|
[Sponsors] |
March 12, 2018, 04:17 |
|
#201 |
Senior Member
Pablo Higuera
Join Date: Jan 2011
Location: Auckland
Posts: 627
Rep Power: 19 |
Hi Lin,
current and waves are generated in an uncoupled (independent) way. Since the interaction between wave and currents is complex and nonlinear, it's likely that the BC would need some tweaking or specific formulation to provide more accurate results. As a temporary solution I would recommend trying generating the currents as in some experimental facilities: setting a small portion of the floor near one end to have an in-flow BC and another part to be the out-flow area near the other end. Best, Pablo |
|
March 20, 2018, 07:39 |
what is bLims parameter in flapWaveGen.py ?
|
#202 |
New Member
Ali
Join Date: May 2016
Location: Sydney, Australia
Posts: 19
Rep Power: 9 |
hi all,
could any one help me understanding the "bLims" parameter used in the sample falpWaveGen.py file which is used in olaFlow to generate waves via a flap type wavemaker? many thanks in advance |
|
March 20, 2018, 09:52 |
|
#203 |
New Member
Ali
Join Date: May 2016
Location: Sydney, Australia
Posts: 19
Rep Power: 9 |
it was not a difficult question to be posted here. Indeed, it defines the width of each panel in the wavemaker.
|
|
April 29, 2018, 01:14 |
|
#204 |
New Member
aref shahryari
Join Date: Jul 2017
Posts: 10
Rep Power: 8 |
Dear Pablo,
Hi I am wondering if it is possible to change the waveTheory in the wavemakerFlume tutorial (since it doesn't have any waveDicts)? If yes, how? Last edited by Aref.shri; April 29, 2018 at 02:35. |
|
July 2, 2018, 10:44 |
Breakwater tutorial
|
#205 |
New Member
Weather
Join Date: Apr 2014
Posts: 9
Rep Power: 12 |
Hi,
I am not a coastal engineer but quite interested in Breakwater tutorial. The model is the same as given in Higuera et. al (2014) and Guanche et al. (2008). In this tutorial case the given porosity values are not set as in these papers. So this breakwater tutorial case cannot be considered as a validation case on its own, am I right? As far as I know, a and b values given in PorosityDict are set as by try and see method so we need to set the proper porosity values by comparing the results with an experimental data. I was wondering if there is a physical base for the porosity values given in Breakwater tutorial since they are all set different than the ones in the relevant papers. Thank you in advance. |
|
July 2, 2018, 12:19 |
|
#206 |
Senior Member
Niels Gjoel Jacobsen
Join Date: Mar 2009
Location: Copenhagen, Denmark
Posts: 1,900
Rep Power: 37 |
Hi,
The values follow from the recommendation in Jensen et al (2014), which is the basis of the implementation in waves2Foam. As you will find in that reference, multiple combinations of alpha and beta gives a small error, hence it is hard to suggest general values from numerical experimentation. Kind regards Niels
__________________
Please note that I do not use the Friend-feature, so do not be offended, if I do not accept a request. |
|
July 2, 2018, 21:12 |
|
#207 |
Senior Member
Pablo Higuera
Join Date: Jan 2011
Location: Auckland
Posts: 627
Rep Power: 19 |
Hi jovenitta,
check my thesis out (page 259): https://sites.google.com/view/olaflo...del/references Those are a set of the best-fit values from experimental results. Best, Pablo |
|
September 10, 2018, 02:47 |
Random wave generate and propagates separately
|
#208 |
Member
Lewis
Join Date: Jun 2016
Posts: 34
Rep Power: 9 |
Dear Pablo,
I study the tutorial case of random wave in the olaflow, then I set up a 2D case only including 3 single wave components (same wave period, wave period, wave phase, and wave direction). Without doubt, the wave profile is a superposition. Then I try to separate those wave with different wave phases, but I have not been able to achieve this so for. Here is a silly question of mine due to my limited knowledge, I wonder the olaflow can generate series of single wave, and propagates one by one rather than being a integrated wave resulting from wave linear superposition if I plan to simulate hundreds of wave components? Many thanks in advance! Cheers! Lewis |
|
