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Hi everybody, I recently tried my hands on integrating CAESES with fluent and i think its worth sharing for those who work with fluent and will like to use CAESES parametric models. Please find attached a copy of my project file. its a simple meta-surface elbow i designed with an ellipse curve.Functions for the "width and "height" of the curve are defined. you can have a look at how parameters are set from function curves. I used ICEMCFD as my meshing tool and Fluent as CFD solver. specific files such as the *.rpl and *.jou were used as input files( checkout the attachments). Absolute paths should be changed to relative paths via "getdesigndir()...." (not all paths are necessary!). A *.bat file, RunFluent.bat, was used to run both ICEMCFD and Fluent in batch mode. Snapshots, graphs etc from fluent can be included as results files for post processing. Details on post processing can be found in CAESES tutorials " getting started". You can have a look. Suggestions are welcome. Best regards, Richard "N.B: CAESES is one of the most powerful softwares for tight integration with CFD softwares for DoE and Optimization. All you need to know is to understand how your External CFD software handles its files to know exactly which input and result files to use. it must also have the capability of running in batch mode." Project1_elbow.fdbc

Hi together, please find attached a parametric model of a costa bulb and a feature definition. To recover the energy which gets lost by the hub vortex of the rotating propeller a costa bulb can help. I integrated the rudder bulb setup into the feature "Spade Rudder" which is shipped with CAESES/FFW. The bare hull to which I attached the appendages is also shipped with CAESES/FFW. All you need as input are some propeller parameters. Please find the feature here: baseline > abdy > appendages > feature:rudder Cheers Matthias (fdb file edited, 30.09.2014) containerVesselCosta.fdb

Hi Gabriel, Maybe using fv_all() command would be a better alternative. Please check the picture below; Basically, the fv_all command provides an objectlist. MyCurve.fv_all(0,myPoint:x) The command is applied to a curve. The first argument "0" refers to x-axis The second argument refers to the value on the selected axis. So result will be a list of points that have the same coordinate component value in the referred axis. As seen on the picture above, the curve would have two locations with the same x-coordinate value. Using "at(1)" I pick the second item within the objectlist (0 would be used to pick the first one). And finally I cast the entity to a FVector3 type object. Please let me know if you need further assistance. Cheers Ceyhan

Hi Thomas, Your code seems to work fine and sets the knot vector correctly for the b-spline curve. However, the display field of double series attributes in feature definitions has a small bug. So to see the values of the knotVector doubleseries you can drag and drop the "knotVector" into the console field and press enter. Cheers, Hedi

Hi CJ, if you check the documentation for "units" you should find this: Cheers, Heinrich

HI everyone， I'm having a hard time. I created the blades and tips. As shown in Fig. However, when I create the propeller with Model-propeller-propller, I only get incomplete blades. The tips were not created together. This is shown in the image below. Also, due to the language, I may have a problem with the description not being clear, so please forgive me. Looking forward to your answer. prop_para.cdbc

Hi CJ Coll, I edited the feature so that the labels are not on top of each other anymore and the points are removed inside the profile view. You can find the edited linesplan feature attached to this reply. To toggle the visibilty of the orientation points from the group section curves, you can use the command .setShowOrientation(true/false). If you want to further edit the feature yourself, you can access the it in your CAESES installation directory under "CAESES...\etc\features\features\Maritime". To add a line that follows the topdeck, my solution was to create an image curve from the hull's surface/brep upper edge. I hope that solves your problem. If not, don't hesitate to ask. Linesplan_edited.fde

Hi Furkan, at the computation object, there is an option to set a list of constraints. If one of these constraints is violated, the computation will not be executed for that design. Cheers, Mattia

Hi Yukai, The force in the last line is the converged value from the solver. I would suggest to use a python code only for post-processing. For example, if you want to plot the convergence history of the forces over OpenFOAM iterations. By parsing various values, such as force in x-axis to parameters and establishing a robust integration CAESES with OpenFOAM, then you can continue with a Design of Experiments and/ or with a Optimization process. Best Regards, Andreas

Hi Yukai, OpenFOAM is notably complex when it comes to managing numerous processed files. To address this complexity, I've included a screenshot featuring a standard connection input file, geometries, output files, and corresponding values. It's advisable to consistently employ relative paths by utilizing the subfolder option, as illustrated in the second screenshot. To extract parameters from the force.dat file, you can directly navigate to the last line, which typically represents the converged value from OpenFOAM. This can be achieved using the -1 option in the command line. Moreover, consider incorporating a Python file for post-processing and integrating it into your connection. This can be facilitated by incorporating the Python script as a command line within the Allrun.sh executable file. Best Regards, Andreas

