa e equa ions and anspo - eac ion p ocesses. Po osi y models a e ob ained by a e aging he wo-
dimensional shallow wa e equa ions o e la ge a eas con aining bo h a wa e and a solid phase. The size o
a compu a ional cell can be inc eased by a ac o 10 o 50 compa ed o a 2D shallow wa e model, wi h CPU
imes educed by 2 o 3 o de s o magni ude. Applica ions include u ban lood simula ions as well as lows
o e complex opog aphy. Besides he s anda d shallow wa e equa ions ( he de aul model), se e al
po osi y models a e included in he pla o m: (i) Single Po osi y, (ii) Dual In eg al Po osi y, and o he s a e
cu en ly unde de elopmen such as (iii) Dep h-dependen Po osi y model. Va ious low p ocesses
( ic ion, head losses, wind, momen um di usion, p ecipi a ion/in il a ion) can be included in a modula
way by ac i a ing speci ic execu ion lags. We ecall he e he go e ning equa ions as well as nume ical
aspec s and p esen he so wa e ea u es. Se e al examples a e p esen ed o illus a e he po en ial o
SW2D.
1. INTRODUCTION
In his pape , we p esen a new mul i-OS pla o m named SW2D-LEMON (SW2D o Shallow Wa e 2D)
de eloped by he LEMON esea ch eam in Mon pellie .
Simula ing u ban loods and ee su ace lows in we lands equi es conside able compu a ional powe . Two-
dimensional shallow wa e models a e needed. Cap u ing he ele an hyd aulic de ail o en equi es
compu a ional cell sizes smalle han one me e . Fo ins ance, meshing a comple e u ban a ea wi h a
su icien accu acy would equi e 106 o 108 cells, and simula ing one second o en equi es se e al CPU
seconds. This makes he use o such model o c isis managemen impossible. Simila issues a ise when
modelling we lands and coas al lagoons, whe e la ge a eas a e o en connec ed by an o e whelming numbe
o na ow channels, obs uc ed by ege a ion and a s ongly a iable ba hyme y. Desc ibing such channels
wi h he le el o de ail equi ed in a 2D model is imp ac icable. A new gene a ion o models o e coming his
issue has eme ged o e he las 20 yea s: po osi y-based shallow wa e models. They a e ob ained by
a e aging he wo-dimensional shallow wa e equa ions o e la ge a eas con aining bo h wa e and a solid
phase [8]. The size o a compu a ional cell can be inc eased by a ac o 10 o 50 compa ed o a 2D shallow
wa e model, wi h CPU imes educed by 2 o 3 o de s o magni ude. Resea ch on po osi y-based shallow
wa e models has accele a ed o e he pas 15 yea s, wi h signi ican con ibu ions led by V. Guino and ou
esea ch eam [1], [2], [3], [4], [13], [15], [20].
SW2D-LEMON is he so wa e con inua ion o his 15 yea s esea ch p oduc ion. I ollows he o iginal
esea ch code i s de eloped by V. Guino in Fo an 90. SW2D-LEMON is mul i-pla o m (Linux, MacOS,
Windows) and includes a con enien g aphical use in e ace (GUI) oge he wi h an unp eceden ed
collec ion o upscaled (po osi y) models used o shallow wa e equa ions and anspo - eac ion p ocesses.
Applica ions include u ban lood simula ions as well as lows o e complex opog aphy wi h uns uc u ed
g ids. Besides he s anda d shallow wa e equa ions ( he de aul model), se e al po osi y models a e al eady
included in he pla o m such as Single Po osi y and Dual In eg al Po osi y. Va ious low p ocesses ( ic ion,
head losses, wind, momen um di usion, p ecipi a ion/in il a ion) can be included in a modula way by
ac i a ing speci ic execu ion lags.
The pape is o ganized as ollows: in Sec ion 2, we ecall he adi ional shallow wa e equa ions as ob ained
by Sain -Venan , be o e de ining he no ion o po osi y, p esen ing he single and dual po osi y models and
hen he (s anda d) ea u es o he nume ical schemes used in he code. Sec ion 3 desc ibes he SW2D-Lemon
wo k low by p esen ing he inpu s and ou pu s as well as he di e en op ions a ailable o he modele .
