 Do I remember? Yeah, you have it? Compiling? Yeah, it's okay. We will start with something else Three does anyone on group three as gen form installed and compiled Okay, cool four Yeah, right. All right Okay, okay so the next step for a Everyone that can is to download the assignments. So if you go to the ictp folder, they sent you a email I think Vladimir sent you an email Three days ago Yeah, now there is something called Wednesday You go into Wednesday and you should find input starting case assignments Can you see that didn't you receive an email from Vladimir you sent an email with the to the students with the box Right, he says that And you send the link because I Say that they don't see the files. I don't know why so if you go into the folder You don't see open form open up here. You don't have these what what do you see? What do you have you didn't receive an email with links to this it's not the same okay And you go to the chat and follow this link now. He's also says she's also sending by email. Let me check if it works suspicious link So you should have received an email now with the link Follow the link and you include the password you should land in this page Do you have a new email now? Okay, everyone who is attending online, please use the link and password here from the chat and To everybody here in person will send an additional ml right now Did you receive the email not yet, okay, so you see what I see Okay, so you download it not all of it you're going to open form Wednesday and you do download all files Let's see if I do this if I do this Well, it doesn't matter you can get all the folders. It's not a problem. It's not big Normally once you go to your downloads, you will find the folder We will need to extract it somewhere There is what? They follow There a problem up there because there it's not in the email or there is an email with the link and it's correct Someone received the email and someone did not receive an email But who has that we don't have access to these Right just up there. So it's like four people There is a kind of a regional Problem you're sending another Because the other option is that you joined zoom and you will find the link She sent out another email. Can you let us know when you receive it? Well, there can be a lag Just sent it. So it's summer if it doesn't come immediately Let me know if when it can when it gets to you you have it and there's there's a link now Okay, can you go to the link download everything? So for those of you who have Linux you just Open the while you have to unzip Open it and go to Wednesday for those of you who are using Windows subsystem You will have to move the folder into the subsystem because otherwise it's gonna be very very slow. So how you do it? From Wednesday from your downloads You literally copy paste the thing into the Linux folder How do you find the Linux folder? Usually in the explorer You go to the bottom you will find a Linux you click on it You will find your installations of Ubuntu or I assume you have Ubuntu you go in you will find the file system and You go into home. I assume there is your name in there and You copy it where you want in the home. It's okay. So you can literally or either copy paste or Drag it at that point you should have a Wednesday folder available on Linux so in principle now if you go here you LS you should Sorry You LS you should find a Wednesday folder if you were directly on Linux. You didn't even have to copy paste Can you let me know when you have The Wednesday folder ready who has problems with this Okay, all right. So the first thing we do we open the assignment. So we know what we are doing You can open it on Windows. We don't need to open it on Linux if you're using the WSL alright, so The idea of today is to try to do to start from where we were On Monday using open form and try to repeat the same case using a Community developed tool like GenFoam. This allows us to add Neutronics The idea is to complement the thermal hydraulics with the Neutronics using a different tool We are still speaking about the molten soul fast reactor Geometry is very simple. You have a core Hot like cold like you have a pump heat exchanger The pump and the heat exchanger are porous regions Right said complicated things. We can do that with porous medium first assignment Yeah, yeah, that is something that is different what we had last time was a very simple geometry this time we do a Real geometry It's our glass shaped the reason why these geometries used we'll find it out later So the idea is to start from where we were Which means I will not ask you to redo the CFD calculations because you learned how to do that on Monday, so things like setting up Initial and boundary condition for velocity pressure Creating a mesh all those kind of things are ready to care of it for you. So if you look Into what I gave you inside the Wednesday folder. There is something called starting case Starting case is pretty much what we had Monday. It's just the gen form version of it Which means that pressure of velocity K epsilon are not in zero, but they are in zero With region In there that's what I was explaining to you today and you have three different folders for three different regions So we will not go through these again because this was done on Monday And we will have absolutely have no time to do it again today We will end up at the end of the day having done the same thing Keep in mind the only difference compared to what we did Wednesday is that we are doing it in