Hi CJ, from visual diagnostic, it looks like a misplaced point - maybe a sign error or a bad dependency? Actually It depends on how you set up the keel line, especially the point or curve, which is going crazy. You can take a deeper look at the faulty design(s) by double clicking on it at the Result Table, or below the Object Tree at the Optimize workspace. BUT only apply changes the baseline design - every change you make inside an other design than the baseline, will not be considered for further design engines - these are always based on the baseline. But you can try out solutions by unlocking the design -> Search for your keel line and its sources. You can check the dependencies of the problematic curve. Right click on the object inside the Object Tree and select "Show Dependencies" - at the upper left corner of the Dependencies window you can switch "Show Clients" or "Show Supplier". Hope that helps, Best, Carl

Hi Yukai, you can set the sub folder by adding it to the file name of your template like this: If you have an allrun script which you execute for each design this would normally be executed in the same location as your STL file is exported to. Hence, typically referring to it by its name instead of full path works. Alternatively, you could add an entry an specify a path with getResultsDir() to have it adjust dynamically... Cheers, Heinrich

Hi, Looking for outsource 3D rendering company. Who do you use for outsourcing 3D rendering? Who do you recommend? Thanks everyone for your recommendation ;)

Hi CJ, I guess I would just create a planar BRep intersection (BRep-based curves) and from this get the area. See attached project... Cheers, Heinrich fishingVessel.cdb

Hi Carlos, Yes. A student license includes the complete functionality of CAESES. See https://www.caeses.com/products/caeses/editions/#students . Cheers, Carl

Hi Carlos, please use a personal message (click on my profile -> message). Out of your last question about starting CAESES in Baseline or in designOfExperiments I assume, that you made a lot of work not with the baseline design. For CAESES each design is its own instance, and they are not connected with each other. So if you doubleclick on a design from a design engine the name of the design on top of the objecteditor gets a green background with a (by default) closed lock. For sure you can make some changes by unlocking the design, but as I said already it will not infect the baseline design. As any design engine starts from the baseline design, this might be the cause for the original issue you reported. If you want to continue working on a specific design from a design engine, you need to make it the baseline-design first: Go inside the design you want to make baseline (doubleclick -> green bar) and "Save Current Design As" a new clean project (without results from the previous design engines). I hope this helps. Best, Carl

Hi Carlos, Please make sure, that you have created an evaluation parameter which takes a value from a result file (@ 5:00 of the video tutorial) and make sure that you have set this parameter as an evaluation in the sobol settings (@6:54). If the parameter has a fix value and no reference like: Runner.getResults().getTable("cd.csv").getElementAt("cd") you may get the Message "There are evaluations that are not influenced by any design variable.". CAESES checks every dependency before running software-connections in an optimization algorithm. It is to save resources. If there is no reference to any value from a resulting file of a software-connection, this application will not be executed. Best, Carl

Hi Carlos, there are two ways to do that: 1) You could write a script that sends the computation to the cluster, waits until it is finished and copies the result back. You can run this as a local computation on your workstation where CAESES is installed. 2) You can install CAESES in your cluster, there is a CRT version, that does not require a GUI (CAESES runs in batch mode). Then you can start design engine runs from the command line. Note, that you have to set up an appropriate software connector before, e.g. if you use a resource manager to submit the computations you need a script that submits the job and waits for the result to come back. Best regards, Hedi

Hi Carlos, the SSH Resource manager is an addon to CAESES which has to be purchased separately. After purchase, the SSH Resource Manager Server must be installed on a host in your network, e.g. the cluster main node. If you have installed this already, please ask your network manager where it is installed. Best regards, Hedi

Hey, I' ve created two feature definitions for importing and exporting of point data. Import: The file is read line by line. To create the point as objects you have to create the feature defintion via execute Defintion (right click). The point data in the csv or txt file has to be separated by white space or comma by default. You will find attached the project, the feature definitions and two example files as a zip file. Best regards Karsten ImportPointData.fdf writeCsv.fdb exampleFiles.zip ReadAndWriteFiles.fdb

The model is unfortunately very bad. There are big gaps between several surfaces. I will see if I can find a repaired one. Best Regards Claus