Sec ion 4 p esen s he h ee di e en licenses p o ided o he so wa e be o e illus a ing he ins alla ion
p ocess unde Windows. Finally, we end his a icle wi h a p esen a ion o he es cases ha a e p o ided in
e sion 1.0 o he code, ha will be made a ailable o he Poly ech'Mon pellie enginee ing school om
Sep embe 2021.
Fo he sake o simplici y, he SW2D ac onym will hold o SW2D-Lemon he ea e . Fo mo e in o ma ion
on SW2D-LEMON, please isi h p://sw2d.in ia.
2. MODELLING
2.1 Equa ions and sou ce e ms
The cu en e sion o he SW2D simula ion engine inco po a es he Shallow Wa e Equa ions (SWEs), he
Single Po osi y (SP) [1] and he Dual In eg al Po osi y (DIP) [2] models. O he models published by membe s
o he LEMON eam, such as he Mul iple Po osi y (MP) [3] and Dep h-Dependen Po osi y (DDP) [4] models,
a e cu en ly unde in eg a ion and es ing and should be eleased soon. The go e ning equa ions o hese
h ee models can be w i en in he o m
𝜕!𝐮+𝐌%∇.𝐅=𝐬
(1)
whe e is ime, u and s a e espec i ely he conse ed a iable and sou ce e m ec o s, and F and M a e espec i ely
he lux and ine ia enso s.
The SWE model, an ex ension o Sain Venan ’s one-dimensional equa ions [5], uses he ollowing de ini ions o u, s, F
and M:
𝐮=
+
ℎ
ℎ𝑢
ℎ𝑣
/
,𝐬=
1
𝑅−𝐼
𝑔ℎ
6
𝑆",$ −𝑆%,$
8
−𝐼𝑢+𝑊$
𝑔ℎ
6
𝑆",& −𝑆%,&
8
−𝐼𝑣+𝑊&
:
%%
(2a)
𝐅=
1
ℎ𝑢 ℎ𝑣
ℎ𝑢'+𝑔ℎ'/2 ℎ𝑢𝑣
ℎ𝑢𝑣 ℎ𝑣'+𝑔ℎ'/2
:
,𝐌=𝐈𝐝
(2b)
whe e
𝑔
is he g a i a ional accele a ion,
ℎ
is he wa e dep h,
𝑢
and
𝑣
a e espec i ely he
𝑥 −
and
𝑦 −
componen s o he low eloci y,
𝐼
is he in il a ion a e,
𝑅
is he ain all in ensi y,
𝑆!,#
and
𝑆$,#
(
𝑋 =
𝑥, 𝑦
) a e espec i ely he bo om and ic ion slopes in he
𝑋 −
di ec ion, and
𝑊
#
(
𝑋 = 𝑥, 𝑦
) is he wind d ag
speci ic o ce in he
𝑋 −
di ec ion. An eigen alue analysis o his model is p o ided in [6]. The wind d ag o ce
is compu ed using Smi h and Banke’s model [7].
The SP model was i s in oduced in a dep h-dependen e sion [7] o model he e ec s o subg id scale
opog aphy. A dep h-independen e sion o he modelling o u ban loods was p esen ed in non-
conse a ion o m [8] and la e adap ed o shock-cap u ing ini e olume me hods and discon inuous u ban
ea u e p ope ies [1]. In his model, u, s, F and M a e de ined as
𝐮=𝜙
+
ℎ
ℎ𝑢
ℎ𝑣
/
,𝐬=
1
𝑅−𝜙𝐼
𝜙𝑔ℎ
6
𝑆",$ −𝑆%,$
8
+𝑔ℎ𝜕$𝜙−𝜙𝐼𝑢+𝜙𝑊$
𝜙𝑔ℎ
6
𝑆",& −𝑆%,&
8
+𝑔ℎ𝜕&𝜙−𝜙𝐼𝑣+𝜙𝑊&
:
%%
(2a)
𝐅=ϕ
1
ℎ𝑢 ℎ𝑣
ℎ𝑢'+𝑔ℎ'/2 ℎ𝑢𝑣
ℎ𝑢𝑣 ℎ𝑣'+𝑔ℎ'/2
:
,𝐌=𝐈𝐝
(2b)
whe e
𝜙
is he plan iew ac ion o space a ailable o wa e . Po osi y models a e de i ed om he SWEs (1,
2a-b) by pe o ming a olume a e aging [9] o e a con ol olume con aining a wa e and a solid phase. The
unde lying assump ion o he SP model is ha he s a is ics o he wa e -solid pa i ion con e ge o he same
alues when compu ed o e a ho izon al 2D domain and o e i s bounda y. As no iced in [10], his is
equi alen o assuming he exis ence o he Re e ence Elemen a y Volume (REV) [11], an assump ion ha
does no hold in ypical u ban a eas [3].
