# The Magnus Effect Part 1: Simulation Tutorial ⚽ **URL:** \ **Category:** Fluid Flow / CFD\ **Created:** [June 9, 2016, 4:21pm UTC](https://www.simscale.com/forum/t/the-magnus-effect-part-1-simulation-tutorial-soccer/26854 "2016-06-09T16:21:55Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![anon18194957](https://www.simscale.com/forum/letter_avatar/anon18194957/32/5_5575768a8748004e209b776fc1b2916d.png) [@anon18194957](https://www.simscale.com/forum/u/anon18194957)\ **Post date:** [June 9, 2016, 4:21pm UTC](https://www.simscale.com/forum/t/the-magnus-effect-part-1-simulation-tutorial-soccer/26854/1 "2016-06-09T16:21:55Z")
It’s Euro Cup 2016 time which brings to mind an interesting phenomenon…Have you ever seen a football player gracefully curve a ball into the goal? Why does this happen? ### It’s the Magnus Effect! Named after the German physicist H.G. Magnus who experimentally investigated this effect in 1853, the Magnus effect is the phenomenon of the generation of a side-wise force on a spinning spherical solid in a fluid. [Read more…](https://en.wikipedia.org/wiki/Magnus_effect)[1] ### Let’s create a simulation to show the Magnus Effect in action. [https://www.simscale.com/forum/uploads/default/original/3X/c/9/c9b339915bd42e29d7bd3d0b7bc565241e984b84.mp4](https://www.simscale.com/forum/uploads/default/original/3X/c/9/c9b339915bd42e29d7bd3d0b7bc565241e984b84.mp4) **Project Link :** [SimScale Login](https://www.simscale.com/workbench?publiclink=f318b499-259b-4f37-be1d-8990955443a7) Click on this link to directly import the project with the football into your workspace. Then follow the steps below for setting up the simulation. . ### Meshing - In the ‘Mesh Creator’ tab, click on the geometry ‘Football’ - Then, click on ‘Mesh geometry’ button in the options panel. ![](https://www.simscale.com/forum/uploads/default/original/2X/4/41686e648bc902705a3a71ca06d94bed91ac4494.png) - A new mesh operation will be created - rename it as ‘Hex mesh’. Select the last option ‘Hex-dominant parametric (only CFD)’. ![](https://www.simscale.com/forum/uploads/default/original/2X/8/8c2559d194d5a7c4cf579db6ee5b9b85c097acce.png) - Now, scroll down to the bottom and click on ‘Save’. Once saved, new entries will automatically appear under ‘Geometry primitives’ with recommended values. Please note that you have to click on **Save** every time a change has been done to the properties. - Scroll down and check that your settings are as follows ![](https://www.simscale.com/forum/uploads/default/original/2X/0/05255c9251c12b89ec9c3639aa2c241fcc2e4ea6.png) - Now you will see two new items in the project tree: the BaseMeshBox and Material Point ![](https://www.simscale.com/forum/uploads/default/original/2X/b/bb6ef6eafb1e65f7057d4b54ba0187f527715ac9.png) - Please make sure the BaseMeshBox and Material Point have the following coordinates. ![](https://www.simscale.com/forum/uploads/default/original/2X/7/7b1d26347a5b150c59efa0ca898c263ff0c984eb.png) #### Geometry primitive - Next we add a new primitive to include region refinements. It is done by clicking on **Geometry primitive** and selecting **Create new geometry primitive**. ![](https://www.simscale.com/forum/uploads/default/original/2X/d/d6e808c71f70af75e2b9f299fcf98cc62ae4c4a6.png) - Add a new cylinder with the following properties. ![](https://www.simscale.com/forum/uploads/default/original/2X/1/18a851e27cae8d3d5fec18028890e19ba222eb05.png) #### Mesh refinements - Next, we will create 4 ‘Mesh refinements’ by clicking on ‘Add mesh refinement’ in the options