Hi David, You can display calculated values in the input dialog by defining an additional argument and editing the advanced settings of the feature argument. Here is a video tutorial on how to show result values in the input dialog. Drop down list for input values In addition, you can use String Options to choose an input value from a drop down list. Make sure you switch off the field "Allow Expression" when you use it. By using a "switch" you can define the method you would like to use for your calculations. FString chosenmethod(method) switch (chosenmethod) case "A" echo("using calculation method A") case "B" echo("using calculation method B") case "C" echo("using calculation method C") endswitch Here is the feature definition example that includes the result values in the input dialog and the switch cases with the string options for your reference. DynamicArguments_WithResultField_DropDownListOptions.fdf Have a nice day. Hedi

Hey, I am doing some hydrostatic calculations. I did not find a way to calculate the wetted surface of a boat in the hydrostatic tool. How do you calculate the wetted surface? Thanks.

Hi together, The software CAESES is a CAD and optimization platform. For students and PhD students there are free non-commercial licenses available. In addition, there are low-price offers for start-ups and smaller companies. CAESES can be used for 2D and 3D parametric modeling, see this link for some information about its CAD capabilities. Here are some screenshots: Compared to traditional CAD systems, CAESES is a bit different. It comes with a strict object-oriented approach, i.e. the user sets up dependencies between objects and these dependencies are then kept. This makes it easy to automate the geometry generation process. Here are some features of CAESES: Full 2D and 3D modeling capabilities (NURBS-based)Roughly 20 curve types and 15 surface typesStandard transformations (translation, rotation, scaling)Writing of custom features and functionsBoolean operationsTrimmingFillets between surfacesMorphing functionality for deformation of existing geometrySurface tessellation control through e.g. trimesh objects to create and fine-tune custom STL dataCommon import and export formats e.g. IGES, STEP, PARASOLID, STLIndustry-specific modules for blade and ship designBatch mode for non-GUI (hidden) geometry generation in the background Cheers Joerg LAST UPDATE: NOV 2017

CAESES provides comprehensive functionality for propeller and fan designers so that it can be used as an expert blade design software. Basically, any kind of propeller blade (e.g. boat propeller, aircraft propeller, blowers, fans etc.) for any application can be created with it. CAESES focuses on the variable geometry of blades for design explorations and shape optimization (mostly, together with CFD). Here is a screenshot for an axial blade design, taken from one of the samples that are shipped with CAESES: For general information about modeling of propellers, see the MARINE SECTION. For other rotating machines, please see the TURBOMACHINERY SECTION. 2D PROFILES 2D profiles can be defined by the user. These can be either parametric (e.g. camber curve + thickness distribution) or based on profile data from an air foil data base. There are models available with special definitions such as Wageningen B-Series. NACA curves are also available in CAESES via the menu > curves > naca. When generating the 3D propeller surface, the profile parameters can be changed by means of radial functions for each 2D parameter (e.g. chord, camber, thickness). IMPORT AND EXPORT In order to import or export the blade in a proprietary format, feature definitions can be used which allows you cope with e.g. company-specific ASCII formats. The PFF (Propeller Free Format) is directly supported. EXTERNAL TOOL / CFD AUTOMATION Any preliminary design tool (XFOIL etc) or even CFD packages (in-house, open source, commercial) can be integrated so that a new design can be analyzed within CAESES. BLADE ANALYSIS There is a functionality that can analyze an imported blade surface (given as NURBS) to give you the chord, rake, skew, pitch, thickness and camber distributions. CUSTOMIZATION There is a lot of scripting possible in CAESES so that any specialized design process can be fully transferred into the platform. For instance, if you use Excel sheets for your profile definitions, you can access them through CAESES but also re-implement your methods using the feature definition programming editor. EXAMPLES Some propeller design case studies can be found in this section. If you are interested in drone design, then check out this post here. Here are some videos - the last one I put there only to give you an impression about how the geometry controls can be wrapped and accessed for applying changes, this can be done for all other types of blades as well. Wageningen Propeller ModelPropellerBlade Tip DesignGeometry Changes for an Axial Fan (and a Ship Hull) - Demo Video ONLINE TOOL Finally, check out the new online geometry creator for the Wageningen B-Series. Browser-based, intuitive web app.Allows you to generate typical B-Series propellers with just a few clicks.Requires very little propeller design expertise.The final geometry can be downloaded as STL or STEP file. LAST UPDATE JANUARY 2018 Note that there are FULL FREE ACADEMIC versions of the pro edition CAESES for students and PhD students as well as trial licenses with variable time frames. There are also special editions for small companies, start-ups and freelancers.

