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February 27, 2015, 14:03 |
flowRateProfile
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#1 |
New Member
Join Date: Feb 2015
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I am using coalChemistryFoam.
1,In the patchInjection, there is a keyword "flowRateProfile", what doest it mean? 2, If massTotal is 0.001625, SOI=0, duration=0.5, so massFlowRate=massTotal/duration=0.00325, is it right? Anyone can help me?Thank you. |
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May 10, 2016, 22:39 |
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#2 | |
Member
Ping Chang
Join Date: Feb 2016
Location: Perth
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Quote:
I have the same question, what does flowRateProfile mean? |
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May 11, 2016, 11:43 |
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#3 |
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May 11, 2016, 16:37 |
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#4 |
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I'm also working on a Lagrangian dispersion problem.
As far as I understand "FlowRateProfile" specifies the source mass flow rate as a function of time. See for example tutorial ./sprayFoam/aachenBomb/constant/sprayCloudProperites. You could also specify a "sizeDistribution" for the individual particles. Does anyone know of a good documentation source for the Lagrangian Cloud Properties file? I.e. an explanation of what options are and units of parameters? Thanks, Anders |
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May 12, 2016, 21:24 |
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#5 | |
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Ping Chang
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Location: Perth
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By the way, do you know how to count the number of particles after simulation? |
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May 13, 2016, 13:14 |
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#6 |
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I'd like to do massless Lagrangian particles with stochastic dispersion for a steady state, simpleFoam problem (e.g. a RANS problem).
In principle if I have already computed the velocity field this should be a post processing computation. Do you know of any tutorials on how to do that? Unfortunately I do not know of a good way to count particles. One suggestion is that you could export the position of each particle for the timestep of interest and write a Python or Matlab script to search and count in the 3D subdomain. Regards, Anders |
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May 12, 2016, 21:20 |
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#7 |
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Ping Chang
Join Date: Feb 2016
Location: Perth
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Thanks for your reply. Here I have some other questions,
1.after the simulation, do you know how to count the particles number in a specified area? do you have any hints? 2. do you simulate a steady state or transient state? In tutorial simpleReactingParcelFoam, patch is another inlet which inlet air with a certain velocity. can we just inject particles without airflow? If we can, how should we set the BD. Sorry for my poor English. Hope you can understand. |
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March 9, 2023, 12:55 |
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#8 | |
Member
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Quote:
I am using patchInjection in denseParticleFoam. My part of the code is: Code:
injectionModels { model1 { type patchInjection; massTotal 190; SOI 0; parcelBasisType mass; patchName inlet; duration 10; parcelsPerSecond 100644; U0 (0 0 -1.0); flowRateProfile constant 1; sizeDistribution { type RosinRammler RosinRammlerDistribution { minValue 5e-6; // 5 micron maxValue 1000e-6; // 1000 micron n 2.0; // Tuning parameter of Rosin-Rammler distribution d 500e-6; // The size at which 63% mass of particle passes } } } } Second question: If I know the mass to feed (massTotal) and time of feed (duration) then I know the mass feed rate. If I know the mass to be fed in one second and Rosin-Rammler particle size distribution then one can calculate the mass based distribution, e.g. m1 mass of 5 to 100 micron particles, m2 mass of 100 to 200 micron particles, and so on. Knowing the mass and particle dia of each size class, one can calculate the number of particles/parcels in each size class. Sum of them is going to be total number of parcels. How this is different from the defined parcelspersecond. I can see the following output in log file of denseParticleFoam: Code:
Solving 3-D cloud cloud Cloud: cloud injector: model1 Added 10 new parcels GAMG: Solving for cloud:alpha, Initial residual = 5.02715e-07, Final residual = 5.02715e-07, No Iterations 0 Cloud: cloud Current number of parcels = 46928 Current mass in system = 8.86257 Linear momentum = (0.0156862 -0.0522058 -4.25903) |Linear momentum| = 4.25938 Linear kinetic energy = 1.36956 model1: number of parcels added = 46933 mass introduced = 8.8635 Parcel fate (number, mass) : patch walls - escape = 0, 0 - stick = 0, 0 Parcel fate (number, mass) : patch walls_rack - escape = 0, 0 - stick = 0, 0 Parcel fate (number, mass) : patch inlet - escape = 0, 0 - stick = 0, 0 Parcel fate (number, mass) : patch outlet_of - escape = 5, 0.000932727 - stick = 0, 0 Parcel fate (number, mass) : patch outlet_uf - escape = 0, 0 - stick = 0, 0 Min cell volume fraction = 0 Max cell volume fraction = 0.582124 Min dense number of parcels = 1.81128 Last edited by rahulksoni; March 10, 2023 at 03:52. |
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May 18, 2023, 07:18 |
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#9 |
New Member
Turhan
Join Date: Sep 2022
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Hey Rahulksoni,
I have the exact same problem as you and haven't found a way to solve it. However, I noticed that your log file shows the parcel fate for multiple patches. Whenever I run DPMFoam or MPPICFoam I get the Parcel fate for only the system as a whole, how were you able to get the info for individual patches? |
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August 15, 2016, 11:35 |
coal combustion with openfoam
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#10 |
Member
amin jalalian
Join Date: Mar 2014
Posts: 34
Rep Power: 12 |
Hi musabai and other Dear foamers,
I want to simulate coal combustion in steady State but i couldn't find steady solver for it thus I solves it with coalChemistryFoam which is transient until it reaches to steady state . Does anybody have better recommend? Ok, I modified coalCloud1Properties to this: Code:
type patchInjection; massTotal 0.09167; parcelBasisType mass; SOI 0; patchName in_1; duration 20; U0 (26 0 0); massFlowRate 0.004583;//kg/s parcelsPerSecond 1e5; flowRateProfile constant 1; Is this work right? Is "flowRateProfile constant 1" right? I think it means to uniform profile for particle inject with 'massFlowRate= 0.00458'. Am I right? I set 'parcelsPerSecond = 1e5' approximately. I don't know what must I put exactly. Is it a normal input for it? I excuse because of my poor english writing. Best Regards. |
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September 15, 2016, 05:41 |
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#11 |
Member
amin jalalian
Join Date: Mar 2014
Posts: 34
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April 3, 2018, 05:21 |
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#12 |
Member
vishal
Join Date: Mar 2013
Posts: 73
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Hi...any one figured out what "flowRateProfile" stands for?
I am having a doubt whether it stands for mass flow rate as a function of time but then we do mention massFlowRate in injection model, then why to mention it again? |
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June 5, 2018, 07:41 |
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#13 |
New Member
Dami Og
Join Date: May 2018
Posts: 2
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FlowRateProfile is a means of varying injected mass flow rate with time by creating a time profile. If you go with the "constant" FlowRateProfile, only one flow rate value will be used throughout the injection period. Alternatively, you can vary the flow rate by making a table with different flow rates at different times during the injection period.
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November 10, 2020, 12:05 |
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#14 |
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Join Date: Mar 2019
Posts: 81
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Dear Foamers,
I am trying to simulate a pure pressure driven flow through a nozzle using speayFoam in OpenFoam1812. I would like to obtain the mass flow rate through the nozzle. Here is the relevant info from sprayCloudProperties file: Code:
injectionModels { model1 { type coneNozzleInjection; SOI 0; massTotal 1e-5; parcelBasisType mass; injectionMethod disc; flowType pressureDrivenVelocity; Pinj constant 1e6; outerDiameter 2e-4; innerDiameter 0; duration 50e-3; position (0 0.5 0); direction (0 -1 0); parcelsPerSecond 20000000; flowRateProfile constant 1; I really appreciate your thoughts on this. Regards, MJ Last edited by mm66; November 11, 2020 at 09:15. |
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November 16, 2020, 15:21 |
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#15 | |
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November 25, 2020, 09:36 |
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#16 | |
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