a case that is Multiphysics, so we are just filling it The fluid dynamics part of it and I did that for you to avoid wasting time on something you already learned So the idea of the first assignment is pretty much to at least Do the things that are very different from standard Open form so I provided you the case with initial conditions boundary conditions Turbulence properties thermo physical properties all those things that we learned how to do There are two things that are different in gen form compared to standard open form One of course is the control dict Control dict is not the same right So something you will have to do is open the case look at the control dict change it as you think It's should be changed My suggestion is go through all the keywords try to understand what each of the keywords is and Try to set it the way you think makes sense most of the keywords are Human readable you should understand what they are So try to go through the control dict and see what you think you can change The other thing you have to change is The momentum source you remember that on Monday We included True Phoebe options a momentum source to make it so that the salt circulates because otherwise you have a Pool with no momentum and it would stagnate right you need to move your salt the way we do it in Open form standard is true Phoebe options You can do that in gen form, but I would suggest not gen form has been tailored to nuclear reactors. So we included specific Capabilities for certain things including pumps So what you will need to do is to set a momentum source to 300,000 kilogram per meter square second Hopefully we got the unit of management right in the Z direction How do you do that? Well, this is part of the assignment So I think we can you know, we have probably we can give half an hour for this trying simply to get what we did on Monday, but with a different tool and trying to get the different options and The thing that changed as I said the control dict and how to set the pump and you may wonder how do I set the pump in gen form I Have some tips Well, the first tip is not even about The exercise is a suggestion when you start something you try to open it in para for more in para view Just look at the geometry look at the boundaries Familiarize yourself with the problem. You can spend a couple of minutes few minutes doing that Now the complicated part the control dict I'm confident it's gonna be easy because you just start time and time Solve things yes or no should be fairly easy The momentum source is not because this is a specific option In gen form and you may wonder well, I do not have a clear documentation. Everything is spread out. How do I find out? There is something in Linux That will always help you out. Do you know the? Crap she rep crap comment you're familiar with it the Linux common that will look to files in a directory and search for a specific keyword and You can imagine that you can go to the gen form tutorials There are several of them. So you enter the tutorials folder in gen form and you do a grep I are I means insensitive to case are means recursive So it will search through all the files Inside the tutorials and it will search for a specific keyword pump That is a easy way to find a control dict A dictionary in gen form where we use the pump May seem complicated, but what I we are saying is just let's try to find a tutorial where Someone uses a pump and let's see how we set it Does that make sense? You can even go farther than that yesterday while playing around I did it because if you do grep pump You will find a lot of things and maybe you want to find Pump in the face properties dictionary, which is a specific dictionary that we use in fluids To set things If you have access to charge EPT you can ask charge EPT give me a linux command to find pump in and File name face properties throughout the folder it will work I tried it it gave me the exact specific command to do that Just a suggestion we live in a world where we have access to generative AI it can help you out a lot speeding up your workflow Can be charge EPT if in your country you don't have access to charge EPT try to take a look if you have access to other Generative AI tools they can help you out a lot They're not necessary, but they will spare you five minutes here and there and at the end of the day Maybe half an hour more to go out with friends So what I will be do now is I will do nothing for like 20 minutes let you play around with this thing We will be here if you have questions you ask we do not want this time to Drive the whole thing on The screen so I'd like you to give it a try and in 20 minutes we will start doing it together In the meantime feel free to ask question The Something I forgot to say You will have to set at solution time of approximately 10 seconds to get to a steady state So you will start from zero or run it for a physical time of 10 seconds After 10 seconds it will be in a steady state So just from zero to 10 only fluid dynamics no energy no neutronics no thermal mechanics only fluid Repeating what we did but we jump on If you have no idea on where to start you let us know and we will get to you This is just for your curiosity. This is how I use chai GPT. I cast I need to find the keyword in files That has the name face properties I'm in Ubuntu and it provided me with this answer find all this thing you include your keyword This string in the terminal will find all the face properties file where the keyword pump is used You can use