Optimization - Recent Threads

RE: Creating a blade cutback in Autoblade

AlexandreGouttiere — Mon, 29 Jul 2024 10:36:26 GMT

Dear JosephSmith,

Shifting the hub leading edge coordinate in the meridional view is a good idea but you have to combine it by moving an other parameters, the refence tangential location.

What I recommend you is playing with:

Hub leading edge in the meridional view (this is what you have done)
Playing with the value of this reference tangential location of the leading edge at section 1 (hub)

You can observe the modification by plotting the parameter theta as a function of the mean_line_length_fraction

Creating a blade cutback in Autoblade

JosephSmith — Wed, 26 Jun 2024 12:56:36 GMT

Good day,

I am currently parametrizing an impeller blade geometry in Autoblade. I would like to shift the hub leading edge coordinate, denoted by B, along the base of the blade to point C as per image 1.

This operation would be an attempt to replicate the cutback angle performed in CAD, shown by image 2,3 and 4.

I attempted to replicate the cutback angle effect in Autoblade by shifting the hub leading edge coordinate in the meridional view. However this results in moving coordinate B radially closer to the axis of rotation like the image below:

instead of smoothly along the blade. This is shown by the upstream leading edge shift in the meridional views of images 5/6.

Ideally, point B should follow the curvature of blade however this was not the case. I believe I am missing an aspect in this regard to fully replicate the CAD cutback operation in Autoblade. In this regard, I would like to know if such an operation is possible

Thanks

FINE Design 3D .FD3 Error

JosephSmith — Wed, 10 Aug 2022 10:13:12 GMT

Hi Everyone,

It is me again. I had been running a FINE design 3D optimization and had received a .FD3 Error. It is seen in the following images:

These issues had occurred after a windows update, I believe.

Prior to this update, the database generation had run successfully, and the optimization was running. However, when I looked at my PC after a while, I believe an update and reboot had occurred, leaving the first optimization incomplete.

I created and tried to run a new optimization. However, I was met with the following images:

Entering my credentials did not work so I had rebooted the PC. After that, it allowed me to run the optimization. However, that is when the .FD3 error occurred. Running the database also resulted in this .FD3 error

The job files displayed this error:

I would appreciate any help on how to resolve this error.

Kind regards

RE: FINE Design 3D .FD3 Error

JosephSmith — Mon, 02 Jan 2023 10:32:50 GMT

Dear Alban,

No problem, and I also hope you have a good 2023.

I believe I followed those steps for registering my account in the user configuration with admin privileges. However, I did not click accept when a firewall popup appeared at some point in the process. I then ended reverting the PC to windows 10, and repeated the process, accepting all permissions. Doing so resulted in resolving the issue.

Thank you for the advice

RE: FINE Design 3D .FD3 Error

aligout — Mon, 02 Jan 2023 09:33:01 GMT

Dear Joseph,

I am sorry for the delay in my answer and I wish you all the best for 2023.

Do you have admin permissions? Indeed, the intelMPI registration encrypts and saves the login and password information in the registry database. For this operation, you would need some admin privilieges. Have you tried to use the admin tool for your intelMPI account configuration? I mean, when you start the admin tool, you can go to user configuration and register your account from this page. An other option is to start a DOS console with admin privilegies, go in the directory fine161\impi5 and use the command "mpiexec.exe -register". Then, you will need to provide your login and password. Finally, in order to check that the operation is successful, you can use the command "mpiexec.exe -validate". This will check if the information has been properly saved in the registry database. If it fails and if you have the admin privilegies, it may be linked to the windows 11 platform that is not officially supported yet.

Best regards,

Alban

RE: FINE Design 3D .FD3 Error

JosephSmith — Thu, 11 Aug 2022 15:05:32 GMT

Hi Alban,

Thanks for the suggestions. I registered for Interl MPI library and tried running one of the optimization samples from Task Manager. Unfortunately the credential page came up again. I decided to enter my details and I still did not have luck:

Kind regards,

RE: FINE Design 3D .FD3 Error

aligout — Thu, 11 Aug 2022 14:23:23 GMT

Dear Joseph,

It's good that you have reproduced the issue in the taskManager. It will speed up the debugging process as you don't need to run the design3D process for reproducing the issue. However, the error message is different from the one of Design3D but may be related. In the admin tool, could you check your user configuration? Could you register your account for the Intel MPI library? After that, you can try again to start your flow computation from the taskManager and the interface shouldn't request you your credentials anymore.

