# Session 3 Homework: Aerodynamics of an Aircraft - Part I Meshing **URL:** \ **Category:** CAD & Meshing\ **Created:** [July 27, 2016, 1:37pm UTC](https://www.simscale.com/forum/t/session-3-homework-aerodynamics-of-an-aircraft-part-i-meshing/34949 "2016-07-27T13:37:22Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Ali\_Arafat](https://www.simscale.com/forum/user_avatar/www.simscale.com/ali_arafat/32/153_2.png) [@Ali\_Arafat](https://www.simscale.com/forum/u/Ali_Arafat)\ **Post date:** [July 27, 2016, 1:37pm UTC](https://www.simscale.com/forum/t/session-3-homework-aerodynamics-of-an-aircraft-part-i-meshing/34949/1 "2016-07-27T13:37:22Z")
## Aerospace Workshop Session-3 Homework ## Recording [![](https://www.simscale.com/forum/uploads/default/original/3X/0/0/0061dbd279cc6195e2a9bc5cf5f24112b0f7ed04.jpeg "Aerospace Workshop feat. EUROAVIA: Compressible Aerodynamics of an Aircraft") ](https://www.youtube.com/watch?v=kcCuSpomarc) ## Homework submission Submitting all three homework assignments will qualify you for a free Professional Training (value of 500€) as well as a certificate of participation. Homework 3 - Deadline Date 07.08 at 12:00pm [Homework Submission Form](https://marketing.simscale.com/acton/form/14483/007c:d-0001/0/-/-/-/-/index.htm) ## Exercise The task is to perform the aerodynamics simulation of an Aircraft model at different flow velocities and 2 different setups. First case is with free domain boundaries and the second is close to the ground. The figure below describes briefly the two cases: ![](https://www.simscale.com/forum/uploads/default/original/2X/b/b086c8a79f18208a132866a2c5ff6f35b883e304.png) \_\_ ![](https://www.simscale.com/forum/uploads/default/original/2X/2/2b175575f7b162e7bac153b1f5ad7d210dba252d.png) The table below gives the flow velocities for the different setups : ![](https://www.simscale.com/forum/uploads/default/original/2X/a/a6e40947aef910a62904f2ccd57c92e1eb88dc2d.png) **Note: For cases with M=0.35, Velocity Ramping is required via a file upload which is explained later in the simulation setup.** For these cases we will use the **“Hex-Dominant Parametric”** meshing operation which provides full functionality to mesh complex geometries. The Tutorial below will provide detailed steps on how to use each meshing feature to get a well resolved mesh. ## Step-by-Step **Import the project by clicking the link below.** ( Crtl + Click to open in a new tab ) [Click to Import the Homework Project](https://www.simscale.com/workbench?publiclink=d58ee578-19ee-448b-9b2e-5509869f3b56) **Once the project is imported, the workbench is automatically opened. Then follow the steps below for setting up an incompressible flow simulation**. ### Mesh-1 (Free domain boundaries) ### Geometry ![](https://www.simscale.com/forum/uploads/default/original/2X/b/b817c31d25fc092124d37d2706b973009061515e.png) **Note: The imported geometry has pre-created ‘Topological sets’ for some essential geometry faces. These sets will be later used for mesh refinements.** The created Sets are shown in the figure below, you can click to highlight the set in red. ![](https://www.simscale.com/forum/uploads/default/original/2X/9/91884bb1b3b2fad13ac73cce02c57c716c9456b7.png) ### Creating a Mesh - Select the geometry and click on **‘New Mesh’** button to create a new mesh operation as shown. ![](https://www.simscale.com/forum/uploads/default/original/2X/d/daa48263a0494df3e54e3573ed0049b13174f4b9.png) #### **Main Settings** - In the Main Settings , select **“Hex-Dominant Parametric (CFD)”**. Then specify the following parameters and click **Save.