The DIP model [2] was in oduced as an imp o ed e sion o he In eg al Po osi y model [10]. I uses he
ollowing de ini ions o he e ms in Equa ion (1)
𝐮=𝜙(
+
ℎ
ℎ𝑢
ℎ𝑣
/
,𝐬=
1
𝑅−𝜙(𝐼
𝜙(𝑔ℎ
6
𝑆",$ −𝑆%,$
8
+𝑔ℎ𝜕$
(
𝜙)−𝜙(
)
−𝜙(𝐼𝑢+𝜙(𝑊$
𝜙(𝑔ℎ
6
𝑆",& −𝑆%,&
8
+𝑔ℎ𝜕&
(
𝜙)−𝜙(
)
−𝜙(𝐼𝑣+𝜙(𝑊&
:
%%
(3a)
𝐅=
⎣
⎢
⎢
⎢
⎡
𝜙(ℎ𝑢 𝜙(ℎ𝑣
*!
"
*#ℎ𝑢'+𝜙(𝑔ℎ'/2 *!
"
*#ℎ𝑢𝑣
*!
"
*#ℎ𝑢𝑣 *!
"
*#ℎ𝑣'+𝜙(𝑔ℎ'/2
⎦
⎥
⎥
⎥
⎤
,𝐌=
I
1 0
0 𝐃
M
𝐈𝐝
(3b)
𝐃=𝜖𝐑
P
𝜇+0
0 𝜇'
R
𝐑,+
,
𝜖=
S
1i %𝜕!ℎ>0
0i %𝜕!ℎ≤0
(3c)
whe e
𝜙%
and
𝜙&
a e espec i ely connec i i y and s o age po osi ies,
𝜇'3(𝑘 = 1,2)
is a momen um
dissipa ion coe icien (be ween 0 and 1) in he k h p incipal di ec ion, and R is he o a ion ma ix ha
ans o ms he x-di ec ion in o he i s p incipal di ec ion o D. The pu pose o he dissipa ion enso D is o
model he momen um dissipa ion a ising om he mul iple wa e e lec ions agains obs acles on he subg id
scale. This e m is ac i e only in he p esence o posi i e wa es, hence he
𝜖
swi ch (
𝜖 = 03o 3𝜖 = 1)
in Eq.
(3c). In con as wi h a classical sou ce e m in Eq. (1), he ine ia-modi ying enso M p ese es he sel -
simila p ope ies o he solu ion when Riemann p oblems a e deal wi h. This sel -simila i y p ope y was
iden i ied in [3], e i ied in [2], [4] and con i med in [12] by nume ical expe imen s. So a , no model has been
p oposed o he dissipa ion coe icien s
𝜇'
as unc ions o he hyd aulic condi ions and u ban geome y, and
he momen um dissipa ion enso D mus be calib a ed.
Fo all h ee models (1), (2) and (3), a bi a y ini ial condi ions may be p o ided. The s anda d ( ime-
dependen ) bounda y condi ion ypes handled by he models a e he ollowing:
– p esc ibed uni discha ge (in lowing o ou lowing),
– p esc ibed wa e dep h,
– p esc ibed ee su ace ele a ion,
– p esc ibed F oude numbe .
