# Presentation: 193751

## Multiagency Coordinating Committee for Combustion Research:Next Steps in Using Combustion Cyberinfrastructure

- Phil Westmoreland                                                                Program Director, Combustion, Fire, and Plasma Systems; NSF/ENG

**MACCCR Workshop on Advancing Cyberinfrastructure, San Diego CA, March 28-29, 2007**

- Multiagency Coordinating Committee for Combustion Research:DoD - DOE - FAA - NASA - NIST - NSF

## Workshop agenda

- Wednesday, March 28, 2007, 1:30-5:30pm
- 1:30pm: Review of Workshop context, agenda, and goals
- 1:50 pm: Perspectives from the TNF Workshop, Rob Barlow, CRF
- 2:35pm: PrIMe – A Virtual Organization; Phil Smith (Utah), Michael Frenklach (Berkeley), Greg Smith (SRI)
- 3:20pm: BREAK
- 3:40pm: Developing Cyberinfrastructure for Data-Oriented Science and Engineering; Fran Berman, Director, SDSC
- 4:20pm: Insights from the Pittsburgh Combustion Simulation Workshop;  Geo Richards, NETL
- 5:00-5:30pm: Open Discussion
- Thursday, March 29, 2007
- 8:00am: Panel-Oriented Discussion of Opportunities and Action Items
- 9:30am: Breakout sessions to identify needs
- 10:30-11:30am: Recap of breakout sessions; Identification of Action Items

## What is cyberinfrastructure - and what isn’t it?

## Combustion research has been a leader in using cyber resources for modeling.  For example: 

## Automating the Generation of Detailed Chemical MechanismsBill Green (MIT) - CBET-0312359 

- Complicated chemical mechanisms abound in manufacturing, biology, environment, and _energy & pollutants from combustion_.
- Ultimately, they are sets of individual reactions.

- Project goal: To automate construction & solution of combustion simulations.
- With XML data formats, maintain a large software package, used / modified by many researchers.
- Include unambiguous documentation of simulation assumptions.
- Generate simulation confidence limits along with the predictions.

**Notes:**
We have developed hierarchical functional group trees and rate estimation rules for 32 different types of chemical reactions so far.
* With 32 reaction familes and about 700 functional groups you definitely need a GUI to keep track of all the rate estimates. Here is a screen shot. If you are interested, I can show you a demo during the break.
* We use the rate-based algorithm of Susnow et al. to determine which reactions and species to include in the kinetic model. It works like this: initially you start with a small mechanism, and at each iteration you add the minor byproduct that is estimated to be formed at the highest rate, as long as its rate is high enough to be considered numerically significant. Then you generate all the secondary byproducts that result from the reactions of this important byproduct. The algorithm stops when none of the byproducts are formed at a significant rate, by this formula. 
* Software needs to be modified/extended often as chemistry understanding improves.     Many different groups will contribute.     So far ZERO model-construction programs suitable for broad distribution.......Software maintenance is Big Problem     New data model helps a lot, because most changes will be made in data, not software.
* Figure shows the data (of the new data model). (In prior software using the 20th century data model, all the information and relationships in the database shown was hard-coded into the software, making an incredible mess inside the program that no one could update or even debug effectively).

## (2) Using Full Chemistry in Large-Scale Simulations (Turbulent Combustion) Pope, Chew, Guckenheimer, Vavasis, & Givi (Cornell & Pittsburgh)- CBET-0426787 

- (2) Using Full Chemistry in Large-Scale Simulations (Turbulent Combustion) Pope, Chew, Guckenheimer, Vavasis, & Givi (Cornell & Pittsburgh)- CBET-0426787

- Using full mechanisms by brute force is not practical to model chemistry in complicated environments.
- However, the overall rate of the mechanism is often controlled by a few reactions, subsets of the full mechanism.
- Key: Identify the “Intrinsic Low-Dimensional Manifold” (ILDM).
- May not be true species and individual reactions, but composites.

- May be different ILDM in different regions -- use adaptive chemistry.
- Rate still depends on temperature and chemical concentrations only.
- Collect each calculation and simply look up rate if T and concentration conditions recur, rather than repeating detailed calculation:
- In Situ Adaptive Tabulation (ISAT)
- Use these strategies with turbulent LES/FDF model through parallel computing; here, simple H2/O2.

**Notes:**
Dimension Reduction Methods: Quasi-steady state assumptions (QSSA); 
Intrinsic low-dimensional manifolds (ILDM) ; Trajectory generated low-dimensional manifolds (TGLDM) ; Rate-controlled constrained equilibrium (RCCE)  ; Flamelet generated manifolds (FGM)  ; Roussel & Fraser algorithm (RF) ; Pre-Image Curves

Reaction trajectories for hydrogen autoignition from many initial states showing their attraction to manifolds of successively lower dimensions.  Eventually all trajectories tend to chemical equilibrium – the 0D manifold (blue dot).