** **Number of cells in X-direction: 21** **Number of cells in Y-direction: 112** **Number of cells in Z-direction: 90** **Number of computing processors: 16** ![](https://www.simscale.com/forum/uploads/default/original/2X/c/c118092998397ffefc9adfd9a6b48f5ebc1d57e0.png) - After saving the tree is extend with 2 new entries, called **‘BaseMeshBox’** and **‘Material Point’** which must be defined. ![](https://www.simscale.com/forum/uploads/default/original/2X/a/a2fd2a4760552f1f7358c93a10d98419fcccb19a.png) #### **Geometry Primitives** **Base Mesh Box** The **‘Base Mesh Box’** defines the outer flow domain boundaries. This must be significantly larger for external flow. Enter the values as shown and click Save. **Min X= 0.001** **Min Y= -450** **Min Z= -525** **Max X= 175** **Max Y= 450** **max Z= 350** ![](https://www.simscale.com/forum/uploads/default/original/2X/8/835e6608a48a44cc7de2f6ce227a85d595c3b1cd.png) **Material Point** The **‘Material Point’** specifies the region that will be meshed. So in this case the point must be out side the aircraft body. Enter the values as shown and click Save. **Center X= 16.1** **Center Y= 10.7** **Center Z= -16.3** ![](https://www.simscale.com/forum/uploads/default/original/2X/8/896a09b938176a263e6ac365c3c2d2a43bb69fc2.png) #### **_Further primitives_** - We will create 4 entities that will be used for mesh region refinements later in the meshing setup. - To create a New entity, click on **‘Geometry Primitives’** and then the **‘New’** button on top to select a **‘Cylinder’** entity. ![](https://www.simscale.com/forum/uploads/default/original/2X/6/6b9cc6d2be044a8c9017f4ef5dc5e909521e63a2.png) The table details the parameters for the 4 cylinder entities that are shown in the figures below. ![](https://www.simscale.com/forum/uploads/default/original/2X/c/c40fb9698d929b278a77eee6a2784843613fed87.png) . **Cylinder Outer** ![](https://www.simscale.com/forum/uploads/default/original/2X/d/d28b22dbe7a78d771eddd218838dae7184bc4d03.png) **Cylinder Inner** ![](https://www.simscale.com/forum/uploads/default/original/2X/d/d952c4196ae142e253cb1ecb57bd3a14317ab3be.png) **Wing tip** ![](https://www.simscale.com/forum/uploads/default/original/2X/f/ff3cc4a0142bdd40302c7fe141111e26fb9b2a00.png) **Fin tip** ![](https://www.simscale.com/forum/uploads/default/original/2X/7/70e6b57db208868bb84550e29f4e3b3e4a84985c.png) #### **Mesh Refinements** We will now add the necessary mesh refinements for the previously created geometry sets and the geometry primitives. - Click on **‘Mesh Refinements’** and click **‘New’** button to add a refinement. ![](https://www.simscale.com/forum/uploads/default/original/2X/f/fa9130754a964908f568b743071a3e8b6dcbc410.png) #### Surface refinements - This refinement will used to refine the surfaces for the complete solid geometry. Select the settings as follows and click **Save.** **Name: All Surfaces** **Type : Surface refinement** **Level Min : 6** **Level Max : 7** **Assigned entity Type: Volume** **Name: ‘solid\_0’** ![](https://www.simscale.com/forum/uploads/default/original/2X/2/269e478aae747adb3f647eca024f651841d3e9e5.png) . - This refinement will used to refine the surfaces for the existing **face Set** named **‘Wing-Fins’.** Select the settings as follows and click **Save.** **Name: Surf- Wing-fins** **Type : Surface refinement** **Level Min : 7** **Level Max : 7** **Assigned entity Type: Face sets** **Name: ‘Wing-Fins’** ![](https://www.simscale.com/forum/uploads/default/original/2X/4/4a868d4fc2ed533f77a81c5f30054a897cfefe8a.png) . - This refinement will used to refine the surfaces for the existing **face Set** named **‘Thin-edges’.** Select the settings as follows and click **Save.** **Name: Surf - Thin edges** **Type : Surface refinement** **Level Min : 10** **Level Max : 10** **Assigned entity Type: Face sets** **Name: ‘Thin-edges’** ![](https://www.simscale.com/forum/uploads/default/original/2X/4/468cba5075c0a4c8af545135796de8209b7687c2.png) . - This refinement will used to refine the surfaces for the existing **face Set** named **‘Fillets’.** Select the settings as follows and click **Save.