whatever you want. It's just you can use everything you want It's just it took me like 10 seconds to write these I got these I copied the code I put it into the terminal and it gave me the right answer I They don't have a copy and call it a case on you all this window Disguised Something that might not be obvious is how do you run Gen4? Well, you have to It's like pimple for me. So I in the terminal you've right, but you don't write pimple for me right Gen4 It's spelled capital G E capital N. I will write it for you But it's actually spelled exactly like this You need to be like we were before in the union in the open-form environments You will have to do this source that we did before if you are stuck you let us know Because in like seven minutes, I will start doing the exercise Who managed to run it Anyone else group four Did you manage to run it? Yeah group two Anyone in group two that managed to run it? Did you manage to run it? Anyone in group two anyone in group three you managed to run it? Yeah, all right Couple of minutes and then I will show you what you should have done Hopefully. All right. Let's try to do something together So as I said that two things that are missing is the control dict and the momentum source So this is exactly the string that I got from chat GPT if I Execute that in the folder tutorials hopefully I Get things and it's telling me you there is a keyword name pump in several Tutorials and in several files named face properties So you can imagine that there are a number of tutorials where it can take a look at how to set a pump You may notice That there are several tutorials the suggestion is always take the one that is closest to your case In this case, we have someone that is very very close to your case, which is called 2d MSFR This is an extreme case but very often you will find a tutorial that is similar to what you do and That can give you a lot of information on how to set things So if you look into it This is small. Do you know how you if I can make it bigger? preferences, maybe Hmm, no, I will not give me a sec Proper control Great intro watch And a tab with All right, so if you look into the The face properties of one of the tutorials that by chance is a MSFR You will find several things like I said before you have structures Structures will have a volume fraction. They will have a hydraulic diameter and All of a sudden you will find a pump and you will notice that inside the pump. There is something called momentum source It's exactly what you need Which by the way has exactly the same value that we need How lucky? So you can take this maybe Otherwise, I will write it and you can go into our well Let's do it graphically so that you see what I'm doing in the most more obvious way so inside the case We are modifying things that are Characteristics of our system so in open form every time you have to modify something about models physical properties This kind of things is always in constant We are doing the fluid region So it's gonna be in the fluid region and in the fluid region you have a certain number of dictionaries You will have turbulence properties Is it related to turbulence? No Thermo physical properties. Is it a thermo physical properties? No, the only remaining dictionary is called phase properties You look into it You will see you have a pump and you can add a momentum source This was tricky because this meant understanding that there is a phase properties Understanding that you have the easiest way to look into You know you can go to through the documentation It may take time the easiest look at the tutorials search for a keyword that we use in the tutorials and you will get an answer The answer was actually pretty straightforward this time. Yeah Which was called momentum source Why there are three numbers in there? It's a vector, right? We are in 3d. You need XYZ. We are saying the assignment was give 300,000 kilograms square meter square second in the Z direction with a minus meaning down So if you do that you have covered the part about Properties Now the thing I said was missing again was the control dict Now when you open the system of GenFoam you find things that I told you about you will find top-level dictionaries and then folders for each For each region you will have a fluid region a neutral region a thermo mechanical region Now you can imagine the control dict is something that affects all the region. So it's on the top level You can open the control dict And you will find something that is very similar to the control dict of Oh, sorry, let's me do it again system Hmm, I hate VI I hate VI I'm allergic to it System system system control dict now it's a bit bigger To be okay like this. It's okay. Yeah, that's my problem. I Can open it. I cannot get out of it. Yeah So you open a control dict you will find something that if you're familiar with open foam and as I said before approaching GenFoam You should it will look very familiar to you. You will say the name. We will see the name of the application You will see a start time from start from start time and a start time. Our start time is zero That's the only folder we have so we start from zero Stop at and time and time equal to I Said it in the assignment. I told you run it for 10 seconds. So We go for 10 seconds Delta team these can be a tricky one We are solving for fluid dynamics Delta T is Your initial time step. What is a reasonable time step? while the general suggestion is shoot For a small one because in worst case it will adapt to something