## However, “cyberinfrastructure” is a fairly recent, useful organizing concept.

- It recognizes the coupling of infrastructure:
- Computer data acquisition, processing, and storage;
- Simulation, now accepted as one of the routine practical tools of conducting science and engineering;
- Dramatic increases in computing power, including terascale speed, storage, local cluster computing, and Internet-enabled grid computing;
- Ubiquity of the Web, linking people to each other and to information.
- Not long ago, none of these advances were established.
- Now, they set the stage for new approaches to combustion research and development.

## In this light, combustion research is a pioneer not only in computing but in use of cyberinfrastructure. 

- Combustion has been a natural.
- Diverse physical and chemical systems.
- Large volumes of data: acquisition, archiving, quantified uncertainties, validation, visualization.
- Modeling from atoms to autos to the atmosphere.
- Cyberinfrastructure is aiding the combined use of computing, networks, and inter-researcher collaboration.

## CI value cuts across agency missions, too.

- Breadth of molecular modeling codes and applications was seeded by sponsored research.
- Supercomputer centers for high-performance computing by NSF, DoD, DOE, NASA.
- Collaboration tools beyond teleconferencing beginning to be used.
- Companies, including DoD contractors, are using data and findings from combustion research.

## How do we best use it?

- More powerful computing:
- Grid computing
- “Simulation-Based Engineering and Science”
- “Cyber-Enabled Discovery and Innovation”
- Different ways of collecting data.
- Remote sensor networks.
- Remote experiments.
- More effective collaboration and information transfer:
- “Virtual organizations” (gateways, collaboratories).

## Virtual Organizations (VOs) can couple all three.

- We’ll hear from TNF and PrIMe as two examples.
- Not just websites...

## Slide 12

## Useful, but compare to capabilities of nanoHub.org :

## Slide 14

## Slide 15

## Slide 16

## Slide 17

## Slide 18

## Big or small, both can be useful.

- nanoHub.org has wide usage.
- In contrast, a virtual organization may be a small group of geographically dispersed collaborators:
- Data storage, retrieval, visualization
- Models and model results
- Data vs model comparisons
- Conferencing (NetMeeting, etc.)
- Another possibility: An interactive data resource like webbook.nist.gov/chemistry

## One activity setting the stage for CI action in combustion was an April 2006 workshop. 

- “Cyber-Based Combustion Science,” Apr 19-20, 2006
- Report authors: Trouvé, Haworth, J.H. Miller, Su, & Violi
- See http://www.nsf-combustion.umd.edu/
- Three key themes:
- High-performance computing and sensor-driven modeling
- Chemical data/software libraries and collaboratories
- Education

## April 2006 NSF Workshop recommendations:

- Quantitative, predictive capabilities for engineering-level simulations of combustion systems will require a cyberinfrastructure-enabled framework built around _high-performance computing_ and _collaborative science_ infrastructures:
- Ongoing developments in numerical combustion, driven in part by continued access of combustion scientists to high-end HPC centers.
- Emergence of chemical digital libraries as data/software stores and collaboratories.
- Coordination of efforts in and across other sub-communities of scientists and engineers in a common framework.
- Use opportunities to improve combustion education:
- Renewed emphasis on pedagogical ties between fundamentals and applications;
- Promotion of combustion as a multi-scale discipline;
- Integration of data science and scientific computing into the curriculum.

## That then is our charge.

- We want to propose concrete steps forward to aid such approaches.
- Listen and comment on different aspects.
- Tomorrow, develop specific plans to propose.

## Workshop agenda

- Wednesday, March 28, 2007, 1:30-5:30pm
- 1:30pm: Review of Workshop context, agenda, and goals
- 2:00 pm: Perspectives from the TNF Workshop, Rob Barlow, CRF
- 2:40pm: PrIMe – A Virtual Organization; Phil Smith (Utah), Michael Frenklach (Berkeley), Greg Smith (SRI)
- 3:20pm: BREAK
- 3:40pm: Developing Cyberinfrastructure for Data-Oriented Science and Engineering; Fran Berman, Director, SDSC
- 4:20pm: Insights from the Pittsburgh Combustion Simulation Workshop;  Geo Richards, NETL
- 5:00-5:30pm: Open Discussion
- Thursday, March 29, 2007
- 8:00am: Panel-Oriented Discussion of Opportunities and Action Items
- 9:30am: Breakout sessions to identify needs
- 10:30-11:30am: Recap of breakout sessions; Identification of Action Items