The temporary deactivation of the antivirus is a possible option at least in determining if it is at the origin of the problem or not.

Best regards,

Alban

RE: FINE Design 3D .FD3 Error

JosephSmith — Thu, 11 Aug 2022 14:11:20 GMT

Hi Alban,

To be honest I am still abit confused as to your 1st paragraph as I am largely unfamiliar with Task manager in general. Out of curiosity, I made a new task and defined the subtask as eranus turbo. I chose the run file from a failed optimization sample and tried running it. However was met with the same error:

Running the diagnostics test resulted in the automatic server option displaying as Failed:

The firewall status seemed to have Passed. Would temporarily disabling the antivirus on the PC make a possible difference?

Kind regards,

RE: FINE Design 3D .FD3 Error

aligout — Thu, 11 Aug 2022 12:08:02 GMT

Dear Joseph,

I am sorry but I should have been clearer. I didn't mean to run the design3D computation from the taskManager but the flow solver computation. Design3D starts the computation as the taskManager. That's why I proposed to perform this test.

I've checked on the net the error and it seems that a socket error 10013 can be caused by antivirus or firewall software. Basically, a needed socket connection is being denied. Socket error 10013 is a message which implies that a port is blocked and/or unreachable. Could you try to open the admin tool and perform the different diagnostics especially the "firewall status". If any issue is detected, it should propose you to fix it.

Please note that the windows 11 platform is not officially supported yet.

Best regards,

Alban

RE: FINE Design 3D .FD3 Error

JosephSmith — Thu, 11 Aug 2022 08:34:56 GMT

Hi Alban,

Thanks for the reply. I have indicated details of the pc I am using on windows 11:

- I had left the default Intel MPI as the solver choice

- To be honest I am not particularly familiar with running simulations via task manager. Would the steps to run the optimization via task manager be:

1. Switch to the Task manager module

2. Create a new task under the Task List option

3. Create a new subtask under the Task Definition option. I am not sure which run file from the Optimization directory would be used ( the run file with the project name (small file size) or the run file with the name: project name_computation_1. I have attached images of this scenario:

I am uncertain if these are the right steps

Kind regards,

RE: FINE Design 3D .FD3 Error

aligout — Thu, 11 Aug 2022 07:25:00 GMT

Dear Joseph,

Could you indicate us the version of windows that you are using? In the processor management page, which solver have you selected: intel MPI or MPICH2? According to your choice, could you try to run a parallel computation from the taskManager using the same executable? This is for narrowing down the problem. If you reproduce the problem in the taskManager, we can investigate the reason and the resolution of this problem will also solve the design3D issue.

Best regards,

Alban

RE: How to manually set max iterations on Design3D

JosephSmith — Thu, 28 Jul 2022 17:11:49 GMT

Alright, thanks for the confirmation

How to manually set max iterations on Design3D

JosephSmith — Sun, 10 Jul 2022 11:30:21 GMT

Hi Everyone,

My question is how to manually set the max iteration to run each simulation in the database for Design3D. context: I am attempting to start a multipoint optimization of a centrifugal impeller with water as the fluid. I am using the Spalart-Allmaras turbulence model with the following boundary conditions in the turbo solver:

The Barotropic Cavitation model within Fine turbo is enabled. I only changed the saturation pressure based on the operating temperature, and Amin value to 80 based on a rough calculation of the speed of sound in the two phase medium.

The initial simulation converged to global residuals of -3.8 with the above selections. However, all the samples failed to converge in design3d. It was not a mesh failure, only convergence errors. Opening up the job_eranus files for each computation showed that sometimes the simulation would stop at just 200 iterations. Other times it would stop at 3000. I've summarised them below

I suspect the convergence would improve if I manually set the max iterations to 5000, like my initial simulation. I would like to know how to do this in fine design 3d as I only saw the option to set the convergence level. Alternatively, I would appreciate any other angles to resolve the error.

RE: How to manually set max iterations on Design3D

domen — Tue, 26 Jul 2022 07:20:01 GMT

OK, thanks for the feedback.