In all ou cases, i he wa e is lowing in o he domain, he low eloci y ec o is assumed no mal o he
bounda y. I he wa e is lowing ou o he domain, he la e al componen o he momen um is ad ec ed
wi h he low. An impe ious bounda y is conside ed as a pa icula case o a p esc ibed uni discha ge
bounda y, wi h he no mal discha ge se o ze o.
2.2 Nume ical aspec s
Equa ion (1) is sol ed nume ically using a ini e olume app oach on uns uc u ed g ids. Explici , Goduno -
ype shock-cap u ing me hods a e used o he solu ion o he hype bolic pa . The algo i hm is designed so
as o allow o elemen s wi h an a bi a y numbe o edges. The e o e, he mesh may be a mix u e o
iangula , quad angula o any ype o polygonal elemen s. Besides, he cells a e no equi ed o be con ex.
The solu ion p ocedu e in ol es a i s -o de ime spli ing [13]. Wi hin a compu a ional ime s ep, he
sequence is he same o all models:
1) Hype bolic pa
1.1) De e mine he maximum pe missible ime s ep based on CFL equi emen s o solu ion s abili y on
a bi a y-shaped g ids [14].
1.2) Recons uc he low a iables in case a highe -o de econs uc ion is used (MUSCL-EVR scheme
[15][14]).
1.3) Compu e he luxes and he sou ce e ms induced by po osi y g adien s and opog aphy g adien s
ac oss he in e aces (including bounda y in e aces) be ween he compu a ional cells using
app oxima e, HLLC- ype [15] [16] Riemann sol e s. In o de o speed up he compu a ional p ocess,
he use is allowed o speci y a h eshold wa e dep h. When he wa e in wo neighbou ing cells is
smalle han his h eshold, he wo cells a e assumed d y and ze o luxes a e se au oma ically
ac oss he in e ace. The de ails o he Riemann sol e s used can be ound in he e e ences o he
SP and DIP models [1] [2].
1.4) Ca y ou a mass and momen um balance o e he non-d y cells.
1.5) Apply he momen um dissipa ion enso D o he cells whe e he wa e le el has been iden i ied as
ising as a esul o S ep 1.4.
1.6) Re ise he balance using a di e gence co ec ion p ocedu e in case nega i e wa e dep hs a e
ob ained. Two op ions a e a ailable when he wa e dep h becomes nega i e wi hin a gi en cell :
(i) all he luxes ac oss he in e aces o he cell unde conce n a e mul iplied by he same ac o so
as o ob ain a ze o wa e dep h, o (ii) he compu a ional ime s ep is dec eased o he maximum
possible alue ha yields a ze o wa e dep h.
2) Compu e he e ec o sou ce e ms. All sou ce e ms a e local unc ions o he a e age low a iables
wi hin a gi en compu a ional cell, which in ol es sol ing only local, i s -o de o dina y di e en ial
equa ions wi h espec o ime wi hin each cell. The con ibu ions o he a ious sou ce e ms a e
compu ed sequen ially
2.1) Compu e he e ec s o ic ion. The use can speci y he ic ion model o mula ion (Manning,
S ickle , Chezy, e c.)
2.2) Compu e he e ec s o p ecipi a ion/in il a ion
2.3) Compu e he e ec s o wind shea s ess
I is wo h no ing ha he MUSCL-EVR app oach [14] used in he hype bolic pa is signi ican ly
compu a ionally cheape han he classical second-o de ime s epping MUSCL app oach (also called MUSCL-
Hancock [18]), because i in ol es a single s ep ime in eg a ion and he econs uc ion o a single a iable
( he ee su ace ele a ion) ins ead o h ee in he usual p ocedu e.
3. SOFTWARE FEATURES
SW2D is mul i-pla o m and uns on Linux, MacOS and Windows. I includes all models p esen ed in Sec ion
2 abo e: classical Shallow Wa e models, SP and DIP po osi y models (o he po osi y models a e cu en ly
being implemen ed and will be a ailable in nex so wa e eleases). I can be used wi h any ini ial da a and
wi h he ou bounda y condi ion ypes men ioned abo e. Se e al ypes o o cing (p ecipi a ion, in il a ion,
wind, ic ion) a e also implemen ed.
