This is a short introduction to understand just a little how hydrological models and some hydraulics works. Much relies on the oral presentation. Unfortunately this is is Italian
A short introduction to some hydrological extreme phenomenaRiccardo Rigon
For high School teachers. Kept at MUSE on October 20th 2017. It covers the typology of some phenomena giving a little of explanation of the diverse dynamics. Is a product of LIFE FRANCA EU project
This is the presentation given for the admission to his second year of Ph.D. studies by Michele Bottazzi. Besides sumamrizing the work done during the first year, Michele traces his pathways into the second year with an abrupt change of direction towards simulating and discussion transpiration from plants.
This is the presentation for his admission to the third year of his Ph.D.. It talks about the several direction his work had taken and look forward to the conclusion of some task in form of code release and published papers.
This contains a summary of the data available for torrente Meledrio. We are using it for the project SteepsStreams, and we want to estimate its water and sediment budgets.
This contains the talk given at the 2017 meeting of the SteepStream ERANET project. It is assumed to talk about the hydrological cycle of the Noce river in Val di Sole valley (Trentino, Italy). It is a preliminary view of what we are going to do in the project.
This contains some hints and discussions about how to implement Grids in a Object Oriented language. Specifically the discussion is made with Java in mind, but obviosly, not limited to it.
How to implement unstructured grids in Java (or BTW in another OO language). First start from understanding what grids are and how they are described in algebraic topology. Mathematics first, can be a good idea. No explicit implementation here, but concept and literature to study and start from..
A short introduction to some hydrological extreme phenomenaRiccardo Rigon
For high School teachers. Kept at MUSE on October 20th 2017. It covers the typology of some phenomena giving a little of explanation of the diverse dynamics. Is a product of LIFE FRANCA EU project
This is the presentation given for the admission to his second year of Ph.D. studies by Michele Bottazzi. Besides sumamrizing the work done during the first year, Michele traces his pathways into the second year with an abrupt change of direction towards simulating and discussion transpiration from plants.
This is the presentation for his admission to the third year of his Ph.D.. It talks about the several direction his work had taken and look forward to the conclusion of some task in form of code release and published papers.
This contains a summary of the data available for torrente Meledrio. We are using it for the project SteepsStreams, and we want to estimate its water and sediment budgets.
This contains the talk given at the 2017 meeting of the SteepStream ERANET project. It is assumed to talk about the hydrological cycle of the Noce river in Val di Sole valley (Trentino, Italy). It is a preliminary view of what we are going to do in the project.
This contains some hints and discussions about how to implement Grids in a Object Oriented language. Specifically the discussion is made with Java in mind, but obviosly, not limited to it.
How to implement unstructured grids in Java (or BTW in another OO language). First start from understanding what grids are and how they are described in algebraic topology. Mathematics first, can be a good idea. No explicit implementation here, but concept and literature to study and start from..
This is the outstanding lecture given by Dani Or when receiving his Dalton Prize at 2017 Wien EGU General Assembly. It is a must-read for who deals with ET and good material also for teaching to students.
Projecting Climate Change Impacts on Water Resources in Regions of Complex To...Riccardo Rigon
The title describes it all. Jeremy Pal's student Brianna Pagàn and coworkers put an impressive set of tools to estimate the impacts of land use and climate change on water resources of south California.
This is the English translation, with some relevant corrections, of the talk I gave at University of Calabria, about the contemporary and post-contemporary flood forecasting.
Hydrological Extremes and Human societies Riccardo Rigon
This is the talk given by Giuliano di Baldassarre at the Summer School on Hydrological Modeling kept in Cagliari this here. The topic is very up-to-date and important. He presented an analysis of a few case studies and suggested some literature.