bigger But if you start with the time step of one second Your simulation will likely blow up This is way too big if you're familiar a little bit with CFD, you know that time steps have To follow the current number condition CFL condition Which means that your time step normally has to be relatively small how small this is a bit of an art At the beginning when you have to guess You will learn with time to provide good guesses. This case. I would guess for something like One sense of a second is probably a good guess if you want to be very safe you do one millisecond It's a bit extreme, but then it will adapt. Oh Sorry, I was changing the wrong thing Right right control didn't open from things not the gen from thing. We're just saying please write at Selected time steps, and I'm telling them right every second. It's okay. We can write every second Right former purge right. We don't care right precision 8 is very high. It's okay because we will have to do Neutronics We don't care about compression because we are not doing high performance computing Time format we keep it general time precision 8 These are all open form things that you shouldn't even care about them These are Gen from things not open from things solve fluid mechanics. Yes or full. Yes or no Yes, this is exactly what we want to do. So solve fluid mechanics true Simple as that these things will activate the test this fluid mechanics solver Do we want to solve for energy? No is not in the assignment Do we want to solve for Neutronics? Not yet. We'll do it later. We want to solve for thermal mechanics No, I said fluid mechanics 10 seconds liquid fuel. Do we have a liquid fuel? Yeah You just set it to true And this is another not obvious one at just time step. Yes or no You are not supposed to know that if you are familiar with CFD the answer is yes, of course If you are not familiar with CFD, it was a tricky one The answer is true. Why? Because when you do CFD you want the time step to adapt to the velocity So that you respect the current number condition Again, this requires familiarity with CFD You are not supposed to have that and I'm telling you now this should be true If you set false with a sufficiently small time step, you will still get a solution Max delta T we don't care we can put everything you want because it's gonna be smaller than that and this is the current numbers and condition CFD to make sure that your solution is stable the current number has to be smaller than one So I provided it to you already correct. It was one Max power variation we don't care we don't have power in this simulation. Okay, so this was the control dict you can save get out and Hopefully run it If I didn't forget anything And it will run and it will take a while so to go back to what we did You had hopefully you had in every group someone that knew a little bit about CFD and that could tell you look you need to adjust your time step Otherwise Please feel free to ask us when there is something that is really not obvious you ask us We will come and give you an answer for every doubt you might have And the idea was simply to try to get the solution for what we already had It's gonna take a while Unfortunately, WSL is horribly slow. You do it directly on Linux is gonna take half the time My suggestion is that we let it go and I take questions and then we get into assignment to and later we look at the results of this because I don't want to waste 10 minutes looking at this thing running Do you have questions about what we did is there something that is really not clear really not obvious Or is vaguely not obvious and vaguely not clear All clear is a clear clear or clear. I don't want to speak because I'm not sure is Do I say something I? Need doubt. It's okay It's running. Okay, we'll see if it was It will give the same answer to everybody So I will leave this thing running because it's gonna take a while Unfortunately, we decide unfortunately, it was a choice We decided to give you a case that makes sense not a single one loop one dimension We wanted to give you a real case The drawback of a real case that takes a while to run We shout with the part of you Part of you once it's done Same thing. So if you have paraform you just get into that was surprisingly quick. Oh Because I made a mistake You see I will let you know I will show you now. Just give me let me run it again because I Forgot something of course So the calculation time was one instead of ten seconds My mistake I forgot to set to ten seconds the calculation time So let me run it again And then I will show you how to visualize the results if you don't have paraform but you have para view So if you do not have paraform but you do have para view, there is something you can do Inside the case folder you can create an empty file That has an extension dot form So for instance, well if you want to create an empty file that the common in Linux is touch And you call it banana Dot form, okay Once it's created you can open Para view it will take a while you have to be patient with WSL Once you open para view I'm sorry. It's very small. I'm don't know how to make it bigger But if you go to file open and you go to your folder, you will see your banana dot form You open it and You will something that is very similar to paraform It's just a way to tell para view look you are looking into a folder. This is an open form folder So you should have that format Activated so what I'm showing you now is para view. This is not paraform Trick is just when you open a