September 10, 2018, 03:51 |
|
#209 |
Senior Member
Pablo Higuera
Join Date: Jan 2011
Location: Auckland
Posts: 627
Rep Power: 19 |
Hi Zuodong,
Yes, as stated in the manual, linear superposition is used to simulate irregular waves. You can specify any number of different components and they will be generated independently. I presume that you have an error in your waveDict. Can you upload it so that I can take a look? Best, Pablo |
|
September 10, 2018, 19:44 |
|
#210 | |
Member
Lewis
Join Date: Jun 2016
Posts: 34
Rep Power: 9 |
Quote:
Now, my waveDict is attached below, it includes 101 wave components and generated from the B-M spectrum. Code:
/*---------------------------------------------------------------------------*\ | ========= | | | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox | | \\ / O peration | Version: 1.3 | | \\ / A nd | Web: http://www.openfoam.org | | \\/ M anipulation | | \*---------------------------------------------------------------------------*/ FoamFile { version 2.0; format ascii; class dictionary; location "constant"; object waveDict; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // waveType irregular; genAbs 1; absDir 0.0; nPaddles 1; tSmooth 1; wavePeriods 101( 1000.00000000000 200.400801603206 111.358574610245 77.1010023130301 58.9622641509434 47.7326968973747 40.0962309542903 34.5661942620118 30.3766707168894 27.0929287455974 24.4498777506112 22.2766763198931 20.4582651391162 18.9143181388311 17.5870559268379 16.4338537387017 15.4225786551511 14.5285485979951 13.7324910738808 13.0191381330556 12.3762376237624 11.7938436136337 11.2637981527371 10.7793467715856 10.3348491112030 9.92555831265509 9.54745083062822 9.19709371838499 8.87154009936125 8.56824608002742 8.28500414250207 8.01988932552731 7.77121541809139 7.53749905781262 7.31743011854237 7.10984713828653 6.91371681415929 6.72811680010765 6.55222120298781 6.38528829576655 6.22665006226650 6.07570326265265 5.93190176770673 5.79474995653938 5.66379700951518 5.53863195790640 5.41887937574510 5.30419561873442 5.19426553085394 5.08879955218564 4.98753117206983 4.89021468042447 4.79662317728319 4.70654680660799 4.61979118543842 4.53617600362894 4.45553377294600 4.37770870726262 4.30255571809655 4.22993951186498 4.15973377703827 4.09182045091861 4.02608905708994 3.96243610571780 3.90076454985177 3.84098329172268 3.78300673375199 3.72675436961950 3.67215041128085 3.61912344830082 3.56760613628255 3.51753491153400 3.46884972942972 3.42149382420365 3.37541348815230 3.33055786844296 3.28687877991060 3.24433053239464 3.20286977131510 3.16245533031846 3.12304809494066 3.08461087633795 3.04710829422878 3.01050666827227 2.97477391718229 2.93987946494194 2.90579415354216 2.87249016172120 2.83994092922867 2.80812108618124 2.77700638711469 2.74657364937241 2.71680069550098 2.68766629935227 2.65915013561666 2.63123273253519 2.60389542755963 2.57712032574801 2.55089026070098 2.52518875785965 2.50000000000000); waveHeights 101( 0 0 0 0 0 0 1.37972248529053e-79 1.46469593520820e-41 1.13557902623205e-23 2.12511083896587e-14 3.14367436266623e-09 3.52965926996490e-06 0.000268471561817300 0.00426791199812591 0.0262145395570040 0.0884379327275092 0.202118589026308 0.356218524666572 0.525773329942840 0.685927915197279 0.820037393338961 0.920818188640956 0.987984681125312 1.02525382529637 1.03800043294934 1.03180114593863 1.01168864027410 0.981862862524877 0.945655658317546 0.905615578643101 0.863636117035623 0.821087814327909 0.778936534449445 0.737841985932257 0.698236330859707 0.660385175827582 0.624433987276199 0.590442918313625 0.558412653762832 0.528303412461296 0.500048799060821 0.473565813259693 0.448762011771043 0.425540572382821 0.403803820063480 0.383455631264000 0.364403024427433 0.346557163931177 0.329833944610610 0.314154279479014 0.299444180321927 0.285634696525875 0.272661759572017 0.260465967423639 0.248992333330033 0.238190016445120 0.228012046441962 0.218415050494868 0.209358988230124 0.200806898241786 0.192724658328759 0.185080760584412 0.177846101749879 0.170993788745351 0.164498958959601 0.158338614662156 0.152491470771739 0.146937815144714 0.141659380520129 