The Science of Water Transport and Floods from Theory to Relevant Application...Riccardo Rigon
This is the presentation given by Ricardo Mantilla at University of Iowa in 2017. It talks about the system implemented in Iowa for flood forecasting in real time
These are the slides presented at EGU 2017 General Meeting, the Pico session was entlited: Monitoring and modelling flow paths, supply and quality in a changing mountain cryosphere
Freezing Soil for the class of Environmental ModellingRiccardo Rigon
This is similar to the lecture Niccolò gave in Ottawa during his staying in Carleton University. This also contains further results from his Ph.D. thesis
Master thesis presentation by Niccolò TubiniRiccardo Rigon
This contains a short presentation regarding the work Niccolò Tubini did for his master thesis. It contains a new theory for transport of water in frozen soils
This is a presentation of the JGrass-newAGE system held in Potenza on February 24 20117. It contains an overview of concepts, ideas, behing JGrass-NewAGE ans shows some achievements in a critical manner.
This is a short introduction to Git, Travis, and Gradle, alls used at command line and jointly with Github. It contains some examples and a few simple exercises that make you to get use to the commands. For further information, please see https://www.blogger.com/blogger.g?blogID=6687556278632539882#editor/target=post;postID=5021188629184529191;onPublishedMenu=allposts;onClosedMenu=allposts;postNum=0;src=postname
A travel time model for estimating the water budget of complex catchmentsRiccardo Rigon
This is the presentation given by Marialaura Bancheri for her admission to the final exam to achieve a Ph.D. in Environmental Engineering. It contains a synthesis of her studies about spatially integrated models of the water budget, and about travel time theory. A model structure is also presented preliminarily containing five reservoirs.
This is a revision of the previous post on the same topic. There I tried to develop my own algebra of symbols to represent coarse grained (spatially integrated) hydrological system. Later on I understood that Petri networks were already there and useful to obtain the same result. The graphs obtained in such a way where, besides, studied in several places, and many contributes of literature convergent from other disciplines, can be used for hydrological scopes.
This is the outstanding lecture given by Dani Or when receiving his Dalton Prize at 2017 Wien EGU General Assembly. It is a must-read for who deals with ET and good material also for teaching to students.
Projecting Climate Change Impacts on Water Resources in Regions of Complex To...Riccardo Rigon
The title describes it all. Jeremy Pal's student Brianna Pagàn and coworkers put an impressive set of tools to estimate the impacts of land use and climate change on water resources of south California.
This is the English translation, with some relevant corrections, of the talk I gave at University of Calabria, about the contemporary and post-contemporary flood forecasting.
Hydrological Extremes and Human societies Riccardo Rigon
This is the talk given by Giuliano di Baldassarre at the Summer School on Hydrological Modeling kept in Cagliari this here. The topic is very up-to-date and important. He presented an analysis of a few case studies and suggested some literature.
The Science of Water Transport and Floods from Theory to Relevant Application...Riccardo Rigon
This is the presentation given by Ricardo Mantilla at University of Iowa in 2017. It talks about the system implemented in Iowa for flood forecasting in real time
These are the slides presented at EGU 2017 General Meeting, the Pico session was entlited: Monitoring and modelling flow paths, supply and quality in a changing mountain cryosphere
Freezing Soil for the class of Environmental ModellingRiccardo Rigon
This is similar to the lecture Niccolò gave in Ottawa during his staying in Carleton University. This also contains further results from his Ph.D. thesis
Master thesis presentation by Niccolò TubiniRiccardo Rigon
This contains a short presentation regarding the work Niccolò Tubini did for his master thesis. It contains a new theory for transport of water in frozen soils
This is a presentation of the JGrass-newAGE system held in Potenza on February 24 20117. It contains an overview of concepts, ideas, behing JGrass-NewAGE ans shows some achievements in a critical manner.