file with para view it has to be a file in the format dot in the extension dot form Because para view has to know what format is the para view you can use it to visualize Tens of different formats. So it's somehow you have to tell para view look. This is an open form folder. How do you do that? You let it open an empty file that with extension dot form Does that make sense if they don't have para form? Yeah, it's just for people that don't have para form Paraform you just enter the folder you type paraform it will work because it's already prepared to read foam Formats when you have para view you have to do this thing You have to let para view know that this is a form format So you will create an empty file with a dot form read it. It will read your case Excuse me, sir. I have a question, please. Yeah, go ahead So can we run gene form in parallel? Yes, you can do it the same way as you do it with any other open form Solver npi run number of processor Gen form Parallel so it's exactly the same way as you do it in any other open form application Okay, thank you very much. You're welcome Actually, if you run if you open para view while the simulation is running this is a good way to check that everything is working because We tell open form we told Gen form to write results every second So you can start looking at intermediate results you should start seeing a solution that forms So like for the moment my computer has arrived to approximately one second So the first result after one second should have been written to disk and that you can read with para view or para form So this is the solution after one second. It's starting to have a shape This is the velocity you have high velocity here. Let me put it in a reasonable Nope, nope Yes Almost You start that something is starting to form this is a CFD an unconvert CFD solution That should converge in 10 seconds. It is now at one So you start seeing things that Happens a Question that I have here we have the heat exchanger Do you know why We get higher velocity in the heat exchanger compared to the pump Well of sudden the velocity increases reason is that Gen form is solving for the real velocity and if you move from a region that has High volume fraction to a region where you have low volume fraction out of conservation of mass your velocity will increase So if you go from a region that is completely filled of fluid and all of a sudden you enter a region Where only 50% of the volume is occupied by the fluid Conservation of mass will imply that your velocity will have to double So in Gen form you will see jumps in velocity when you move from one porosity to another porosity. Yeah Oh To conserve mass flow rate and you have mass flow rate number one and mass flow rate number two One equal to this you will immediately realize that the ratio between velocity is equal Well, the area is the same the ratio between velocity is equal to the ratio between porosity This intuitively should see that right if you have Flow going into something that is smaller it has to accelerate. This is Bernoulli Right while we wait for this thing and we trust that it will work. Let's see if we got another time step That's for cruise out curiosity refresh See now I have another time step Things are starting to look a little bit smoother. We're getting to a real solution after 10 seconds. You will have a solution And there is something I wanted you to notice is that if you looked at the solution we had on Monday Here we had a flat surface and we had a big recirculation area Problem of recirculation high temperatures because this thing it's up and it's not taken away This is the reason why people develop this kind of shape for this reactor It's to avoid the flow to stagnate into the reactor So they actually gave the flow the shape the reactor the shape that the flow likes pretty much This technically we say that we want to avoid flow detachment So this is pretty much a real reactor velocity Geometry, it's 2d the real one is 3d, but it's a good approximation So while we wait, I would like to introduce you to Are you all here first of all? So did you manage to follow what I did change the control dict? change the face properties Is someone not there yet? No, okay Then we will wait that it runs we look at the final results later, but I would like now to introduce the second assignment That is a bit more interesting because we will do something new now. We will do new tronics the second assignment is To start from the previous case So please start from the previous case do not start from starting case start from what you already did for fluids So you pretty much copy paste What we did but this time we want to solve for neotronics Neotronics only no coupling no CFD only neotronics. We just want to have a diffusion solution of our reactor Now if you want to Solve for diffusion You may imagine that you need cross sections right now. I'm not asking you to generate the cross sections So you will find the cross sections already provided in Inputs so if you look back at the folder that I gave you in Wednesday Maybe You will have a starting case that we started to use and we have inputs Inside inputs you find the cross sections you will find things called nuclear data and Then nuclear data axial expansion cloud expansion fuel temperature and so on these are the parametrized cross sections So you will have to put this nuclear data in the right place in Gen4 You may imagine where it is it might be related to the neutral region And it might be related to