3.1 Inpu iles
SW2D equi es inpu iles p o iding geome y in o ma ion, ini ial and bounda y condi ions, o cing e ms,
pa ame e alues, e c. He e we b ie ly desc ibe he iles needed o a simula ion ( o mo e de ails, see he
online documen a ion on he SW2D si e):
- Mesh ile: SW2D is compa ible wi h he 2DM o ma (ascii iles) p o ided by he Su ace-wa e
Modeling Sys em (SMS) Aqua eo(c) so wa e. SMS can be downloaded om he Aqua eo websi e.
Al e na i ely, use s may gene a e 2DM ile om you own da a using Py hon modules such as
Py2DM. I is also possible o con e 2D Sela in/Se aphin iles (TELEMAC-MASCARET o ma ) using a
dedica ed execu able included in he SW2D dis ibu ion.
The mesh is uns uc u ed. The compu a ional cells may ha e an a bi a y numbe o edges. I is o
example possible o mix iangles wi h quad angles, as long as hese meshes a e co ec ly de ined
in he 2DM ile. The 2DM o ma inco po a es he ele a ion o he mesh nodes, so ha no addi ional
ele a ion da a ile is needed.
Inpu iles a e p ocessed by he sw2dCon e e p og am. This con e e p oduces a bina y ile
con aining all he necessa y in o ma ion o he main SW2D p og am. The o ma o his bina y ile
is speci ic o SW2D. As s essed abo e, sw2dCon e e can ead iles o a ious o ma s, such as
hose om SMS, BlueKenue o Telemac-Masca e .
- Ini ial condi ion ile: his ex ile speci ies he ini ial s a e o he simula ion. The well-posedness o
he shallow wa e p oblem equi es ha he ini ial wa e le el/dep h and he componen s o he
low eloci y/uni discha ge ec o be speci ied o all compu a ional cells. Two op ions a e made
a ailable o he use . I he ini ial s a e is uni o m, only one line is needed (Figu e 1). The alues ead
wi hin his line a e applied uni o mly o all cells. O he wise, he ini ial alues a e speci ied on a cell-
by-cell basis, wi h one line con aining he 3 ini ial s a e a iables o each cell in he mesh.
Figu e 1: Con en o an IC ile o wa e a es (su ace ele a ion = 1m)
- Bounda y condi ion ime se ies ile: his ile p o ides he ime se ies o all he bounda y condi ions
used in he simula ion. The ime se ies a e placed a e a heade speci ying he numbe n and he
ypes o bounda y condi ions. They a e a anged in he o m o n + 1 columns. Fo each line, he i s
column is he ime alue (in seconds) and he emaining n + 1 eco ds indica e he nume ical alue
o he bounda y condi ion a his speci ic ime (Figu e 2). Du ing he simula ion, he nume ical alue
o he bounda y condi ion is in e pola ed using he nea es wo imes in he ile. When he simula ed
ime is la ge han he la ges ime in he ime se ies ile, he las ead bounda y condi ion nume ical
alue is used.
Figu e 2: Con en o a BC ile wi h 3 ypes o bounda y condi ions, all cons an in ime:
ze o discha ge, ee su ace a 8m and F oude numbe equals o 0.7.
Changes in he las line would lead o ime in e pola ion o q ( esp. z,c) a bounda y 1 ( esp. 2, 3) be ween =0 and =86400
- Inpu SW2D ile: his ile speci ies he simula ion se ings: choice o he physical model (shallow
wa e , SP, DIP, e c.), physical and nume ical se ings (simula ion ime ime, ype o bounda y
condi ions, CFL cons ain , ype o ini e olume scheme) and ou pu pa ame e s ( ype and
equency o simula ion esul w i ing). These pa ame e s a e assigned a de aul alue (see he
SW2D documen a ion o mo e de ails) ha may be o e w i en by he use (Figu e 3).
a supp imé: Figu e 1
a mis en o me : Non souligné
a supp imé: Figu e 3

Figu e 3: Sample SW2D inpu ile. The dual in eg al po osi y (DIP) model is sol ed using he i s -o de Goduno scheme. The
simula ed ime is 100 s, he maximum pe missible compu a ional ime s ep (d max) is 1 second and he simula ion esul s a e
s o ed in he o m o maps e e y second.
