# Step-by-Step Tutorial Session 3 - Yaw Angle Study (Part 2) **URL:** \ **Category:** Formula Student/SAE Workshop - 2017\ **Created:** [September 12, 2017, 6:47am UTC](https://www.simscale.com/forum/t/step-by-step-tutorial-session-3-yaw-angle-study-part-2/79720 "2017-09-12T06:47:30Z")\ **Posts on this page:** 1\ **Showing post:** 1
**Author:** ![drodriguez32](https://www.simscale.com/forum/user_avatar/www.simscale.com/drodriguez32/32/14276_2.png) [@drodriguez32](https://www.simscale.com/forum/u/drodriguez32)\ **Post date:** [September 12, 2017, 6:47am UTC](https://www.simscale.com/forum/t/step-by-step-tutorial-session-3-yaw-angle-study-part-2/79720/1 "2017-09-12T06:47:30Z")
## Link to part 1 of the tutorial: [Step-by-Step Tutorial Session 3 - Yaw Angle Study (Part 1)](https://www.simscale.com/forum/t/step-by-step-tutorial-session-3-yaw-angle-study-part-1/79719/1) * * * ## Introduction Welcome to the second part of the step-by-step tutorial for the simulation of a Formula SAE full car with side wind. In this part of the tutorial we will show you the final steps for the simulation setup and we will go over the post processing of the results. Like last session, we will also go through some of the results and what they mean. * * * ## Simulation Setup (Part 2) ### Numerics After defining all the boundary conditions, we will proceed to set up the numerics for our simulation. ![Numerics 1](https://www.simscale.com/forum/uploads/default/original/2X/2/233a11fb4b6a7719e454a6a81fcbec220f91c219.png) Go to **Numerics** and change: 1. **Relaxation factor for field p** , **Relaxation factor for equation U** , **Relaxation factor for equation k** and **Relaxation factor for equation omega** to **0.2, 0.5, 0.5 and 0.5** respectively. 2. Furthermore, under **[p] pressure solver**, change **Absolute tolerance** , **Relative tolerance** and **Number of pre-sweeps** to **1e-8, 0.01 and 1** respectively. ![Numerics 2](https://www.simscale.com/forum/uploads/default/original/2X/1/1f528e8bf736f639e7ea3eff14f4f8415868ee9e.png) Scroll down until **[U] velocity solver** and change: 1. **[U] velocity solver** to **Smooth solver** , **Smoother** to **symGaussSeidel** and **Absolute tolerance** to **1e-7**. Do the same for **[k] Turbulent kinetic energy solver** and **[omega] Specific turbulence dissipation solver** ![Numerics 3](https://www.simscale.com/forum/uploads/default/original/2X/7/7f37f8aefadd57c03f6a10c4ad52c6bccac0bbf5.png) Scroll down to the end and change: 1. Both **Gradient scheme for default** and **Gradient scheme for grad(p)** to **cellLimited Gauss linear** 2. **Laplacian scheme for default** , **Laplacian scheme for laplacian(nu,U)**, **Laplacian scheme for laplacian(nuEff,U)** and **Laplacian scheme for laplacian((1|A(U)),p)** to **Gauss linear limited corrected** 3. Click **Save** to register all of your changes. ### Simulation Control ![Simulation Control](https://www.simscale.com/forum/uploads/default/original/2X/f/f577eb8c50d1387c75c843993cc804cdd25e5fcc.png) For the **simulation control** we will specify the **End time value [s]**, **Number of computing cores** and **Maximum runtime [s]** to **1500, 32 and 50,000** respectively. Also, under _Write Control_ \> _Details_ change the value to **1500**. ### Result Control As the last step before starting our simulation run, we will create result control items in order to obtain graphical data of the results. ![Result control](https://www.simscale.com/forum/uploads/default/original/2X/6/6ed2c5cb16afd1890f44f2066ffc462c8c96de8f.png) Go to **Result Control** and click **+New** next to **Forces and Moments**. #### 1. Front Wing ![FWing](https://www.simscale.com/forum/uploads/default/original/2X/a/ab7aef0e78b2897801529d38916371f4a274bf62.png) A new Force and Moment result control item will be created. Rename it to **FWing** (optional). Change the **Write interval (simulation time steps)** to **5** Select **solid\_0\_FWmainwing** , **solid\_0\_FWEPin** , **solid\_0\_FWEPout** and **solid\_0\_FWflap** , you should see them under **Faces for force calculation**. Click **Save** to register your changes. #### 2. Rear Wing ![RWing](https://www.simscale.com/forum/uploads/default/original/2X/4/48cfbe35246dca14b2e9dce82d2b69d283bfae7f.png) Create a new Force and Moment result control item for the rear wing. Rename it to **RWing** (optional). Change the **Write interval (simulation time steps)** to **5** Select **solid\_0\_RWEP** , **solid\_0\_RWflapa** , **solid\_0\_RWflapb** , **solid\_0\_RWflapc** and **solid\_0\_RWflapd** , you should see them under **Faces for force calculation**. Click **Save** to register your changes. #### 3. Diffuser ![Diffuser](https://www.simscale.com/forum/uploads/default/original/2X/a/ace1836751a3261d1813c6b93af7d836798da802.png) Create a new Force and Moment result control item for the diffuser. Rename it to **Diffuser** (optional). Change the **Write