panel. ![](https://www.simscale.com/forum/uploads/default/original/2X/5/58b3c5ea13c8e02fb3a853fa0155333e00f1cd50.png) - Add a ‘Surface refinement’ by setting up the options as shown below and clicking on ‘save’. ![](https://www.simscale.com/forum/uploads/default/original/2X/b/bcd2523baed0826a152a1e51c73d7f75eec5bad6.png) - Add a ‘Region refinement’ by setting up the options as shown below and clicking on ‘save’. ![](https://www.simscale.com/forum/uploads/default/original/2X/9/9849c3cedc2bdd1660ce2ca732c555a9ac4ddf9a.png) - Add a ‘Layer refinement’ by setting up the options as shown below. After selecting all the faces from the viewer click on **Add selection from viewer** to select the entities and select ‘Save’. ![](https://www.simscale.com/forum/uploads/default/original/2X/6/6c6ff9cb1a8fa26bb2bfb0c444229e7c21e83329.png) - Add a ‘Feature refinement’ to refine the edges by setting up the options as shown below and clicking on ‘save’. Use a ‘Distance’ of 0.002 and ‘Level’ of 7 ![](https://www.simscale.com/forum/uploads/default/original/2X/a/ad242e8bc38355bfeb06ab49af3f7494a74c9ac8.png) - Now, click back on ‘hex-dominant’ and click on ‘Start’ button to begin the meshing process. The process will begin and the status can be viewed in the lower left corner under ‘Job Status’. ![](https://www.simscale.com/forum/uploads/default/original/2X/c/c9355fd6b480b0bb211f01de28db233deb3f7641.png) The meshing process will take less than 25 minutes to finish. The mesh will automatically load in the viewer once done. ![](https://www.simscale.com/forum/uploads/default/original/2X/b/b84ae8530a0459fda1e348b18095caed4211e58b.png) A cross-section across the domain is as shown. The layers and refinements can be seen as defined. ![](https://www.simscale.com/forum/uploads/default/original/2X/3/3aac6985499690de551dd5441e84263872121661.png) ### Simulation Setup Now to setup the simulation, switch to the ‘Simulation Designer’ tab. - Click on ‘Create new simulation’ in the options panel, give it a relevant name and click ‘Create’ ![](https://www.simscale.com/forum/uploads/default/original/2X/8/806f23054ce9a484be8ff103c14f7521918c43ce.png) - Select the ‘Analysis Type’ options as shown to create an ‘Incompressible steady-state’ with ‘K-omega SST’ turbulence model and click on ‘Save’. ![](https://www.simscale.com/forum/uploads/default/original/2X/d/d31fb6ded0f171a08c08a481bf417e73ff73cf80.png) - After saving, the simulation tree will be generated. We will setup the essential entries required for this simulation. ![](https://www.simscale.com/forum/uploads/default/original/2X/b/b99a1cd0a9bcd905c2cf47c340d27e619a3eb4a3.png) #### Domain - First is ‘Domain’, where we select the ‘Mesh’. Click on ‘Domain’ and select the available mesh and then on ‘Save’. The selected mesh will automatically load in the viewer. ![](https://www.simscale.com/forum/uploads/default/original/2X/0/04fa02488aa854246d43553e404d103647717d9b.png) - Click on ‘Topological Entity Sets’ to name the boundaries of our domain. The boundaries are as shown in the following figures. It has an Inlet and an Outlet surface, the other 4 outer boundaries are marked as walls. ![](https://www.simscale.com/forum/uploads/default/original/2X/3/3d9e9c3caea7e42bfaafb8d8c008ad10957fbb26.png) ![](https://www.simscale.com/forum/uploads/default/original/2X/c/ca751cdc6aca1bafd6ce60e53e7c7bc96a879cb5.png) - Now hide all the outer walls (since we have already named them) and right click in the viewer. Select all the faces and assign it as **Ball**. Now we can define any property