** **Name: Surf-fillets** **Type : Surface refinement** **Level Min : 9** **Level Max : 9** **Assigned entity Type: Face sets** **Name: ‘Fillets’** ![](https://www.simscale.com/forum/uploads/default/original/2X/6/67538e827c9a7e56f64edb496e48f477e0022a63.png) #### Region refinements These refinements will refine the volume mesh. We will create 3 region refinements and assign them the previously created geometry primitives. - So create a new **‘Mesh Refinement’**. - and enter the settings as follows: **Name: Reg-Tips** **Type : Region refinement** **Mode : Inside** **Distance : 1** **Level : 9** **Assigned geometry primitives: Wing-tip , Fin-tip** ![](https://www.simscale.com/forum/uploads/default/original/2X/1/1d6feff64b0637a5ba4ae3decfc26c2a922dab10.png) . **Name: Reg-Inner** **Type : Region refinement** **Mode : Inside** **Distance : 1** **Level : 3** **Assigned geometry primitives: Cylinder-inner** ![](https://www.simscale.com/forum/uploads/default/original/2X/1/15c16815eee0ca3efa0cddbdb4a5298183c94817.png) . **Name: Reg-Inner** **Type : Region refinement** **Mode : Inside** **Distance : 1** **Level : 2** **Assigned geometry primitives: Cylinder-Outer** ![](https://www.simscale.com/forum/uploads/default/original/2X/4/49d961c9bcabb4fbd770f863666b77c69f32f816.png) #### Feature refinement The feature refinement will refine near edges. This is important to capture sharp corners. - So Add a New **‘Mesh Refinement’** , and choose **Type** as **‘Feature Refinement’**. Give a **Distance of 0.25 and a Level of 8.** ![](https://www.simscale.com/forum/uploads/default/original/2X/4/496ee81a7eda2db306a77ecd67ee287a65526d11.png) #### Layer refinement The layer refinement is important to capture the boundary layer near the wall. This will create layer cells following the surface curvature near the walls. - So Add a New **‘Mesh Refinement’** , and choose **Type** as **‘Layer Refinement’**. Change **‘Number of layers’ to 3** and **‘minThickness to 0.001’** - Then to select all the surfaces, click the **‘select’** button in the viewer tool bar [A], click **‘Select all’** [B] and then click **‘Add selection from viewer’** button [C] in the settings panel and click **Save**. ![](https://www.simscale.com/forum/uploads/default/original/2X/9/9a403f5773b284d2fa12897c42957c12fd8c031c.png) #### **Some Advance settings** Lastly, we will change a few parameters in the **Advance Settings** by clicking on the mesh operation and scrolling in the settings panel as shown in figures below. This will help to get a good quality mesh for a complex geometry. - **Only the highlighted parameters need to be changed to the shown value.** ![](https://www.simscale.com/forum/uploads/default/original/2X/9/9d4cad35dfe3010e31261f8d92a11d5fbf805bb6.png) ![](https://www.simscale.com/forum/uploads/default/original/2X/8/813f42c7108e4a2ac0479ab07935e597bc6314e5.png) ![](https://www.simscale.com/forum/uploads/default/original/2X/c/c5d2c9dd3f751c239694a595a8a2db31a756197f.png) **Start the Meshing Operation** Finally, click **Save** then to Start the mesh operation click on the **Start** button at the top. ![](https://www.simscale.com/forum/uploads/default/original/2X/7/7e38c760b7a91e6183bc09a6e82a320d4302d1e4.png) ### Mesh-2 (close to the ground) - For the second mesh, start by making a ‘Duplicate’ of the first mesh by **right-clicking** and selecting **‘Duplicate’**. ![](https://www.simscale.com/forum/uploads/default/original/2X/5/5bf183fb8702f5f4ae8c54e6e024e9a73c53b175.png) - Next, change the **‘Base Mesh Box’** dimension of **‘Min Y’** to **-3.65** and click **Save**. - As the domain is now shorter in the Y-direction, we will adjust the base cell size under the **‘Main Settings’** by changing **‘Number of cells in Y-direction’ to 57**. ![](https://www.simscale.com/forum/uploads/default/original/2X/e/e6ff57842c7747e0dfc926e5b0ed8041174494be.png) - Lastly, we will **add a New mesh refinement** of type **‘Bounding box layer addition’** to add a layer mesh to the ground floor. So enter the following values: **Bounding box face : Y Min** **Number of layers : 4** **expansion ratio : 1.3** **finalLayer Thickness : 0.5** **minThickness : 0.01** ![](https://www.simscale.com/forum/uploads/default/original/2X/9/96681f7843660e70f23f06c244a63f0806c703e2.png) - That’s all. Once done click the **‘Start’** button to begin the meshing operation. **There will be a warning message saying that the previous mesh result ( the duplicated one) will be deleted. That is OK, so just click yes and continue.