[quote userid="544645" url="~/cadence_technology_forums/computational-fluid-dynamics/f/optimization/52041/how-to-manually-set-max-iterations-on-design3d/1384563#1384563"]Does the screening process reset convergence when it uses the initial fine turbo simulation?[/quote]

No, it doesn't. Fine Design3D just runs the CFD solver with the options and settings stored saved in the project (and run file).

Wrt the residuals: since there is scaling, the number of iterations on the coarser grids, the initial solution, and CFL have their weight. It is, of course, important to see the residuals going down, but in some cases, just the global residuals don't tell the full story.

RE: How to manually set max iterations on Design3D

JosephSmith — Sun, 24 Jul 2022 13:49:44 GMT

Thanks for the reply.

1. I have not identified how that occurred yet. I made a duplicate of that initial simulation. In this duplicate simulation in Fine turbo, I used the old original simulation run file (the simulation that converged to -4 as the initial solution. However, I clicked on the ''reset convergence'' option. With this checked, the simulation converged only to -2.3. Does the screening process reset convergence when it uses the initial fine turbo simulation?

I decided to restart from the beginning after running out of ideas. I imported my impeller parasolid into autogrid, and did a preliminary mesh. I used the geomturbo file outputted from this preliminary mesh as the target model for autoblade. I then parametrized the impeller in autoblade as usual.

I exported a geomturbo file from this autoblade parametrized impeller. I then opened up autogrid, and initialized an autogrid project from this autoblade exported geomturbo file. I meshed it and then ran a fine turbo simulation using it. However, something peculiar happened-
the global residual became flat at only -0.8 despite being the same type of geometry as my first few sims that converged at -4. The LE was slightly differed compared to the 1st sim, but the mesh quality was very similar, and the BC were the same. Still working out how that happened.

2. To be honest how each residual in a cell is collected as one and scaled is abit of a black box to me so I can't quite give an opinion on the 2nd point. I'll be looking into some background and get back to you

RE: How to manually set max iterations on Design3D

domen — Tue, 19 Jul 2022 15:36:31 GMT

Sure, here my thoughts:

1) ok, let me know how it goes your investigation.

2) that's pretty normal. Fine scales the residuals to the ones at the first iteration, so the convergence depends on what happens at iteration 1. We rather look at the global data (efficiency etc) and add a control point if needed. When we restart, the scaling can even produce even residuals that are a few orders of magnitude bigger, (+1, +2).

3) you can see residuals for each group if you enable this option in the Control variables box:

If the simulation doesn't converge well, then I'd look at where the residuals are higher in the Monitor. Otherwise, if the convergence curves for efficiency/pdiff are ok (flat, not oscillating, stable) I'd consider the run ok. Watch out: any oscillations in the p_diff can create _a lot of_ noise on the surrogate model.

RE: How to manually set max iterations on Design3D

JosephSmith — Sat, 16 Jul 2022 18:08:52 GMT

Hi Domen,

I've encountered a few issues that i'd like a second opinion on if possible:

1. The Screening simulation's final residual at my imposed 6000 iterations was -2.4. Something seemed usual as the 3d associated computation I used reached residuals of -4 at this point. I'm still looking into how this discrepancy occurred.

2. Setting the requested convergence level to 3 and allowing 6000 iterations to be the stopping point has been resulting in more converged solutions in the database, thanks for that tip! However, upon checking the residuals via the Monitor module, I noticed that some residuals only reached a minimum value of -1.6 but was considered a successfully converged solution in the database:

Using this method of setting the iteration as the stopping point, my question is does this imply that any simulation in the database will be considered successfully converged as long as it reaches the 6000 iteration mark?

3. When using the Monitor to check the residuals progress with each database simulation, I noticed that there was a block button and I assumed the displayed residual corresponds to the selected block. If this is the case, then how would one assess convergence; would each the residuals in each block need to be checked?

RE: How to manually set max iterations on Design3D

JosephSmith — Thu, 14 Jul 2022 08:32:34 GMT

Alright thanks, will try it out and let you know the outcome

RE: How to manually set max iterations on Design3D

domen — Thu, 14 Jul 2022 08:04:32 GMT

1. yes, perfect!