constants because we are providing constants You will find it but you will have to provide this which is given in inputs And you may realize that you have a new region. You might need a new mesh, right? So in inputs I also provided a poly mesh Poly mesh is the mesh for neutral region. I called it poly mesh underscore neutral region You will need to provide your case with this mesh Okay So the idea is to run a very simple Diffusion case where I gave you the cross sections because it's a long time to generate them You can use open MC by the way, we have a script to Translate open MC format into Gen4 format for your curiosity But this time I gave it to you. It's in the nuclear data files Which are in inputs you will need to provide a mesh which is in inputs You will need to provide the reactor power where to find the power. I will let you search for it It's not so obvious this time But you can Look at tutorials. You can grab there are ways to find it if you cannot you let us know and we will come to you A Suggestion is look at nuclear data. Don't do not just copy paste try to look into it Try to understand how many energy groups How many precursors group? How are we parameterizing the cross sections this kind of things take a look take five minutes for that? What I would like to do is to have an eigenvalue Calculation you will have to search where to set a game that I showed you before there is a place where you can do that If you cannot do that grab a game value, you will find it You will have to set it to true And then I would like to have a solution where we have you know when you solve for things You need boundary conditions, right? You would like to have a solution where we set a zero value so Dirichlet zero boundary condition and Another case where we set a zero gradient everywhere zero gradient is a Neumann zero boundary condition You would like to see how the k effective changes how the flux changes. I have some tips To make your life a bit easier in addition to what I said maybe cannot move my Some suggestions that can make your life easier now imagine you're doing diffusion with 50 energy groups You are solving for all of them, right? And then you may want you know, you know that for every field that you have you have to provide initial and boundary condition Since it's really not practical to include initial and boundary condition for potentially 50 different fields In general we provide something that we call default flux. You'll find it everywhere in the tutorials This is a flux that applies the same initial and boundary condition to all the energy groups. So instead of having to create Imagine you have six groups or eight groups instead of having to create eight Fields that are called flux one flux two flux three and for each one of them give the exact same boundary condition Because most of the time they are the same and the same initial condition You give one that is the full flux. I'm telling you what's the name and you give it You provide the same initial and boundary condition to all the energy groups The other thing is that I'm asking you to give a power of 10 20 megawatts We want to get to a eigenvalue where the flux corresponds to a power of 20 megawatts Now the MSFR is 3 gigawatts Can you tell me why we are giving 20 megawatts instead of 3 gigawatts? Any idea what would be the reason for that? It's not because we want to do lower power There is a technical reason an open-form reason for that Because we are solving for only a wedge. So remember in open-form we do always 3d If you don't wish want to do like in this case axis in metric 2d You have what it is in fact a 3d geometry where the two boundaries Have the wedge boundary But then you have to tell open-form look You cannot have 3 gigawatts in something that has a new aperture of 3 degrees, right? You have to have you have to scale down your power to the wedge Again, sorry, I cannot hear you You have to provide the power based on the geometry are solving for so in this case I mean if you look it from the top Your reactor is more or less like this, right and this is three Gigawatts But what we are solving now is something like this angle is like 2.4. I think degrees So this is lead 20 megawatts is literally three Was multiplied by 2.4 divided by 360 I think is 2.4 you can double check this but the reason is we are solving for a wedge And you cannot say okay. That's why just 3 gigawatts. It would be absurd, right? So that's why we are insisting since Monday always remember gen for open-form is 3d and when you Trick it to do 2d using boundary condition. You have to keep in mind that you are actually solving for a smaller domain So smaller power Of course the power density remains the same, but the overall power does not So I would suggest that you start doing this then we take Lunch break and we continue after but let's give it at least 10 15 minutes to this exercise At least use it to get into the exercise understand the exercise Ask us questions if something is really not clear Sorry Do not hear you. I've been asked whether we are solving for Neutronics or passing information from One mesh to the other we are solving The idea is we forget about the fluids now We don't care anymore. We want to solve for a diffusion equation in the neutral region using the diffusion subsolver of GenFoam Forget about everything we did before we will put things together in the afternoon, but now only fluid we did it Now we try to get the simple diffusion solution using the neutronics mesh. The neutronics