- [Op ional]: depending on he physical models (po osi y, ic ion, sou ce e ms, e c), addi ional iles
a e needed o he speci ica ion o he co esponding model pa ame e s. The o ma o such iles
is p o ided in he so wa e documen a ion, along wi h sample iles.
3.2. Ou pu iles
The model ou pu s a e s o ed e e y d map seconds. A unique (ascii) ou pu ile is c ea ed o each s o ed
ime. The simula ion esul s a e s o ed on a cell-by-cell basis, wi h one line o each cell (Figu e 4). The
e bosi y o he s o age is con olled in he SW2D inpu ile by a lag ha may ake 3 alues:
- ‘none’: no hing is s o ed
- ‘s anda d’: main a iables a e s o ed (x, y, zb, h, q, )
- ‘all’: all a iables a e s o ed (main a iables abo e, plus wi h addi ional ones such as eloci ies, ee
su ace ele a ion, F oude numbe , e c.)
Figu e 4: Sample ou pu ile ( e bosi y lag se o ‘s anda d’).
3.3 SW2D wo k low
The simula ion wo k low (Figu e 5) consis s o wo main s eps. The i s s ep is geome y p ep ocessing. I
consis s in con e ing he mesh and bounda y condi ion inpu iles o he speci ic o ma equi ed by he
compu a ional engine. The second s ep is he hyd odynamic compu a ion i sel . These wo s eps a e dis inc
because he geome y p ocessing s ep can be ime-consuming and needs o be done only once. This allows
he same model mesh and geome y o be used in nume ous simula ion scena ios wi hou ha ing o p ocess
he mesh again.
SW2D is p o ided wi h a G aphical Use In e ace (GUI) ha makes i possible o launch and isualize he
simula ion p og ess wi hou he need o ex e nal ools (see Sec ion 5). Expe ienced use s may also choose
o bypass he GUI and use he so wa e in command line mode. In bo h cases, he ou pu iles a e s o ed in
a dedica ed di ec o y, a a equency chosen by he use hanks o he d map pa ame e . Du ing he p og am
execu ion, a numbe o log messages can be displayed by he use in a dedica ed window (o in he console):
in o ma ion, wa nings and e o s.
a mis en o me : Non souligné
a supp imé: Figu e 4
a mis en o me : Non souligné
a supp imé: Figu e 5
Figu e 5: Wo k low o SW2D execu ion
4. LICENSING AND INSTALLING
4.1 Licensing
SW2D is he p ope y o In ia (Ins i u Na ional de Reche che en In o ma ique e Au oma ique) and UM
(Uni e si é de Mon pellie ). I has been de eloped in C++ by esea che s o he LEMON p ojec - eam
(common o In ia, UM, CNRS and IRD). Al hough i is s ill unde de elopmen , i is al eady dis ibu ed unde
3 di e en ypes o licences:
Public Resea ch License
In ia and UM g an o he academic use , a ee o cha ge, wi hou igh o sublicense, nonexclusi e igh o
use he so wa e o esea ch pu poses o a pe iod o one yea .
P i a e Licence
In ia and UM p o ide SW2D o any p i a e use (including companies) wi hin he amewo k o a con ac
be ween he pa ies.
Educa ional Licence
In ia and UM ha e o med pa ne ships wi h enginee ing schools whe e SW2D is dis ibu ed ee o cha ge,
s ic ly wi hin he amewo k o he aining o enginee ing s uden s.
I esul s ob ained h ough he use o SW2D we e o be published, au ho s should ci e co esponding a icles,
aking in o ma ion om he SW2D publica ion page. The so wa e is p o ided only as a compiled lib a y ile.