Hej Ravi, I don't think that the Torqeedo props are a standard series. Might be that they use some well known section definitions but I don't think they share these information. Designing something that looks roughly like the picture (at least the outlines) will be easy, but you cannot expect to get proper performance this way. What I'd recommend at the very least is, to use a suitable series for the sections (Naca66mod could be a good starting point. Might be that you have to thicken it a little more if you are going for a 3D print), find out the pitch of the original (or, even better the pitch that suits your needs) and then use the propeller sample project that comes with CAESES to adjust chord, skew, pitch etc. distributions along the radius. Cheers, Heinrich

Sorry Christina, if you set up the linesplan, you can export the feature to IGS, that will write out the lines as curves, but not the label.

Hi Nikolas, 1) I can suggest you a work-around; Please check the attached pictures and project; What I have performed is creating a BRep out of the entire exported geometry and then to each BRep I have added an "Remove Faces" operation where I kept only the specified colored surfaces. I have disabled the scope export line inside the fsc file and then included a few lines for the export of the specific surfaces. Please let me know if this resolves your problem. 2) Can you please be more specific about the "cracked" file? Do you refer to the main stl file within which exists the data of the other extracted stl files? Cheers Ceyhan axialfan_sample.cdb

Hi Nicolas, The Export type you require is "STL (Extract Colors)" In CAESES, please create a scope, let's say "02_Export". Then please locate the BRep/s you want to be exported. Please be sure that, the geometrical entities you want to be seperated do have separate colors assigned. Then select the folder, change the file type to "exportStlExtractColors" and provide a file name. Using this procedure, whenever you create an fsc file, the export information will be written automatically. Please let me know if you have further questions. Cheers Ceyhan

Hi Assiouras, it's quite simple: fdb is the file format of the CAESES4.x and older releases, while cdb is the current format of CAESES5.x. There is no backwards compatibility (you can open an fdb in CAESES5 and save it as cdb, but not the other way around), hence the different file type. In addition, anything with an additional "c" indicates a non-commercial license and therefore cannot be opened with a commercial license. Best regards, Heinrich

I have used the Hydrostatic tool with closed trimeshes. The sections displayed below the hull look broken like in the attached example. If I use an open trimesh, the sections look alright. In both cases the calculated values are the same but I am not sure what the broken sections want to tell me. In my current project I only got .stl-files with closed trimeshes of hulls so i can not use the surfaces to do the calculations. surface_trimesh_trimeshclosed.fdbc

Hi, Sometimes diagrams with important data are available only as graphics files (e.g. after scanning from a report or upon exporting from a pdf-file). CAESES / FRIENDSHIP-Framework can be quickly utilized to read off data from diagrams with high accuracy. To do so, import the graphics as an png-file within a "GL Picture Frame" (1st step). Upon setting the scales of abscissa (x-axis) and ordinate (y-axis) (2nd step) you can readily position a point in your diagram and get your x- and y-coordinates (3rd step). (You may want to use such a point to check the level of accuracy.) Furthermore, you can approximate a graph with a curve, say a B-spline curve (4th step) or interpolate it (5th step). Using the curve representation you can "inquire" the y-value for any given x-value (6th step). The attached fdb-project illustrates the work flow for an imaginary speed-power curve. In addition to using CAESES / FRIENDSHIP-Framework to extract data points from diagrams, you can follow the same approach to replicate a lines plan of a boat, yacht or ship, circumventing classic digitization. Offset data are thus produced effectively. Nice side effect is that you can adjust selected points, for instance to improve accuracy of lines remodeling and "repair" apparent outliers. Kind regards, Stefan ExampleDiagram.zip

When working with Meta Surfaces a good way to keep things well organized is using two 3DWindows at the same time (e.g. one as a central widget, the other one as a docked widget below). Using the filter options (points, curves, surfaces and name filter at the bottom of each 3DWindow) you can display only the surface in one window and just the distributional functions in the other. This way you can alter the functions conveniently while observing the immediate effect your changes have on the Meta Surface.