This is a short introduction to Git, Travis, and Gradle, alls used at command line and jointly with Github. It contains some examples and a few simple exercises that make you to get use to the commands. For further information, please see https://www.blogger.com/blogger.g?blogID=6687556278632539882#editor/target=post;postID=5021188629184529191;onPublishedMenu=allposts;onClosedMenu=allposts;postNum=0;src=postname
A travel time model for estimating the water budget of complex catchmentsRiccardo Rigon
This is the presentation given by Marialaura Bancheri for her admission to the final exam to achieve a Ph.D. in Environmental Engineering. It contains a synthesis of her studies about spatially integrated models of the water budget, and about travel time theory. A model structure is also presented preliminarily containing five reservoirs.
This is a revision of the previous post on the same topic. There I tried to develop my own algebra of symbols to represent coarse grained (spatially integrated) hydrological system. Later on I understood that Petri networks were already there and useful to obtain the same result. The graphs obtained in such a way where, besides, studied in several places, and many contributes of literature convergent from other disciplines, can be used for hydrological scopes.
1. Modelli, o meglio, pezzi di modelli
idrogeologici
Riccardo Rigon, Marta Martinengo, Marialaura Bancheri, Stefano Tasin &
Giuseppe Formetta
LIFE 15/IT/000030 REALIZZATO CON IL CONTRIBUTO LIFE. UNO
STRUMENTO FINANZIARIO DELL’UNIONE EUROPEA
VariAutori
2. In questa presentazione si usano varie
foto , mappe e altro trovato in Internet. Cito
sempre la fonte (che spesso è un sito web).
Il fatto che le fonti siano citate, non
significa che vi sia, necessariamente un
“endorsement” di quanto scritto nei siti
web. Molto spesso sono scritte cose
sensate. Ma non sempre.
3. “Co i modei se sbaia.
Figuremose sensa.”*
“Con i modelli si sbaglia.
Figuriamoci senza!”
A. Marani
4. !4
Si comincia sempre da Galileo e Newton
La gravità (una forza) agisce accelerando il grave in moto
Rigon et Al.
5. !5
che nasce in Val Rendena, attraversa Passo Carlo Magno dove si unisce con il Rio Campo Carlo
Magno e scende verso la Val di Sole. In quest’ultimo tratto confluiscono nel Meledrio diversi rii di
dimensioni considerevoli sia in destra che in sinistra orografica.
Sul conoide del Torrente Meledrio si trovano gli abitati di Pellizzano, ad ovest, e di Carciato ad
est che occupano circa il 20% dell’area dell’intero conoide, aree della stessa entità sono destinate
ad attività agricole e ricreative.
Figure 1: Bacino del Torrente Meledrio: vista aerea 3D
2 Analisi geologica
Ne possiamo dunque dedurre che
qui l’acqua è
p i ù v e l o c e
p e r c h è h a
costantemente
accelerato ?
q u i l ’ a c q u a
a c c e l e r a p i ù
v e l o c e m e n t e
perchè c’è più
pendenza ?
andando
Rigon et Al.
Che continuano a valere, ma …
6. !6
Nell’esperimento di Galileo, l’attrito era eliminato il più possibile.
1 Descrizione dell’area di studio
Il Torrente Meledrio è uno degli affluenti di destra del fiume Noce in Val di Sole, ha un’area di
circa 53 km2
e si trova sul versante Nord della Val di Sole. Il Torrente Meledrio si sviluppa tra le
quote 2934 m m s.m.m. e 860 m m s.m.m.1
. Morfologicamente è costituito da un ramo principale
che nasce in Val Rendena, attraversa Passo Carlo Magno dove si unisce con il Rio Campo Carlo
Magno e scende verso la Val di Sole. In quest’ultimo tratto confluiscono nel Meledrio diversi rii di
dimensioni considerevoli sia in destra che in sinistra orografica.
Sul conoide del Torrente Meledrio si trovano gli abitati di Pellizzano, ad ovest, e di Carciato ad
est che occupano circa il 20% dell’area dell’intero conoide, aree della stessa entità sono destinate
ad attività agricole e ricreative.