** #### **Once done with the Meshing, follow [Homework Part-II](https://www.simscale.com/forum/t/session-3-homework-aerodynamics-of-an-aircraft-part-ii-simulation-setup/34947) (Click) for the Simulation Setup.** ---
**Author:** ![Ali\_Arafat](https://www.simscale.com/forum/user_avatar/www.simscale.com/ali_arafat/32/153_2.png) [@Ali\_Arafat](https://www.simscale.com/forum/u/Ali_Arafat)\ **Post date:** [July 27, 2016, 1:37pm UTC](https://www.simscale.com/forum/t/session-3-homework-aerodynamics-of-an-aircraft-part-i-meshing/34949/2 "2016-07-27T13:37:30Z")
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**Author:** ![SamPrabhu1](https://www.simscale.com/forum/user_avatar/www.simscale.com/samprabhu1/32/4813_2.png) [@SamPrabhu1](https://www.simscale.com/forum/u/SamPrabhu1)\ **Post date:** [July 28, 2016, 1:13pm UTC](https://www.simscale.com/forum/t/session-3-homework-aerodynamics-of-an-aircraft-part-i-meshing/34949/3 "2016-07-28T13:13:33Z")
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**Author:** ![julien\_venture](https://www.simscale.com/forum/letter_avatar/julien_venture/32/5_5575768a8748004e209b776fc1b2916d.png) [@julien\_venture](https://www.simscale.com/forum/u/julien_venture)\ **Post date:** [April 27, 2018, 9:29am UTC](https://www.simscale.com/forum/t/session-3-homework-aerodynamics-of-an-aircraft-part-i-meshing/34949/4 "2018-04-27T09:29:38Z")
Hello, I am doing the mesh for this exercise. However the advanced setting has changed between the version of the tutorial and the one I’m using. As a result, I do not know what to change and how. Can you help me ? Thank you in advance Julien ---
**Author:** ![jousefm](https://www.simscale.com/forum/user_avatar/www.simscale.com/jousefm/32/34908_2.png) [@jousefm](https://www.simscale.com/forum/u/jousefm)\ **Post date:** [April 27, 2018, 10:23am UTC](https://www.simscale.com/forum/t/session-3-homework-aerodynamics-of-an-aircraft-part-i-meshing/34949/5 "2018-04-27T10:23:43Z")
Hi @julien_venture! Can you tell me where exactly you have problems? If you cannot find a parameter that has been added later on I would leave that as default and try meshing it. Another option would be to share your project with me, I will adapt the parameters this evening and share the mesh with you again (which is not super efficient tbh) 😉 Cheers! Jousef ---
**Author:** ![julien\_venture](https://www.simscale.com/forum/letter_avatar/julien_venture/32/5_5575768a8748004e209b776fc1b2916d.png) [@julien\_venture](https://www.simscale.com/forum/u/julien_venture)\ **Post date:** [April 27, 2018, 1:44pm UTC](https://www.simscale.com/forum/t/session-3-homework-aerodynamics-of-an-aircraft-part-i-meshing/34949/6 "2018-04-27T13:44:57Z")
Hi @jousefm I’m stuck on the part named “Some Advance settings” in the tutorial. Indeed the interface is different. Here is the link of the project : [SimScale](https://www.simscale.com/projects/julien_venture/aerospace_workshop-_session_3_homework_1/) ---
**Author:** ![jousefm](https://www.simscale.com/forum/user_avatar/www.simscale.com/jousefm/32/34908_2.png) [@jousefm](https://www.simscale.com/forum/u/jousefm)\ **Post date:** [April 28, 2018, 9:27am UTC](https://www.simscale.com/forum/t/session-3-homework-aerodynamics-of-an-aircraft-part-i-meshing/34949/7 "2018-04-28T09:27:01Z")
Hi @julien_venture! Currently running the mesh and will share it with you as soon as it ready! 👍 Cheers! Jousef ---
**Author:** ![jousefm](https://www.simscale.com/forum/user_avatar/www.simscale.com/jousefm/32/34908_2.png) [@jousefm](https://www.simscale.com/forum/u/jousefm)\ **Post date:** [March 20, 2020, 7:00pm UTC](https://www.simscale.com/forum/t/session-3-homework-aerodynamics-of-an-aircraft-part-i-meshing/34949/9 "2020-03-20T19:00:56Z")