to the ball by selecting this entity. ![](https://www.simscale.com/forum/uploads/default/original/2X/8/8aa121802aa5aa26c71a69853ad7b50f291f7cd5.png) #### Model Under model comes the ‘Materials’, ‘Initial conditions’ and the ‘Boundary conditions’. We will go through them one by one. #### Materials - Click on ‘Fluid’ and then on ‘Add Fluid material’ in the options panel. ![](https://www.simscale.com/forum/uploads/default/original/2X/9/9986f997c371b0ee178c48214761e729a3a68868.png) - Scroll down to the bottom and click on ‘Import from material library’ ![](https://www.simscale.com/forum/uploads/default/original/2X/7/7c8fe32efcc518dbdd788e04b1d30ba4769f33e4.png) - Select ‘Air’ and click on ‘Save’ ![](https://www.simscale.com/forum/uploads/default/original/2X/d/d52fca3ac7870fbfe576b13e7802066767f4c142.png) - From the ‘Topological Mapping’ list select ‘region0’ and click ‘Save’ to assign the fluid material to this mesh region. ![](https://www.simscale.com/forum/uploads/default/original/2X/0/0ee2ef3978f1fb227627b530bae8ba80af6ba9f1.png) #### Initial Conditions For the ‘Initial Conditions’ the changes are made in entries an shown in the following figures. Please click the **Save** button every time to save the properties. ![](https://www.simscale.com/forum/uploads/default/original/2X/7/7990753d9ad3b4e8a93ca6bf37d6ddb9f057460a.png) ![](https://www.simscale.com/forum/uploads/default/original/2X/6/6026e6215e84bb0a6143d2153639ebfa274eafeb.png) ![](https://www.simscale.com/forum/uploads/default/original/2X/7/7eac3c71a5d0e4232e91cb0ff0c6341b9d20e50b.png) #### Boundary Conditions - Now add the boundary conditions to the setup. In the sub-tree click Boundary Conditions and select Add boundary condition ![](https://www.simscale.com/forum/uploads/default/original/2X/4/4f6debee71886704902332630b7af102413bbc71.png) **Inlet** - Add a new ‘Velocity Inlet’ boundary condition for ‘Inlet’ BC. This is defined as Fixed value ‘Velocity’ with a value in the x direction of 25 m/s. Click Save ![](https://www.simscale.com/forum/uploads/default/original/2X/1/12061a3cd70e6a373dff8c547fb38e7ac6bb2853.png) **Outlet** - Add a new boundary condition for ‘Outlet’ BC. Define the ‘Outlet’ condition with Pressure outlet with default value. Click Save. ![](https://www.simscale.com/forum/uploads/default/original/2X/c/c16f5ae40003b59db6f8b6082afbd514e2d29345.png) **Ambient** - Add a new boundary condition for the outer walls called as ‘Ambient’. These walls are defined with a ‘Slip’ condition to represent the surrounding. ![](https://www.simscale.com/forum/uploads/default/original/2X/0/0fbc8279ab9706c396a84856dd1f78e5022b11fd.png) **Ball** - Now you can define the spinning condition for the ball, which actually defines the Magnus effect. This is done by giving a rotation to the ball, with an angular velocity of 31.4 rad/s. Please note the negative symbol of angular velocity to account for the direction of rotation. ![](https://www.simscale.com/forum/uploads/default/original/2X/e/e1c4f09b20eccb2ea05f3ff8694907971c1ec518.png) #### Numerics - The following numerics are changed for obtaining a converged solution. Click on **Save** button. ![](https://www.simscale.com/forum/uploads/default/original/2X/2/27274c32c924ad2f8caa2bb5d897e104bb8931c2.png) ![](https://www.simscale.com/forum/uploads/default/original/2X/e/e1ca77f81ae8a14890dc9e89faa764d425ec3e75.png) #### Simulation Control - Click on Simulation Control in the sub-tree and enter the end time as 1000 s with time step of 1. - Click on Details below write control and enter 250. Select