interval (simulation time steps)** to **5** Select **solid\_0\_Diffuser** , you should see it under **Faces for force calculation**. Click **Save** to register your changes. #### 4. Front Wheel ![FWheel](https://www.simscale.com/forum/uploads/default/original/2X/d/da1c46ad6284a4f54849edfe91800c7107edda04.png) Create a new Force and Moment result control item named **FWheel** (optional). Change the **Write interval (simulation time steps)** to **5** Select **solid\_0\_Fronttire** , you should see it under **Faces for force calculation**. Click **Save** to register your changes. #### 5. Rear Wheel ![RWheel](https://www.simscale.com/forum/uploads/default/original/2X/b/b43c191fbc08ecee59a5b924b17a2f3209f60469.png) Create a new Force and Moment result control item named **RWheel** (optional). Change the **Write interval (simulation time steps)** to **5** Select **solid\_0\_Reartire** , you should see it under **Faces for force calculation**. Click **Save** to register your changes. #### 6. Body ![Body](https://www.simscale.com/forum/uploads/default/original/2X/9/93da72d3580ce4613e5196976ecc354ce0daef94.png) Create a new Force and Moment result control item named **Body** (optional). Change the **Write interval (simulation time steps)** to **5** Select **solid\_0\_body** , **solid\_0\_Frontsusp** , **solid\_0\_Rearsusp** , **solid\_0\_Barre** , **solid\_0\_Sidepood** , **solid\_0\_Frontur** , **solid\_0\_Radsupport** , **solid\_0\_Rearur** and **solid\_0\_Driver**. You should see them under **Faces for force calculation**. Click **Save** to register your changes. ### Simulation Run Once all the above steps are defined, we will proceed to create our first simulation run. ![Simulation run](https://www.simscale.com/forum/uploads/default/original/2X/4/4a5e372fb4374d1a1a0c6ba9c3920eb0d227825a.png) Go to **Simulation Runs** and click on **+New**. A window will pop up, give a reasonable name to the run e.g. **Run-conf-Yaw** in this case (optional) and click **Create** in order to create a new run. After the run is created, click **Start** to start the created run. The simulation run can take up to **~190 minutes (~3 hrs.)** * * * ## Post-Processing ![Post processing](https://www.simscale.com/forum/uploads/default/original/2X/c/c98322b2bfd0dee895498dc87d2654d63f81d239.png) Once in Post-Processor, click on Solution fields under Run-Conf-Yaw in order to load the results in viewer. Due to full car model that we are using, it can take up to 20 minutes to load the results in to the viewer. In order to reduce the time of loading the results we suggest for you to select only **U** and **P** under the **Property panel** and **Cell Arrays**. For further instructions about how to post-process your results please follow the same steps detailed in the exercise in Part 2 of Session 2. [Step-by-Step Tutorial Session 2 - Full Car Aerodynamics (Part 2)](https://www.simscale.com/forum/t/step-by-step-tutorial-session-2-full-car-aerodynamics-part-2/79350) * * * ## Homework Submission For your homework, your task is to investigate the full car running in a straight line at 20 m/s with side wind. You will have the same model we used for the last session, so you will setup _porous media_, _MRF (rotating) zones_, _rotating walls_, and the flap angle will be _0_ degrees. Think about how this setup differs from the previous one and think about the impact of the side wind on the performance of the car and the flow behavior around it. The step-by-step tutorial below contains all of the steps for setting up the simulation in SimScale and visualizing the results. > We’ve made an update to the platform and the sharing procedure has changed. Please go to the following link to see how to get a sharing link for your project: > [New Sharing on SimScale](https://www.simscale.com/forum/t/sharing-a-project/242) **Homework Deadline** : October 17th, 11:59 pm CEST #### [Click Here to Submit your Homework](https://marketing.simscale.com/acton/form/14483/00d3:d-0001/1/-/-/-/-/index.htm) * * * ## Results #### Animation: Velocity [m/s] - X Normal #### Animation: Velocity [m/s] - Z Normal ![1](https://www.simscale.com/forum/uploads/default/original/2X/d/d6adc6452f5e12c69df010eea3060a1d5035821a.png) ![2](https://www.simscale.com/forum/uploads/default/original/2X/b/b7b79187e5eb529b1b801bbfddfc55091ee8103b.png) ![3](https://www.simscale.com/forum/uploads/default/original/2X/c/caf4eeb12eebbaa2540574b56e7363b8c6c1a7fb.png) ![4](https://www.simscale.com/forum/uploads/default/original/2X/f/f10a4532d297a46b1b5231398d668aa6bb0e7291.png) ![5](https://www.simscale.com/forum/uploads/default/original/2X/f/f10fea830e80ca94cd13292fccfae22573bdc347.png) ![6](https://www.simscale.com/forum/uploads/default/original/2X/5/50722b6166c61f6a4c9104f6a55ca7ac9cb62376.png) --- _[View the full topic](https://www.simscale.com/forum/t/step-by-step-tutorial-session-3-yaw-angle-study-part-2/79720)._