Figure 1: Bacino del Torrente Meledrio: vista aerea 3D
2 Analisi geologica
L’analisi geologica di riferimento è quella riportata nello studio del Servizio Bacini Montani “Studio
idraulico del Torrente Meledrio attraverso l’abitato di Dimaro” a cura del dott. Silvio Grisotto.
Tale studio si basa sulla carta geologica prodotta dal Servizio Bacini Montani e disponibile in
formato shapefile nella quale sono distinte le diverse classi di permeabilità al fine della valutazione
della risposta idrologica del bacino.
Inoltre il moto del grave Galileiano non modificava la forma del mezzo
Rigon et Al.
Friction
7. !7
WATER RESOURCESRESEARCH,VOL. 28,NO. 4, PAGES 1095-1103,APRIL 1992
EnergyDissipation,RunoffProduction,and the Three-Dimensional
Structure of River Basins
IGNACIORODRfGUEZ-ITURBE,I,2ANDREARINALDO,3RICCARDORIGON,'*
RAFAELL. BRAS,2ALESSANDROMARANI,4 AND EDE IJJ/(Sz-VXSQUEZ2
Threeprinciplesof optimalenergyexpenditureare usedto derivethe mostimportantstructural
characteristicsobservedindrainagenetworks:(I) theprincipleofminimumenergyexpenditureinany
linkofthenetwork,(2)theprincipleofequalenergyexpenditureperunitareaof channelanywherein
the network,and(3) the principleof minimumtotal energyexpenditurein the networkas a whole.
Theirjoint applica,tionresultsin a unifiedpictureof themostimportantempiricalfactswhichhave
beenobservedin thedynamicsof thenetworkanditsthree-dimensionalstructure.They alsolink the
processof runoffproductionin thebasinwiththecharacteris.ticsof the network.
INTRODUCTION' THE CONNECTIVITY ISSUE
Well-developedriver basinsare made up of two interre-
latedsystems'the channelnetwork and the hillslopes.The
hillslopescontrolthe productionof runoffwhichin turn is
transportedthroughthe channelnetworktowardthe basin
outlet.Every branch of the network is linked to a down-
streambranchfor the transportation of water and sediment
butit is also linked for its viability, throughthe hillslope
system,toevery otherbranchin the basin.Hillslopesarethe
runoff-producingelements which. the n.etwork connects,
transformingthe spatially distributedpotential ,energyaris-
ingfromrainfallin the hillslopesto kineticenergyin theflow
throughthe channelreaches. In this paper we focuson the
drainagenetwork as it is controlled by energy dissipation
principles.It !spreciselytheneedfor effectiveconnectivity
thatleadsto the treelike structureof the drainagenetwork.
Figure!, from Stevens[1974], illustratesthis point. Assume
onewishestoconnectasetofpointsinaplanetoacommon
outletandfor illustrationpu.rposesassumethat everypoint
isequallydistantfrom its nearestneighbors.Two extreme
waystoestablishthe connectionwouldbe throughthe spiral
andtheexplosiontype of patterns.The explosionpattern
hastheadvantagethatit connectseveryparcelofthesystem
to the outlet in the most direct manner. Nevertheless it
.rejectsanykindof interactionbetweenthedifferentparts
andthe total path lengthfor the systemas a whole is
case each individualis supposedto operate at his best
completelyobliviousof his neighbors,but the systemas a
whole cannot survive.
Branchingpatterns accomplish connectivity combining
thebestof thetwo extremes;they are shortaswell asdirect.
The drainagenetwork, as well as many other natural con-
nectingpat.terns, is basically a transportationsygtemfor
which the treelike structure is a most appealing structure
from the point of view of efficiency in the construction,
operation and maintenance of the system.
The drainage network accomplishes connectivity for
transportationin three dimensions working against a resis-
tance force derived from the friction of the flow with the
bottomandbanksof the channels, the resistanceforce being
itself a function of the flow and the channel characteristics.