the number of cores as 32 and enter 5000 as maximum run time. Click Save ![](https://www.simscale.com/forum/uploads/default/original/2X/3/30fff5aa553c8f97bc6162ef775f567d594be263.png) #### Result Control - We can create some result controls to get additional information out of the simulation. This can be done by selecting **Result control** in the sub-tree and ‘Add forces and moments item’. ![](https://www.simscale.com/forum/uploads/default/original/2X/e/e56d717f7caed4e3fc54556c41b521ae0f4c64c1.png) - The following setting can be maintained to obtain forces and moments acting on the ‘Ball’. ![](https://www.simscale.com/forum/uploads/default/original/2X/3/3345c457061d1ccce3d5fb7be11a1f0f9c0f5a56.png) - Again click on **Result control** and select ‘Add surface data item’. Select as shown below to obtain the y plus values. ![](https://www.simscale.com/forum/uploads/default/original/2X/6/6dedb23d2dbc44b083e52a0435b066a148ad7444.png) #### Create New Simulation Run - Click Simluation Runs on the sub-tree and select **Create new run**. Click on OK ![](https://www.simscale.com/forum/uploads/default/original/2X/9/90bd1a1bedacc706f08d78191771b5922617e6b8.png) - Click on Run 1 and then on **Start** button. This starts computing the simulation run. The simulation runs for 30 mins approximately. Once it is done the status changes to Finished. ### \>[Click here for Part 2 for the Post-Processing Tutorial](https://www.simscale.com/forum/t/the-magnus-effect-part-2-post-processing-tutorial-soccer/28125) **_References_** [1] [Magnus effect - Wikipedia](https://en.wikipedia.org/wiki/Magnus_effect) ---
**Author:** ![anon18194957](https://www.simscale.com/forum/letter_avatar/anon18194957/32/5_5575768a8748004e209b776fc1b2916d.png) [@anon18194957](https://www.simscale.com/forum/u/anon18194957)\ **Post date:** [June 10, 2016, 12:56pm UTC](https://www.simscale.com/forum/t/the-magnus-effect-part-1-simulation-tutorial-soccer/26854/3 "2016-06-10T12:56:07Z")
---
**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:** [June 11, 2016, 11:06am UTC](https://www.simscale.com/forum/t/the-magnus-effect-part-1-simulation-tutorial-soccer/26854/5 "2016-06-11T11:06:19Z")
My results 🙂 ![](https://www.simscale.com/forum/uploads/default/original/2X/0/03a88af9c660550f49e292f49fab6c3026fc0b2f.jpg) Looking forward to discuss the post-processing results! ---
**Author:** ![anon18194957](https://www.simscale.com/forum/letter_avatar/anon18194957/32/5_5575768a8748004e209b776fc1b2916d.png) [@anon18194957](https://www.simscale.com/forum/u/anon18194957)\ **Post date:** [June 12, 2016, 6:50am UTC](https://www.simscale.com/forum/t/the-magnus-effect-part-1-simulation-tutorial-soccer/26854/6 "2016-06-12T06:50:07Z")
Thanks for sharing @jousefm! ---
**Author:** ![akosior](https://www.simscale.com/forum/letter_avatar/akosior/32/5_5575768a8748004e209b776fc1b2916d.png) [@akosior](https://www.simscale.com/forum/u/akosior)\ **Post date:** [June 13, 2016, 6:17am UTC](https://www.simscale.com/forum/t/the-magnus-effect-part-1-simulation-tutorial-soccer/26854/7 "2016-06-13T06:17:59Z")
Hi @anon18194957, I think that this is a very nice test case. I have teo questions to it. When I looked through the OF tutorial cases the conditions for the slip boundaries were ‘slip’ for all fields. In this case you chose slip bc for the Ambient boundary but with the ‘Wall functions’ for the turbulence model fields. The other choice is ‘Zero gradient’. So my first question is what is the impact when selecting wall functions for the slip boundary condition and second is there a possibility to select slip for all fields like in OF tutorial. Best, Andrzej ---