Any decompiling p ocess is s ic ly unau ho ized. Upon eques (in he amewo k o esea ch pa ne ships),
any pa ne may become a membe o he SW2D de elopmen eam and be g an ed access o he SW2D C++
sou ce code.
4.2 Ins alling SW2D
This sec ion p esen s he example o a bina y ins alla ion ile o Windows, simila o he one p o ided o
educa ional pa ne s. The p ocess is simila o any Windows p og am ins alla ion (see Figu e 6 and Figu e 7).
1. Reques he sw2d-ins all-windows.exe ile om he SW2D conso ium and download i .
2. Loca e and double-click he downloaded .exe ile. I will usually be in he ‘Downloads’ olde .
3. A dialog box will appea . Follow he ins uc ions o ins all he so wa e.
a mis en o me : Non souligné
a supp imé: Figu e 6
4. The so wa e will be ins alled. Fo mo e con enience, i is ecommended o add sho cu icons on
he use desk op.
Figu e 6: Ins alla ion p ocess unde windows: i s s eps
Figu e 7: Ins alla ion p ocess unde windows: las s eps
Sample iles, which allow es ing he so wa e, a e p o ided wi h he ins alla ion along wi h a use 's guide.
5. TEST CASES
The p esen sec ion ocuses on di e en es cases buil o eaching. They exhibi he di e en ea u es o
SW2D as he p incipal poin s whe e he 2D low modele should pay a en ion o.
5.1 Ga don es case
This es case aims o model a lood p opaga ion in he Ga don i e nea Ne s (downs eam o Alès, F ance).
I is pa o he eaching cu iculum a Poly ech Mon pellie . This si e co esponds o he ypical con igu a ion
whe e a 2D model should be used, wi h a sha p meande and a complex channel geome y inducing d ying
beds, low di e ion in o pa allel b anches and highly non-uni o m eloci ies ac oss he channel sec ion. The
channel is also subjec ed o widening and na owing, inducing signi ican ans e se low eloci ies. Hyd aulic
s uc u es a e also p esen : a s ong na owing o he loodplain nea he downs eam sec ion due o a oad
embankmen and a sill (wi h a 45 deg ees angle wi h he main low di ec ion) wi h ele a ion a ia ion o
nea ly 2m po en ially leading o ansc i ical low on he s eep downs eam slope. This es case is he e o e
a he syn he ic o ypical i e hyd aulics complexi ies, wi h mixed and compe ing in luences o geome y,
hyd aulic pa ame e s and bounda y condi ions.
Figu e 8 shows he es case si ua ion and he mesh used in he 2D model.
a mis en o me : Non souligné
a supp imé: Figu e 8
Figu e 8: Ga don es case si ua ion and mesh (basemap ©IGN h p://geopo ail.gou . ).
The hyd aulic model is he classical 2D shallow wa e model. The simula ion inpu iles a e speci ied in Table
1.
Table 1: Inpu iles o he Ga don es case.
File name
Objec
ic ion_s ickle _map. x
Dis ibu ion o he ic ion coe icien (uni o m wi h
𝐾 = 50𝑚(/*. 𝑠+(
)
Ga don.2dm
Mesh ile (5178 uns uc u ed cells)
Ga don.bc
Bounda y condi ion ile
hyd o_bounda y_ ime_se ies. x
Bounda y condi ion ime se ies (p esc ibed hyd og aph ups eam,
ime-dependen F oude numbe downs eam)
ini ial_condi ions_map. x
Ini ial condi ions map (uni o m wa e le el and ze o low assigned
uni o mly o all cells)
inpu .sw2d
SW2D inpu ile
The p opaga ion o a p opaga ion is simula ed wi h a p esc ibed ups eam uni discha ge ising om 0.1m2/s
o 15m2/s. Figu e 9 shows he esul s ob ained a he peak ime o he in lowing hyd og aph. As shown in he
sc een cap u e, he GUI allows o a spli iew o isualise se e al a iables a he same ime.
a mis en o me : Non souligné
a supp imé: Table 11
a mis en o me : Non souligné
a supp imé: Figu e 9