0.136639227260544 0.131861636050433 0.127312009749570 0.122976783642389 0.118843343372198 0.114899949898768 0.111135670867435 0.107540317826223 0.104104388773850 0.100819015565286 0.0976759157426056 0.0946673483970219 0.0917860737032408 0.0890253157997151 0.0863787287180891 0.0838403650922791 0.0814046474023904 0.0790663415311877 0.0768205324313053 0.0746626017199474 0.0725882070346717 0.0705932629991050 0.0686739236612602 0.0668265662796398 0.0650477763436366 0.0633343337250020 0.0616831998664351 0.0600915059217553 0.0585565417697348 0.0570757458305642 0.0556466956201781 0.0542670989833309); wavePhases 101( 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633 1.57079633); waveDirs 101{0}; // ************************************************************************* // Cheers! Zuodong |
||
September 10, 2018, 22:23 |
|
#211 |
Senior Member
Pablo Higuera
Join Date: Jan 2011
Location: Auckland
Posts: 627
Rep Power: 19 |
Hi Zuodong,
I think you are confused and maybe not understanding spectra and what you are doing. Spectra represent a sea state and in order to create the free surface elevation time series you need to set the phases randomly. Alternatively, you can also calculate the phases according to linear theory, to obtain a wave focussing. I don't know what your goal is, but you are setting all the phases to the same value, why? Also, you can eliminate the first 6 components, they have amplitude 0 and will not have any influence in the final results, but they add computational cost. Also, I don't understand what you mention about "to make each individual wave propagate one by one". Waves with this method are being generated independently and summed linearly, as you can see in the manual. Best, Pablo |
|
September 11, 2018, 21:30 |
|
#212 | |
Member
Lewis
Join Date: Jun 2016
Posts: 34
Rep Power: 9 |
Quote:
Thanks for your explanation, and I feel more clearer now. Thanks so much! Now, my model is modified to propose the random wave including 101 components ( the significant wave height = 3 m, wave period = 10 s, and water depth = 10 m) based on the B-M Spectra. Refer to the wave phases, I use the Matlab code to generate a series of wave phase randomly between [-2pi, 2pi]. Since the the amplitude of first 6 wave components equal to 0, then eliminating them, so totally there are 95 wave components. The modified waveDict is shown below: Code:
/*---------------------------------------------------------------------------*\ | ========= | | | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox | | \\ / O peration | Version: 1.3 | | \\ / A nd | Web: http://www.openfoam.org | | \\/ M anipulation | | \*---------------------------------------------------------------------------*/ FoamFile { version 2.0; format ascii; class dictionary; location "constant"; object waveDict; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // waveType irregular; genAbs 1; absDir 0.0; nPaddles 1; tSmooth 1; wavePeriods 95( 40.0962309542903 34.5661942620118 30.3766707168894 27.0929287455974 24.4498777506112 22.2766763198931 20.4582651391162 18.9143181388311 17.5870559268379 16.4338537387017 15.4225786551511 14.5285485979951 13.7324910738808 13.0191381330556 12.3762376237624 11.7938436136337 11.2637981527371 10.7793467715856 10.3348491112030 9.92555831265509 9.54745083062822 9.19709371838499 8.87154009936125 8.56824608002742 8.28500414250207 8.01988932552731 7.77121541809139 7.53749905781262 7.31743011854237 7.10984713828653 6.91371681415929 6.72811680010765 6.55222120298781 6.38528829576655 6.22665006226650 6.07570326265265 5.93190176770673 5.79474995653938 5.66379700951518 5.53863195790640 5.41887937574510 5.30419561873442 5.19426553085394 5.08879955218564 4.98753117206983 4.89021468042447 4.79662317728319 4.70654680660799 4.61979118543842 4.53617600362894 4.45553377294600 4.37770870726262 4.30255571809655 4.22993951186498 4.15973377703827 4.09182045091861 4.02608905708994 3.96243610571780 3.90076454985177 3.84098329172268 3.78300673375199 3.72675436961950 3.67215041128085 3.61912344830082 3.56760613628255 3.51753491153400 3.46884972942972 3.42149382420365 3.37541348815230 