**Author:** ![anon18194957](https://www.simscale.com/forum/letter_avatar/anon18194957/32/5_5575768a8748004e209b776fc1b2916d.png) [@anon18194957](https://www.simscale.com/forum/u/anon18194957)\ **Post date:** [June 13, 2016, 2:02pm UTC](https://www.simscale.com/forum/t/the-magnus-effect-part-1-simulation-tutorial-soccer/26854/8 "2016-06-13T14:02:52Z")
Hi (Andrzej) @akosior, So in this case, we are using ‘slip’ for the velocity condition, ‘zero gradient’ for the pressure, and ‘wall function’ for k and omega. To answer your second question - the main reason for this is that the slip condition has not been implemented for all cases in SimScale (you’ll notice this if you select Type: custom BC). For your first question - I don’t imagine there would be much difference using slip vs wall functions. Were you able to do a comparison of the results? ---
**Author:** ![akosior](https://www.simscale.com/forum/letter_avatar/akosior/32/5_5575768a8748004e209b776fc1b2916d.png) [@akosior](https://www.simscale.com/forum/u/akosior)\ **Post date:** [June 13, 2016, 10:21pm UTC](https://www.simscale.com/forum/t/the-magnus-effect-part-1-simulation-tutorial-soccer/26854/9 "2016-06-13T22:21:15Z")
Hi Anna (@anon18194957), don’t you think that this is a bit misleading that you choose slip bc and you get three different bcs? As in OF slip is derived from basicSymmetry maybe it would be better to leave slip for velocity but set symmetry for the rest of the fields? Best, Andrzej ---
**Author:** ![akosior](https://www.simscale.com/forum/letter_avatar/akosior/32/5_5575768a8748004e209b776fc1b2916d.png) [@akosior](https://www.simscale.com/forum/u/akosior)\ **Post date:** [June 14, 2016, 6:05am UTC](https://www.simscale.com/forum/t/the-magnus-effect-part-1-simulation-tutorial-soccer/26854/10 "2016-06-14T06:05:52Z")
One more thing, @anon18194957. I think that density should be 1.19 not 1.29. Best, Andrzej ---
**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:** [June 14, 2016, 7:10am UTC](https://www.simscale.com/forum/t/the-magnus-effect-part-1-simulation-tutorial-soccer/26854/11 "2016-06-14T07:10:30Z")
Salut @akosior, The density of dry air is **1.29 grams per liter** (0.07967 pounds per cubic foot) at 32° Fahrenheit (0° Celsius) at average sea level barometric pressure (29.92 inchs of mercury or 760 millimeters). • At sea level and at 15°C , the density of air is **1.275 kg/m3**. This is the value of the ISA or International Standard Atmosphere. • At 20 °C and 101.325 kPa, the density of dry air is **1.2041 kg/m3** → STP (standard condition for temperature and pressure) [1] Also the National Institute of Standards and Technology (NIST) uses the temperature of 20 °C (293.15 K, 68 °F) of an absolute pressure of 1atm at a density of **1.2041 kg/m3** * * * Sources: > **[Learn the Weight of a Cloud](https://www.thoughtco.com/how-much-does-a-cloud-weigh-p2-607590)** > > How much does a cloud weigh? Even though clouds float in the air, they have mass, and a lot of it! Here's how to calculate the weight of a cloud. > **[Standard temperature and pressure](https://en.wikipedia.org/wiki/Standard_conditions_for_temperature_and_pressure)** > > Standard temperature and pressure (STP) or standard conditions for temperature and pressure are various standard sets of conditions for experimental measurements used to allow comparisons to be made between different sets of data. The most used standards are those of the International Union of Pure and Applied Chemistry (IUPAC) and the National Institute of Standards and Technology (NIST), although these are not universally accepted. Other organizations have established a variety of other defin... ---
