This article describes the workflow and settings/considerations to run Star-CCM+ CFD software on the Nimbix cloud.
To access Star-CCM+ on Nimbix platform, the following steps are required:
1. Select the desired Star-CCM+ release from the Compute dashboard.
NOTE: If the option is not available in the first-page menu, press on “More” at the bottom of the page as shown in the image below:
2. A splash window will open. Select the Simcenter STAR-CCM+ option as shown below:
3. The Nimbix Cloud set-up screen opens and here you must choose some of your settings by clicking on the tabs on the top of the window (General, Optional, etc) one tab at a time.
UNDER GENERAL TAB
1. Under Machine type when you click on the caret on the right, you can select the type of machine you want to run your job on. The decision on machine type selection is based on the size and complexity of your model and cost associated with the machine type (some machines will have higher RAM, others will only run the job on single CPU, others will have better graphics and therefore higher cost, etc).
NOTE: When running interactive based applications, you’ll find that selecting an NC9 or any NC* machine types should offer significant visual performance over not selecting an NC machine type. By selecting an NC machine, this places a GPU on your head-node, and offers better visual performance. Another thing to keep in mind, is that when running interactively you can use a web-browser, or in some cases for large models or you might consider using RealVNC.
2. Select the number of cores:
The machine type you selected in the previous step, will dictate the increment in the number of cores that you can choose/select. For a very simple and small model, you can leave default selection, which in this case would be “16” or move the scroll bar to the desired number of cores or simply type over “16” the number of cores you wish to run your job on (we left it default in this case):
NOTE: Do not confuse number of cores with number of nodes (nodes represent the number of increment of cores that you selected. In the example above, 1 node represents 16 cores, 2 nodes correspond to 32 cores).
3. Enter the POD license key (need valid license to run Star-CCM+ on NIMBIX). The POD license key in this example is NOT a valid POD license key.
UNDER OPTIONAL TAB
1. Assign a JOB LABEL (give a name that will help you keep track on your running jobs. For example, My_StarCCM_Project):
2. Leave blank the wall time limit, Simulation database (for a new simulation), and the IP address. The Window size needs to be kept as default.
UNDER STORAGE TAB
Select vault type: Default vault is “drop.jarvice.com”.
The “drop.jarvice.com” vault is recommended for small to medium size jobs, such as Start-CCM+ simple projects, simple linear Mechanical Analysis projects, and simple Fluent projects (not multi-phase). For any complex and computationally heavy jobs, and where partitioning the job over number of cores becomes challenging, the PREMIUM vault is strongly recommended. The PREMIUM vault can be found under the drop down menu under “Select Vault” tab (NOTE: requires subscription and extra monthly payment to have access to PREMIUM vault).
Before submitting your job for running, you can preview your settings under the PREVIEW SUBMISSION tab.
Start your NIMBIX job by clicking on the SUBMIT button.
After STAR-CCM+ has been successfully launched, you should be able to see the STAR-CCM+ in the preview and can access the window by clicking on it (you can see details on the number of nodes, some information regarding memory, etc):
Click on the preview window in your browser to open STAR-CCM+ in a new window/tab. You are now inside the STAR-CCM+ environment.
STAR-CCM+ SETUP AND SOLUTION ON NIMBIX CLOUD (abbreviated steps)
Start a New Simulation: File to New or click on “New File” to start a new simulation:
NOTE: Verify the proper process options (Parallel on Local Host) and the Compute Processes (should match the number of cores selected) as set-up in the GENERAL tab during cloud set-up.
Set up your simulation (preprocessing) using CAD or primitives, boundary conditions, solvers, etc. Consult Star-CCM+ user-guide for additional information on how to set up your analysis. Save your work periodically.
Solve your model clicking on “Run” button once the model is properly set-up.
Monitor your residuals in the “Residuals” scene during solve:
NOTE: You can also monitor your utilization (to see how much memory is utilized and whether the number of nodes you selected are in fact used). Click on the Detailed Metrics button:
Post Process (visual representation of your field variables) your solution using scalar, vectorial, streamline scenes.
Save and Exit (File to Exit option) once post-processing is completed:
NOTE: A log file can be accessed post run (usually also sent as an attachment to the e-mail associated with the current user or downloadable from the job history).