Hi together, If you want to change the rotational direction of a propeller blade (type FGenericBlade), then you can simply switch the orientation. See the attachment for more information. Cheers Joerg

The easiest way to flip the normal of a given surface is by reversing one of the surface directions u or v. In a NURBS/B-Spline surface this can be done with the command .reverse(1,0) or .reverse(0,1). In a Metasurface you can reverse start and end position or you create an image surface and in the u or v domain you enter [1,0] instead of [0,1].

Hi together, Please find attached a parametric model of a centrifugal impeller which was built in CAESES. The project file will probably also be included in version 3.0.11. Note that pretty much everything can be customized in this model and used for manual or automated blade design, such as: Merdional contour (i.e. hub and shroud contour)Profile shape by means of user-defined thickness distributions and beta-angle distributionsFillet shape at the hub region by using a constant factor (BTW: this can also be varied with a function along the blade)Ellipse factor of leading edgeSize of tip gapRotational directionNumber of bladesThickness of casing The splitter blade is completely decoupled from the main blade in terms of the beta-distribution (so this gives more freedom) - but can be linked to the main blade, too. In addition, the model comes with some support geometries for meshing/CFD ("periodic boundaries"). These are automatically adjusted to the blade shapes. The camber lines of the blades are generated from the trailing edge which makes it easier to vary the beta distributions (e.g. fix the TE ends of the blades). There is also a feature definition included which generates the camber line with the leading edge as starting point. When working with the model, switch off all scopes that are "downstream" of where you currently manipulate things. For instance, if you want to change the hub and shroud contour, then set the scopes 02_main, 03_splitter and 04_cake invisible. If you want to change the beta distributions, only visualize the sections that are given in 00_sections. This allows interactive changes to the model with a very short response time. You can also switch off the cake part since it is only there for visualization purposes and CFD pre-processing. Let me know what you think about the model (of course, I hope you'll like it....). Cheers Joerg UPDATE AUGUST 2015: There are new samples directly included in CAESES that you can use for impeller modeling. See my more recent post below. The project files in the attachment do not work correctly for CAESES 4.x versions, we now have much easier ways to design and control hub fillets. UPDATE FEBRUARY 2016: I removed the old project file and added an updated CAESES model to this post. Should work with versions >= 4.0.3. UPDATE FEBRUARY 2017: Note that there are now FULL FREE ACADEMIC versions of the pro edition CAESES for students and PhD students as well as trial licenses with variable time frames. There are also special editions for small companies, start-ups and freelancers. FS_CENTRIFUGAL_IMPELLER.pdf turbocharger_easyuse.fdb

Parametric models are typically built from various geometric or non-geometric entities, e.g. a projection curve depends on the curve that is going to be projected and the surface it is supposed to lay on. In most programs the user creates the desired object first (in this case the projection curve) - and is subsequently asked to supply the necessary objects (surface, curve and possible projection direction) until the configuration is complete. In CAESES/FFW missing information is indicated by a * next to the required attribute and you can set the relationship via drag and drop or typing. However, if you have selected a surface and a curve already when creating the projection curve, they will be automatically associated to the attributes. Note: Whenever the selection set fits to a creator called, the attributes will be set immediately. For every object you will find a list of available creators in the type documentation.

Hi, One of the famous hull forms found in literature is the so-called Wigley hull. It is mathematically defined, see attached formula, and used regularly for tests and validation work. By definition the Wigley hull is a (simple) fully parametric model with beam, draft and height as parameters to control the shape (often normalized by length). A realization of the Wigley hull via a MetaSurface that captures the mathematical formula is given in the attached CAESES project. In addition, some partially parametric modifications are shown, namely, Lackenby type swinging of sections that is realized via a DeltaShift. (Please note that a Generalized Lackenby variation would also be available but was not used here in order to keep the project light.) If you need the hull for your CFD validation work you can use the various exports for panels, offsets, STL, iges etc. More information about ship hull design can be found in the marine section of the CAESES website. Kind regards, Stefan standardWigley.fdb