**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:** [June 14, 2016, 7:19am UTC](https://www.simscale.com/forum/t/the-magnus-effect-part-1-simulation-tutorial-soccer/26854/12 "2016-06-14T07:19:54Z")
You probably refer to these two pictures. ![](https://www.simscale.com/forum/uploads/default/original/2X/3/3fb060e42327211db95e1c98b25430f6fbb7a063.png) ![](https://www.simscale.com/forum/uploads/default/original/2X/e/e5c4ceebe9595b00da7b593420c4b5ea33e788f0.png) Also keep in mind that: -------------------- INCOMPRESSIBLE **FREE-STREAM** DEFINITION ------------------ Free-stream density (1.2886 Kg/m^3 (air), 998.2 Kg/m^3 (water)) Source: [Help for Low Speed Analysis -- CFD Online Discussion Forums](http://www.cfd-online.com/Forums/su2/126441-help-low-speed-analysis.html) ---
**Author:** ![akosior](https://www.simscale.com/forum/letter_avatar/akosior/32/5_5575768a8748004e209b776fc1b2916d.png) [@akosior](https://www.simscale.com/forum/u/akosior)\ **Post date:** [June 14, 2016, 7:20am UTC](https://www.simscale.com/forum/t/the-magnus-effect-part-1-simulation-tutorial-soccer/26854/13 "2016-06-14T07:20:22Z")
Hi @jousefm, but for the postpro (calculation of the forces) you have to use the same values that you used in the case. For setting incompressible flow case in OF the only material value you use is kinematic viscosity coefficient. In this particular test case it was taken from the library (look at figure 29.png) for the conditions at which \rho=1.19. ---
**Author:** ![akosior](https://www.simscale.com/forum/letter_avatar/akosior/32/5_5575768a8748004e209b776fc1b2916d.png) [@akosior](https://www.simscale.com/forum/u/akosior)\ **Post date:** [June 14, 2016, 7:21am UTC](https://www.simscale.com/forum/t/the-magnus-effect-part-1-simulation-tutorial-soccer/26854/14 "2016-06-14T07:21:51Z")
@jousefm: You are reffering to SU2 and in this case OF was used. ---
**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:** [June 14, 2016, 7:25am UTC](https://www.simscale.com/forum/t/the-magnus-effect-part-1-simulation-tutorial-soccer/26854/15 "2016-06-14T07:25:42Z")
@akosior: I am a Newbie concerning OpenFoam 🙂 Isn’t SU2 a compressible code? Maybe @anon62721193 can jump in here. ---
**Author:** ![anon18194957](https://www.simscale.com/forum/letter_avatar/anon18194957/32/5_5575768a8748004e209b776fc1b2916d.png) [@anon18194957](https://www.simscale.com/forum/u/anon18194957)\ **Post date:** [June 14, 2016, 8:08am UTC](https://www.simscale.com/forum/t/the-magnus-effect-part-1-simulation-tutorial-soccer/26854/16 "2016-06-14T08:08:34Z")
@akosior and @jousefm - thanks for catching that inconsistency with the density, we’ll update the tutorial to correct that value to 1.19 for both definitions. With regards to the slip bc’s, I’ll pull @Ali_Arafat into the conversation on this since he’s directly involved with the OpenFOAM implementation is SimScale. Again there is a custom BC option where you can directly assign slip, etc. if you so choose. ---