3.33055786844296 3.28687877991060 3.24433053239464 3.20286977131510 3.16245533031846 3.12304809494066 3.08461087633795 3.04710829422878 3.01050666827227 2.97477391718229 2.93987946494194 2.90579415354216 2.87249016172120 2.83994092922867 2.80812108618124 2.77700638711469 2.74657364937241 2.71680069550098 2.68766629935227 2.65915013561666 2.63123273253519 2.60389542755963 2.57712032574801 2.55089026070098 2.52518875785965 2.50000000000000); waveHeights 95( 6.89861242645266e-80 7.32347967604100e-42 5.67789513116023e-24 1.06255541948294e-14 1.57183718133311e-09 1.76482963498245e-06 0.000134235780908650 0.00213395599906295 0.0131072697785020 0.0442189663637546 0.101059294513154 0.178109262333286 0.262886664971420 0.342963957598639 0.410018696669481 0.460409094320478 0.493992340562656 0.512626912648187 0.519000216474672 0.515900572969316 0.505844320137048 0.490931431262439 0.472827829158773 0.452807789321550 0.431818058517811 0.410543907163955 0.389468267224723 0.368920992966129 0.349118165429853 0.330192587913791 0.312216993638100 0.295221459156812 0.279206326881416 0.264151706230648 0.250024399530410 0.236782906629847 0.224381005885521 0.212770286191411 0.201901910031740 0.191727815632000 0.182201512213717 0.173278581965589 0.164916972305305 0.157077139739507 0.149722090160963 0.142817348262937 0.136330879786008 0.130232983711819 0.124496166665017 0.119095008222560 0.114006023220981 0.109207525247434 0.104679494115062 0.100403449120893 0.0963623291643796 0.0925403802922058 0.0889230508749395 0.0854968943726753 0.0822494794798006 0.0791693073310781 0.0762457353858697 0.0734689075723572 0.0708296902600645 0.0683196136302721 0.0659308180252164 0.0636560048747848 0.0614883918211943 0.0594216716860989 0.0574499749493841 0.0555678354337174 0.0537701589131117 0.0520521943869252 0.0504095077826431 0.0488379578713028 0.0473336741985109 0.0458930368516204 0.0445126578998576 0.0431893643590445 0.0419201825461396 0.0407023237011952 0.0395331707655939 0.0384102662156526 0.0373313008599737 0.0362941035173359 0.0352966314995525 0.0343369618306301 0.0334132831398199 0.0325238881718183 0.0316671668625010 0.0308415999332175 0.0300457529608777 0.0292782708848674 0.0285378729152821 0.0278233478100890 0.0271335494916654); wavePhases 95( 3.13839840845723 -1.33298187956605 -0.537070727721836 -0.220917162180514 1.65849123730671 1.99933494194988 -2.51188214477057 -2.02245082596888 -0.881939849250384 -2.78530658438772 0.137511743186277 -1.03139131046841 -2.03783158740519 -1.82874198157208 2.54565488908837 1.10201526844804 -0.198120143072128 2.58950470675397 -2.48806865515939 1.54281148251827 1.48451220556950 0.388686798410772 -1.98426700641103 0.610796928133897 -1.25703296437796 -2.29887341268478 -1.80577782290566 2.48149173232261 -2.69264139012958 -1.61800466929006 -2.80384384626763 -0.366171114785462 -3.05813184358163 2.49562686057596 -1.90595279505218 -2.55492839459043 -1.21034946618563 -0.276097822050594 -2.50278501337687 3.11262545813017 -1.05499184182141 -1.27330750886617 -2.75175103061357 -1.26767051146971 -2.85035906701236 0.0341060249355167 1.64258729016772 0.823537093270891 -2.57678675419534 -2.63351906467447 1.74195366579891 2.54553667233350 0.212195431137193 -2.45575651226785 2.04711742862726 -1.01726203442105 -1.29450548610706 1.54763290990880 -3.07664576508864 -2.83718904342200 1.05504810790997 0.650108515768986 0.164006629567828 1.44330702999651 1.30221205379562 1.76794415764273 -1.33217995160482 1.20971414802588 0.356067074406176 -0.650179035649927 -2.75460707929693 1.76039478289657 -1.02049067903707 0.677741483660137 1.51584389912991 -2.48303163162404 -2.33804626477828 0.311269672513996 -0.0928063629573366 2.45343105026263 1.87842283126740 1.47240845394706 -2.81906490097873 -2.68364081318172 -2.58535821967966 1.87459376578512 2.78350223351160 1.15431898525628 -2.31169096692148 1.39941955511973 -2.44822128542166 -2.40336329125077 0.884156786036332 -1.07559201063806 0.966429440441339); waveDirs 95{0}; // ************************************************************************* // Cheers! Zuodong |
||
November 26, 2018, 00:05 |
how to set wave absorption at the inlet side?