This makesthe analysisof the optimal connectivity a com-
plex problem that cannot be separated from the individual
optimalchannelconfigurationandfrom .thespatialcharac-
terization of the runoff production inside the basin. The
questionis whethertherearegeneralprinciplesthatrelate
thestructureof the network and its individualelementsWith
the rate of energy expenditure which takes place in the
systemas a whole and in each of its elements.
PRINCIPLESOF ENERGY EXPENDITURE
IN DRAINAG.ENETWORKS
1096 RODFffGUEZ-ITURBEET AL,' STRUCTUREOF DRAINAGE NETWORKS
233.1,•--303,3
L- 3.73
Fig. 1. Different patterns of connectivity of a set of equally
spacedpointstoa commonoutlet.L r isthetotallengthof thepaths,
andL is the averagelengthof the pathfrom a pointto the outlet. In
theexplosioncase,L•2)referstothecasewhenthereisaminimum
displacementamong the points so that there is a different path
betweeneachpoint and the outlet [from Stevens,1974].
network; (2) the principle of equal energy expenditureper
unit area of channel anywhere in the network; and (3) the
principleof minimumenergyexpenditurein the networkas
a whole. It will be shown that the combination of these
principlesis a sufficientexplanationfor the treelike structure
of the drainagenetwork and, moreover, that they explain
manyof themostimportantempiricalrelationshipsobserved
in the internal organizationof the network and its linkage
with the flow characteristics.The firstprincipleexpressesa
local optimal condition for any link of the network. The
secondprinciple expressesan optimal conditionthroughout
the network regardlessof its topologicalstructureand later
on in this paperwill be interpretedin a probabilisticframe-
work. It postulates that energy expenditure is the same
equalthesumofthecubesoftheradiiofthedaughter
vessels(see,forexample,Sherman[1981]).Heassumedthat
twoenergytermscontributetothecostofmaintainingblood
flowin anyvessel:(1) theenergyrequiredto overcome
frictionasdescribedbyPoiseuille'slaw,and(2)theenergy
metabolicallyinvolvedin the maintenanceof theblood
volumeandvesseltissue.Minimizationofthecostfuncfi0a
leadstotheradiusofthevesselbeingproportionaltothelB
powerof the flow. Uylings[1977]hasshownthatwhen
turbulentflowisassumedinthevessel,ratherthanlain'mar
conditions,thesameapproachleadstotheradiusbe'rag
proportionalto the 3/7 power of the flow. The secorot
principlewasconceptuallysuggestedbyLeopoldandLang.
bein[1962]in theirstudiesof landscapeevolution.It isof
interestto addthatminimumrate of workprincipleshave
been appliedin severalcontextsin geomorphicresearch.
Optimaljunctionangleshavebeenstudiedinthiscontextby
Howard[1971],Roy [1983],andWoldenbergandHorsfield
[1986],amongothers.Also the conceptof minimumworkas
a criterion for the developmentof streamnetworkshasbeen
discussedunder differentperspectivesby Yang[1971]a•d
Howard [1990], amongothers.
ENERGY EXPENDITURE AND OPTIMAL NETWORK
CONFIGURATION
Considera channelof width w, lengthL, slope$, andflow
depthd. The forceresponsiblefor theflowisthedownslope
componentof the weight, F1 = ptldLw sin /3 = ptIdLwS
where sin/3 = tan/3 = S. The force resistingthemovement
is the stressper unit area times the wetted perimeterarea,
F2 = •(2d + w)L, where a rectangularsectionhasbeen
assumed in the channel. Under conditions of no acceleration
of the flow, F1 = F 2, and then r = p.qSRwhereR isthe
hydraulicradiusR = Aw/Pw = wd/(2d + w), Awand
beingthe cross-sectionalflow area, andthewettedperimeter
ofthesection,respectively.In turbulentincompressibleflow
theboundaryshearstressvariesproportionallytothesqua•
oftheaveragevelocity,r = Cfpv2,whereCfisadimen.