2. No, I'd set it higher (+3). I let Fine Turbo converge (or not), and not Fine Design3D assess the convergence.

RE: How to manually set max iterations on Design3D

JosephSmith — Wed, 13 Jul 2022 13:27:57 GMT

Hi Domen,

Thanks for the advice and sharing your approach. I would like to clarify a few things regarding it:

1. for the ''create a _restart_computation from previous one'' - does this mean creating a new fine turbo project and using the run file from the first converged solution as the initial solution (in fine turbo, going to the Initial Solution> from file> selecting the run file of the first converged simulation)?. If that is the case, you then change the convergence to -10 for this second simulation so the number of iterations becomes the stopping indicator for the simulation

2. For the design3D case, do you actually mean lower? like -4 etc. Besides more result fidelity, is there a reason to lower it in this scenario?

RE: How to manually set max iterations on Design3D

domen — Tue, 12 Jul 2022 10:30:42 GMT

The bad news: when the simulation stops at 218 iterations is because it diverged. You can see the residual for the continuity equation goes from -1 to +2, with the maximum going to +40.

The file job_euranus stores the content of the *.std file produced by Fine Turbo. You can also open a monitor and look at the residuals of the simulation to get a better idea of what's happening. By looking at the files, it seems that the max residual is in block 5, which should correspond to the leading edge of the impeller (not betting any money on this).

The good news: there are a few tricks to make the optimization faster. My favorite option is to restart all simulations in the DoE from an already converged solution and "reset the convergence". Supposing that the geometry changes a little (a few degrees for the blade angles, something along these lines), the flow field won't be too dissimilar, therefore it represents a great initial solution for the other designs.

This means that the convergence level is not going down too much (maybe to -2), so better add a few iterations more to be sure to have a converged solution.

My favorite approach:

- run a geometry and get a converged solution

- create a _restart_ computation from the previous one: this is the computation that I'm going to use for the optimization

- in Fine Turbo, the convergence level is -10, the max number of iterations is to be chosen appropriately. The solver will run until reaching the max number of iterations, since the residuals won't go to -10.

- in Fine Design3D, go to Simulation settings, turn on expert mode, set the convergence level higher than -3. Fine Design3D will consider that all simulations with the job_euranus showing a last line with a residual higher than the number you have there.

RE: Design3D Screening error: No mesh quality report file found or readable

JosephSmith — Tue, 05 Jul 2022 21:00:14 GMT

Thanks domen. The mistake I made was selecting the fluid as Compressible, instead of incompressible, in the Simulation Setting within Design3d. Choosing incompressible resolved the errors.

Design3D Screening error: No mesh quality report file found or readable

JosephSmith — Tue, 28 Jun 2022 17:58:36 GMT

Hi everyone,

I have been trying to set up an optimization project in Design3D. It is for a centrifugal impeller with a blunt trailing edge (its a constant dmr blunt type). I had run an initial simulation in fine turbo and made a parametric model of the geometry in Autoblade. I used the geomturbo file from the Autogrid mesh as the target model for the Autoblade modelling.

My problem lies when I try running the Screening operation in Design3D. I get the following error seen in image 1 which appears after STEP 4 Mesh quality failed in the Task manager tab

Opening view computations info shows the following information:

The quality report file was missing from the above directory. It was only in the directory where I saved the Autogrid mesh files. So, I then pasted the MKS.quality report file in the above directory ( \_trk\_flow\_mesh). The same error still appeared even after adding the quality file to the directory. I suspect maybe its the ''not being readable'' error now.

I am not quite sure how to resolve this error and would appreciate any help. This error did not occur when I did the desgin3d tutorial 1

RE: Design3D Screening error: No mesh quality report file found or readable

domen — Tue, 05 Jul 2022 08:23:49 GMT

Make sure that in the output of Fine Turbo you have selected everything you need to compute those quantities ?(total pressure, temperature...).

Some values are extracted from the mf file, but others are computed in CFView.

Tip: always look for the job_* files (in Linux at least). They are where all programs log their actions. It's the best way to understand what went wrong.

RE: Design3D Screening error: No mesh quality report file found or readable

JosephSmith — Thu, 30 Jun 2022 11:37:32 GMT

That resolved the error! Thanks for the help.

I went past the screening process but was met with the following error

It seems to be related to the quantities I selected in the outputs within Design3D. Some of the outputs I selected were new in Design3d and did not appear in my initial fineturbo simulation, such as P_min of Blade. I suspect that may be related to the error.

Edit* I had left it on Compressible, instead of changing it to Incompressible in the Simulation Settings tab. It is now resolved