**Author:** ![anon62721193](https://www.simscale.com/forum/letter_avatar/anon62721193/32/5_5575768a8748004e209b776fc1b2916d.png) [@anon62721193](https://www.simscale.com/forum/u/anon62721193)\ **Post date:** [June 14, 2016, 8:17am UTC](https://www.simscale.com/forum/t/the-magnus-effect-part-1-simulation-tutorial-soccer/26854/17 "2016-06-14T08:17:54Z")
Regarding the slip condition, @akosior you indeed have a point. We will add the option to assign slip to all fields, when possible. For the density, if we consider **air at about 25°C** , 1.19 and 1.55e-5 are fitting for density and kinematic viscosity. [Strictly speaking, the only material property required in this incompressible simulation is the kinematic viscosity, i.e. ratio of dynamic viscosity to density. So, you are simulating any fluid that respects this ratio. Other than this, the SU2/OF discussion is not relevant.] ---
**Author:** ![akosior](https://www.simscale.com/forum/letter_avatar/akosior/32/5_5575768a8748004e209b776fc1b2916d.png) [@akosior](https://www.simscale.com/forum/u/akosior)\ **Post date:** [June 24, 2016, 6:22am UTC](https://www.simscale.com/forum/t/the-magnus-effect-part-1-simulation-tutorial-soccer/26854/18 "2016-06-24T06:22:58Z")
@anon18194957 I can see some analogy with your case 🙂 : > **[EDA Software, Hardware & Tools](https://eda.sw.siemens.com/en-US/)** > > Siemens EDA delivers the world’s most comprehensive portfolio of electronic design automation (EDA) software, hardware and services. ---
**Author:** ![TobiasHolzmann](https://www.simscale.com/forum/user_avatar/www.simscale.com/tobiasholzmann/32/350_2.png) [@TobiasHolzmann](https://www.simscale.com/forum/u/TobiasHolzmann)\ **Post date:** [June 24, 2016, 7:15am UTC](https://www.simscale.com/forum/t/the-magnus-effect-part-1-simulation-tutorial-soccer/26854/19 "2016-06-24T07:15:33Z")
Dear all, nice tutorial (I made the Magnus-Effect a few month ago too). In any case I just want to mention that the results will be not too accurate due to the fact that the mesh resolution is not very good, even behind the ball when we have higher gradients (you can really observe that in your video (: ) Cheers. ---
**Author:** ![anon18194957](https://www.simscale.com/forum/letter_avatar/anon18194957/32/5_5575768a8748004e209b776fc1b2916d.png) [@anon18194957](https://www.simscale.com/forum/u/anon18194957)\ **Post date:** [June 24, 2016, 9:30am UTC](https://www.simscale.com/forum/t/the-magnus-effect-part-1-simulation-tutorial-soccer/26854/20 "2016-06-24T09:30:12Z")
@akosior, yep this topic seems to become popular during Euro time 😉 ---
**Author:** ![anon18194957](https://www.simscale.com/forum/letter_avatar/anon18194957/32/5_5575768a8748004e209b776fc1b2916d.png) [@anon18194957](https://www.simscale.com/forum/u/anon18194957)\ **Post date:** [June 24, 2016, 9:34am UTC](https://www.simscale.com/forum/t/the-magnus-effect-part-1-simulation-tutorial-soccer/26854/21 "2016-06-24T09:34:23Z")
@TobiasHolzmann, thanks for your post - We didn’t want to burn too many core hours on a tutorial since it’s a demonstration case 😉 Would you happen to have your version of the project to share? ---
**Author:** ![TobiasHolzmann](https://www.simscale.com/forum/user_avatar/www.simscale.com/tobiasholzmann/32/350_2.png) [@TobiasHolzmann](https://www.simscale.com/forum/u/TobiasHolzmann)\ **Post date:** [June 24, 2016, 9:54am UTC](https://www.simscale.com/forum/t/the-magnus-effect-part-1-simulation-tutorial-soccer/26854/22 "2016-06-24T09:54:53Z")
Dear Anna, I just wanted to mention (as I already wrote) a few things related to accuracy due to discretization and numerics. Unfortunately I am working on terminals with a lot of own settings in OpenFOAM and therefore the case is not build within your simscale software. For me it is only important that people get a feeling about the numerics behind (: Due to the fact that it is only a test case, everything is fine.