sionlessresistancecoefficient.Equatingthetwoexpressions
for,, oneobtainsthewell-knownrelationship,S= Cfv2/
(R•/),whichgivesthelossesduetofrictionperunitweightof
flowperunitlengthofchannel.Thereisalsoanexpendi•
of energyrelatedto themaintenanceof thechannelw•ch
mayberepresentedby F(soil,flow)P•L whereF( ) isa
complicatedfunctionofsoilandflowpropertiesrepresenf•
theworkperunittimeandunitareaofchannelinvolved'm
theremovalandtransportationof thesedimentwhich0th-
erwise would accumulatein the channel surface.Fromthe
equationsofbedloadtransportonemayassumethatF =
Perchè i fiumi hanno
questa forma, piuttosto
che le altre ?
Rigon et Al.
Bella domanda !
8. !8
https://dribbble.com/shots/1286608-River-Section
L ’ a t t r i t o s i
genera lungo il
c o n t o r n o
bagnato
L a v e l o c i t à
dell’acqua varia
all’interno
Larghezza del fiume
profondità
Rigon et Al.
Un piccolo sguardo di dettaglio
9. !9
In un fiume naturale:
•larghezza
•profondità
•pendenza
tendono ad essere tali per cui tutta l’energia potenziale
(gravitativa) è dissipata e
l’acqua tende (mediamente) a non accelerare
Accelera un po’ andando a valle, perchè il sedimento nei tratti vallivi
di fiume il sedimento, assai più fine, oppone minore resistenza al moto
dei massi che si possono trovare nei ruscelli di montagna
Rigon et Al.
E’ ovvio, a pensarci !
10. R. Rigon
!10
Leopold & Maddock 1953:
Relazioni tra Aree e Portata
Portata fluviale
Velocita piena
L a r g h e z z a
dell’alveo
P r o f o n d i t à
dell’alveo
Direzioni di Drenaggio e Aree Contribuenti
11. R. Rigon
!11
Avisio, after Rigon et al. 2006
Leopold & Maddock 1953:
Relazioni tra Aree e Portata
Direzioni di Drenaggio e Aree Contribuenti
12. R. Rigon
!12
Leopold & Maddock 1953:
Relazioni tra Aree e Portata
Direzioni di Drenaggio e Aree Contribuenti
13. !13
Dunque, andando da monte verso valle, l’acqua nei canali, nelle
medesime condizioni idrologiche, tende ad avere velocità costante.
circa 53 km2
e si trova sul versante Nord della Val di Sole. Il Torrente Meledrio si sviluppa tra le
quote 2934 m m s.m.m. e 860 m m s.m.m.1
. Morfologicamente è costituito da un ramo principale
che nasce in Val Rendena, attraversa Passo Carlo Magno dove si unisce con il Rio Campo Carlo
Magno e scende verso la Val di Sole. In quest’ultimo tratto confluiscono nel Meledrio diversi rii di
dimensioni considerevoli sia in destra che in sinistra orografica.
Sul conoide del Torrente Meledrio si trovano gli abitati di Pellizzano, ad ovest, e di Carciato ad
est che occupano circa il 20% dell’area dell’intero conoide, aree della stessa entità sono destinate
ad attività agricole e ricreative.
Figure 1: Bacino del Torrente Meledrio: vista aerea 3D
http://marcoboschini.it/2017/10/05/arrivera-la-pioggia/
Rigon et Al.
23. !23
Se la velocità è costante, dividendo la distanza per la velocità, si ottiene il tempo
in cui un certo volume d’acqua arriva all’uscita !
Stiamo ponendo le basi per calcolare l’onda di piena.
Implicitamente abbiamo assunto che tutte le gocce d’acqua cadessero
contemporaneamente. Le precipitazioni hanno un andamento nel tempo detto
ietogramma
tempo
precipitazione
Rigon et Al.
C’è il tempo
25. !25
Quello che avete visto nelle immagini precedenti
è un gioco che si può fare con:
•Un sistema informativo territoriale (GIS)
•Un po’ di semplice programmazione (per esempio in Python)
Rigon et Al.