|
#213 |
New Member
Huang, Chiung Shu
Join Date: Nov 2018
Posts: 12
Rep Power: 7 |
Hi all,
I am running a simple case about solitary wave run-up,which wave comes left to right through a horizon bed to a slope at the right. When the wave run-up at the slope ,and reflecting run down back ,I want the reflecting wave absorpting by the inlet face ,which is like the inlet face is an open patch. However, the default about the inlet is setted to be a wall type and the wave will be reflect again. So I wonder how to do it as I said: set inlet as a outlet patch like. Hope someone can advise me , I am truely a newhand who just learn everything from 0. James. |
|
November 30, 2018, 03:18 |
|
#214 |
New Member
Huang, Chiung Shu
Join Date: Nov 2018
Posts: 12
Rep Power: 7 |
I already find the answer :P
Just set the genAbs value of waveDict to be 1~ |
|
December 6, 2018, 01:25 |
|
#215 |
New Member
Ainal Hoque Gazi
Join Date: May 2018
Location: India
Posts: 27
Rep Power: 7 |
Hello everyone. i am trying to modify the breakwater case in olaFlow.I am abegginer in this field.I am confused about the setFieldDict.....in blockmesh and in setfield the coordinate range is not matched?....any kind of help is appreciated.How to define that range in boxtocell and surfacetocell?Thanks and regards
|
|
December 6, 2018, 01:43 |
|
#216 | |
New Member
Weather
Join Date: Apr 2014
Posts: 9
Rep Power: 12 |
Hi. I wasn't able to open your files but as far as I know they do not need to match. In blockmesh you define the limits of your solution domain. In setfields you primarily define your water depth.
Quote:
|
||
December 6, 2018, 05:43 |
|
#217 |
Senior Member
Pablo Higuera
Join Date: Jan 2011
Location: Auckland
Posts: 627
Rep Power: 19 |
Hi kclement1993,
yes, you are right, active wave absorption for wave generation boundaries can be activated setting genAbs equals to 1. Hi A H Gazi, the coordinates do not need to match. When you define a boxToCell you are setting the value of the cells whose centre is inside the box that you define. This box can be anywhere, but you need to be sure that there are some cells inside it. If you define a box that is outside the domain, OpenFOAM will not complain or warn you, but no cell values will be set. Best, Pablo |
|
December 10, 2018, 22:06 |
chose of \alpha and \beta value
|
#218 | |
New Member
Lin Cui
Join Date: Oct 2017
Posts: 6
Rep Power: 8 |
Quote:
Hi Phicau, Is this set of \alpha and \beta values only valid for the condition described in your thesis? It seems that these coefficients depend on both the porous media properties and flow regime. How do I determine these coefficients if the conditions (geometry of the breakwaters, porosity, wave characteristics, ) changes? I am confused about the determination of these coefficients. Do I use the same values in the TUTORIAL for other conditions? Thanks in advance! Bests, Lin |
||
December 10, 2018, 22:25 |
|
#219 |
Senior Member
Pablo Higuera
Join Date: Jan 2011
Location: Auckland
Posts: 627
Rep Power: 19 |
Hi Lin,
you are right, friction factors are material and flow-regime dependent. Do you have experimental data? -YES. In that case run an array of cases for different parameters and pick up the set that yields the best results. -NO. Try the ones in the breakwater tutorial. You better perform a sensitivity analysis of the parameters to see check the degree of change of the solution with respect to the friction parameters. Best, Pablo |
|
December 11, 2018, 01:17 |
|
#220 |
New Member
Lin Cui
Join Date: Oct 2017
Posts: 6
Rep Power: 8 |
Hi Phicau,
Thanks for the quick reply. I don't have experimental data, I am only doing a numerical simulation with several breakwaters. I have used the \alpha and \beta values in the breakwater tutorial and got the results. you mentioned that it is better to perform a sensitivity analysis. but, if the solution differed significantly, how to determine which results are right which are wrong. Also, do you have a recommendation on the range of these value if doing sensitivity analysis? Bests, Lin |
|
Tags |
generation, ihfoam, olafoam, waves |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Divergence detected in AMG solver: k when udf loaded | google9002 | Fluent UDF and Scheme Programming | 3 | November 7, 2019 23:34 |
udf problem | jane | Fluent UDF and Scheme Programming | 37 | February 20, 2018 04:17 |
UDF velocity profile | willroca | Fluent UDF and Scheme Programming | 2 | January 10, 2016 03:13 |
Error messages | atg | enGrid | 7 | August 30, 2013 11:16 |
Phase locked average in run time | panara | OpenFOAM | 2 | February 20, 2008 14:37 |