1. My Road to Supercomputing Holly Krutka The University of Oklahoma

2. Research Background  Using a computational fluid dynamics (CFD) package Fluent to simulate air flow  The air flow is related to the melt blowing process of polymers  Chemical engineer  NOT A COMPUTER SCIENTIST!!!

3. Examples of Melt Blowing Dies

4. Why Use CFD?  Experiments had already been completed  There is no affordable way to include the polymer in the air flow and take experimental measurements  To be on the cutting edge of research in our field  FAST AND CHEAP!!!

5. How Fluent Works  Make a computational domain  Split domain up into finite volumes  Set boundary conditions  Set model parameters  Fluent solves the continuity equation, momentum equations, ect.  Analyze simulation results

6. What can be gained from CFD?

7. Undergraduate Research  2D simulations  Symmetrical  Isothermal initially  Grid cells were small  About 100,000 cells per grid  Using a single processor on a lab computer  Simulations required between 2-6 days to finish

8. Graduate Research  Simulations become much more complex  Non-isothermal  3D  700,000 – 2,000,000+  Including polymers  Time dependent simulations  Lots of simulations to run…and only two processors?!?!?!?

9. Supercomputing  CFD program is actually designed to run on a supercomputer  OU has a great supercomputing program  One problem….still NOT a computer scientist  YOU DON’T NEED TO BE!

10. Using Sooner  CFD package was loaded on to Sooner (Brandon George, OSCER Manager of Operations )  Started using sooner.oscer.ou.edu (IBM p690, 32 POWER4 1.1 GHz CPUs, 32 GB RAM -- now decommissioned)  Use Secure Shell to move my simulations to Sooner  Wrote a simple script file (with help) to run the simulations  Submit the simulations to the queue and wait

11. From Sooner to Topdawg  Fluent loaded on to Topdawg (Brandon George)  Later transitioned to topdawg.oscer.ou.edu (Dell Xeon cluster,1024 Xeon 3.2 GHz CPUs, 2176 GB RAM) Simulations are submitted in a queue, similar to Sooner  Great improvement on speed Desktop → Sooner → Topdawg

12. Advantages  Using more processors at a time (4 – 8)  Much faster  More simulations at once  Much more stable  My desktop computer is free to work

13. Conclusions  You do not need to be a computer scientist to use OU’s supercomputing resources  Utilizing OSCER has greatly improved both the quality and quantity of my PhD research

14. Questions?