Ma lo potete fare anche voi
26. !26
Mettiamoci ora il sedimento
Supponiamo di avere un geologo a disposizione che ci dica dove c’è sedimento
A.Sperandio
Rigon et Al.
Qui ci vuole il geologo !
27. !27
Vediamo ora dove è instabile
Qui abbiamo applicato una teoria semplificata della stabilità
Rigon et Al.
Qui ci vuole il geotecnico !
28. !28
Vediamo ora dove è instabile
Come di vede, i luoghi instabili, riducono di molto le aree da cui
il sedimento proviene.
Rigon et Al.
E naturalmente nascondiamo un sacco di equazioni sotto quel tappeto
29. !29
Possiamo ora costruire la funzione di ampiezza del
sedimento
per capire, allo stesso modo di come abbiamo fatto con la piena
d’acqua, come il sedimento arriva ai canali.
Rigon et Al.
Futurame
31. !31
TRENT2D
y Evolutive, Natural Torrent
Fase solida
(fluido granulare)
fase,
tinuo
MODELLO MATEMATICO
Ora si possono usare modelli “idraulici” per determinare l’erosione, il
trasporto e la deposizione del sedimento
Rigon et Al.
Qui ci vuole l’idraulico!
32. !32
How hydraulics models works
E’ abbastanza ovvio che questi modelli idraulici debbano essere a
Fondo mobile
per dare risultati realistici.
Questo significa, che, oltre alle equazioni del movimento dell’acqua,
devono avere le equazioni relative al movimento del sedimento.
Rigon et Al.
33. !33
How hydraulics models works
Conservazione della massa
Conservazione della quantità di moto
Conservazione dell’energia
Rigon et Al.
34. !34
Ma nei dettagli si annida il diavolo
Quali dettagli possiamo trascurare?
Possiamo trattare acqua e sedimento
come un unico mezzo (e quindi risparmiare
un po di equazioni) ?
http://rspa.royalsocietypublishing.org/content/470/2170/20130819
Rigon et Al.
How hydraulics models works
36. !36
In una colata di fango, il fango e l’acqua
sono ben miscelati e legati, in alcuni casi chimicamente. Si
muovono come un tutt’uno. Come un dentifricio (fluidi di
Bingham)
Rigon et Al.
How hydraulics models works
37. !37
TRENT2D
y Evolutive, Natural Torrent
Fase solida
(fluido granulare)
fase,
tinuo
MODELLO MATEMATICO
Qui no
Questo è particolarmente importante per stabilire dove la colata si arresta
Rigon et Al.
How hydraulics models works
38. !38
In una colata di detriti, l’acqua e il detrito
si muovono separatamente. Quando l’ammasso rallenta, l’acqua
prosegue nel suo moto e l’ammasso, impoverito di acqua, si
ferma.
Rigon et Al.
La piena: acqua + sedimento + acqua
39. !39
Questo ha una serie di conseguenze sulla
formazione delle portate*
Di solito, l’onda di piena la descriviamo così.
Rigon et Al.
La piena: acqua + sedimento + acqua
40. !40
Abbiamo invece imparato che è così
La piena, contiene sedimento.
Rigon et Al.
La piena: acqua + sedimento + acqua
41. !41
E invece è così*
Cioè oltre al sedimento, almeno in alcuni fenomeni estremi, c’è
anche un “surplus” di acqua dovuto al rilascio delle colate, il cui
detrito è fermo a monte.
*L’idea,tuttadaprovare,èdiAronneArmaniniediolasottoscrivo
Rigon et Al.
La piena: acqua + sedimento + acqua
43. !43
Find this presentation at
Questa presentazione: http://abouthydrology.blogspot.it/2017/10/on-some-hydrological-extrems.html
Rigon and Bancheri
Per avere maggiori informazioni e conoscere l’avanzamento del progetto
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