mesh is available in the input folder Nuclear data are providing the input folder in the form of files called nuclear data and Nuclear data something something for parameterized cross-section. So we want a solution about Other tips think about boundary conditions as I said we want a zero flux Sorry a zero gradient and the zero flux. We want to see both you will have to play with both We want to have two different solutions The other thing which is important We are doing an eigenvalue calculation. I told you before that an eigenvalue calculation doesn't have the time derivative, right? Think carefully about what it means to do because open form By nature does time dependent. So now you will go in there and set time steps Does it make sense to have time steps? No, but it makes sense to have iterations So you we love to use time steps, but those times will not enter a DDT because there is no DDT This is a very open-formish way to say we are doing iterations So the time step in our case Will not matter you can set a time step of zero point zero zero one or a time step of one thousand What matters is how many times you do your solution and this I can tell you you will need Approximately 100 iterations So you can set a time step fix time step of one second from zero to one hundred or A time stacks time step of one millisecond from zero to 0.1 seconds it doesn't matter because in our eigenvalue Equation we do not have the derivative over time, but we need to iterate So let Gen4 do 100 iterations with the time step that you want. It doesn't matter If you have doubts about me, you let me know but Keep in mind you don't really care and you may not need to adjust the time step Yeah You you see online I just for I've been asked online to repeat why the 20 megawatts And the reason is if you look at our reactor from above It looks like that right? It's pretty much a cylinder If you solve for the entire 3d reactor you have to provide three gigawatts of power We are solving for a tiny slice of our reactor, which is it has an aperture of 2.4. I think degrees So you have to provide the power that is scaled down because otherwise you would provide three gigawatts To a slice of our reactor that doesn't make sense. You have to provide the power that that slice has So it's pretty much three gigawatts Multiplied by 2.4 degrees divided by 360 degrees. That is 20 megawatts I believe check and I remember if it is 2.4 or 2.5. I don't see comments Are there any other comments online? I don't see them. I don't know If you want to generate your own cross-sections you can use whatever tool you want You will need to translate that into a format that is the same of the nuclear data that I showed you We have conversion tool for Serpent and OpenMC So Serpent and OpenMC if you generate your cross-sections You will be able to use our tools to convert them into the various nuclear data files If not, you will have to develop your own conversion tool, but it's easy It's a Python script and you can modify ours for your own tool. I mean it's it's a diffusion Solution and you have access to a field and you can calculate peaking as maximum div is divided by average This is something you can do easily with part of your paraform as a post-processing of your results I still five minutes then at 1245 we go for lunch, okay? so last Suggestion before lunch because this is really not all you so I told you that you have to give the power Where's the power? the target power It is in a file that is called a reactor state you can locate it, but I can show you what it is So that you know when you do this at home and you learn you have time for that today We don't have time to search through everything so I will show you but and Let's take the start in case so you and I told you before we have fluid region neutral region and thermo mechanical region I I did the fact that we have another one that's called uniform And I shouldn't have Now it's because I forgot Inside uniform you have data that do not necessarily belong to One single region. It's data that have impacts throughout all the simulation It's the same logic as why we have Phoebe solution and Phoebe schemes not only in the neutral region and Phoebe and the Fluid region but also on top of the folder. So we have an additional one It's called reactor state and if you look into reactor state you will see two important parameters K effective and P target P target is what you need to set to 20 megawatts. This is the target power And the K effective is the K effect. It's gonna be the result of your calculation But this one is the initial guess you can give whatever you want unless it is unreasonable It's and from we use that as an initial guess and then have it every time step update it with the calculation it is doing But the target power it is in something called reactor state Which hopefully you know if Today here, we don't have much time But hopefully you know if someone does it at home and look at the folder It will realize that there is a file that is called reactor state and hopefully we look into it Today I will tell you it's reactor state and the parameter is called P target and This has to be set to 20 megawatts So this was the last one before lunch as I said so I will let you have lunch and You can ask questions if you want during lunch, otherwise you do it later and we get back here in one hour. So we start again at 145 Please be on time. We have stuff to do this afternoon. We have to couple our solutions and get to our first multi-physics solution