Hi, please find attached an example for a so-called black box optimization problem. For optimization problems in technical applications it often happens that there is no information on the target function. The research area for the optimization is inside a "black box". So it is very difficult to find the optimum. Time is money. For this reason it is very important to investigate the unknown area quickly and effectively. In order to solve this kind of problem Friendship-Framework contains many optimization algorithms ranging from single-objective strategies for fast and simple studies to multi-objective techniques to investigate a non-linear design space with many local minima and maxima. In the attached file you can try out and compare different algorithms by yourself. Inside the black box (curtain) is a b-spline surface with some local minima and maxima. With the two design variables "usValue" and "vsValue" you can search for a minima by your own. The vertical transparent red surface represents a constraint. Feasible solution can be found only on the right side of the constraint. Sobol, TSearch and NelderMeadSimplex are already performed. Sort the column "objective" within the result table for the smallest value and check the first feasible design. Use the values of "usValue" and "vsValue" from the result table to see where the minimum is found on the b-spline surface (of course you can untoggle the visibility of the blackbox by clicking on the scope "curtain" to see the b-spline surface). Use the feature "optiVisualization" to visualize the way of the optimization algorithm on the surface. Please feel free to try out your own optimization setups. Maybe set the start values "usValue" and "vsValue" on a local minima and see what happens. File for CAESES versions below 4.0.3: optimization.fdb Project file for CAESES 4.1.x: optimization41x.fdb Cheers Matthias

Dear CAESES/FFW Users, I would like to use CAESES with OpenFOAM: - make very simple parametric geometry - use of snappyHexMesh (as mesh generation tool) - use of OpenFOAM (as flow solver) - modify some basic geometry parameters of the geometry - rerun CFD computations with the modified geometry - use of post-processing tools to compare CFD results between configurations I was wondering if someone has already done this kind of exercise and maybe could share it trough the CAESES/FFW forum ? Best regards, Stephane Sanchi.

Please ensure your export folder has the correct setting as shown in my first screenshot from monday. Furthermore, you could have a closer look what is exported by Caeses when updating a parameter in this file path:

Hi Rohan, yes this is possible. You can create a shortest distance line: Best regards Carsten

Dear Rohit, the design variables are used to describe/modify the functions given in 01_blade/functions. You can see how they affect their shape in 3D: You can find detailed information on their exact definitions in the documentations. To get there, just click the little blade icon next to the name of the blade: Best regards, Heinrich

Hi Roopesh, find attached the sample model. best regards Carsten pistonbowl.fdb

Hi Mlysyshyn, For sure you can do that as well. Will create the new configuration and send it once I have some time today. Cheers Ceyhan

Hi Mlysyshyn, Please find attached the modified version. Some modifications I have performed; 1) Within the Runner for the "Local Application" I have selected the AllRun.bat which I have created. Please note that I am not using any arguments. 2) The RunAll.bat executable includes commands within the "C:\OpenFOAM\19.10\cygwin64\Cygwin.bat" executable (lines 4-9) and the path to my script file which is the AllRun.sh (line 9) 3) Finally made a little modification to the script file. The final configuration seems to be working but didn't pay attention to the OpenFoam setup. Cheers Ceyhan Sduct_with_openfoam_2_FSYS.fdbc

Hi Mlysyshyn, Can you please share your project file if it is not confidential? You can also send it to erdem@friendship-systems.com so that I can give a look at your SoftwareConnector setup. Cheers Ceyhan

Hi Mlysyshyn, I can see that the files are are moved to their related locations. Can you please share any console output? Or some OpenFoam logs where the problem can be tracked? Cheers Ceyhan

Hi folks please find attached a Feature Definition for a "Bulbous Bow Shape Analysis" and a Feature Definition which can be used in a CurveEngine for creating a MetaSurface. shapeAnalysis_Bulbous_Bow.fdf bulbous_bow_section.fdf [edited 05.10.14 - tangent analysis included] In order to replace a Bulbous-Bow-IGES-Import by a fully parametric MetaSurface you can use this Feature by execute the following steps: Create a Surface Group including all the IGES-surfacesCreate a new Feature Definition and reload the Analysis-Feature, apply and create the Feature by right click on the Feature Definition>Create FeaturePass the Surface Group to the Analysis-Feature and enter (if necessary) start- and end-position in x-direction of the bulbous bowAdditionally give a number of offsets (30-50 should be a good choice)Run the Feature This will create function curves which can be used to create a MetaSurface. The next steps should be: Re-model the function curves by e.g. FSplineCurvesCreate parameters for some values of the new curves, like start/end position, start/end tangent or area Create a CurveEngineCreate a new Feature Definition, reload the Section-Feature and applySelect the Bulbous-Bow-Section-Feature and pass the new function curves to the EngineAdditionally you can set start- end end-tangent valuesCreate a MetaSurface, select the Curve Engine and set the base positions according to the start- and end-position in x-directionNow you will have a single Metasurface, which is parametric and ready for a design study. Cheers Matthias