HIERARCHICAL TREES OF UNSTEADY SIMULATION

DATASETS

HIERARCHICAL TREES OF UNSTEADY SIMULATION

DATASETSMarek Gayer and Pavel Slavík

Computer Graphics GroupDepartment of Computer Science and EngineeringFaculty of Electrical Engineering of CTU in Prague

Czech Republic

The IASTED International Conference on APPLIED SIMULATION AND MODELLING ~ASM 2004~ June, 28 - 30, 2004 Rhodos, Greece

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2ASM 2004

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Outline of the presentationOutline of the presentation

Introduction to real-time simulation and visualization of various physical phenomena's

Using storage for real-time data replaying Unsteady simulation datasets Our solution overview

– Stored data - Fluid simulator, Particle system– Forming UDS to Tree Structures– Features, advantages and comparison

Demonstration of results Conclusion and future work

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www.cgg.cvut.czReal-time simulation and visualization of various physical phenomena's

Real-time simulation and visualization of various physical phenomena's

For simulation and visualization of various nature phenomena:– Water and liquids– Clouds, smoke– Fire and combustion– Special effects

ACM SIGGRAPH Proceedings(see references in our paper)

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Real-time simulation advantagesReal-time simulation advantages

Possibility to quickly obtain the results Possibility to get a good overview of the

dynamics of the simulated process Easy manipulation of the simulated model Interactive changes to the simulated

process with immediate visualization response

Visualization of the results in readable and easily understandable form

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Storing results for real-time replayingStoring results for real-time replaying

Used when computation is too slow for real-time simulation and visualization

Results are stored on hard disk, then real-time replayed– Data sets for selected

characteristics– AVI and MPEG files– Limited interaction

Our concept:HIERARCHICAL TREES OF UNSTEADY SIMULATION DATASETS

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Unsteady simulation datasets (UDS)Unsteady simulation datasets (UDS)

Stores one or more characteristics for selected time part

Can allow real-time replaying of results Full interactivity in visualization part After storing, no interactivity in

simulation part No additional changes to already

computed data and configuration

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Example storage of data - fluid simulatorExample storage of data - fluid simulator

Dividing boiler area to structured grid cell arrays containing:– Velocities– Masses/Pressures

– O2 concentrations

– Temperatures State update Principle of local

simulation

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Example storage of data - particle systemExample storage of data - particle system

Used for both simulation and visualization of the combustion process

Virtual particle system approach

Simplified combustion and heat transfer computation

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Forming UDS to tree cluster structureForming UDS to tree cluster structure

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www.cgg.cvut.czChanging simulation parameters in each of the tree node

Changing simulation parameters in each of the tree node

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UDS tree features and advantagesUDS tree features and advantages

Incremental and step by step solution Re-playable results of the simulation Interactive addition and deleting of parts Hierarchical storage of various states Interactive change of boundary

conditions in each of the nodes Constructing various paths in the tree Extending of already computed tasks

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Comparison against direct simulationComparison against direct simulation

Can run in orders fasterSeeking and skip frame ability

Creating hierarchy of replay-able resultsIncremental step-by-step solutionInteractivity is allowed only in the nodes

of the treeRequires disk bandwidth and capacity

Note: Please refer to our paper for more detailed comparison and samples with performance measurements and discussions

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Our interactive combustion systemOur interactive combustion system

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Possible applicationsPossible applications

Originally used for our fluid application for combustion processes

Can be reused for others simulation and visualization applications, that either use or can be extended to use unsteady datasets

E.g.: simulation and animation of liquids, water and gaseous phenomena

17ASM 2004

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Conclusion and future researchConclusion and future research

Concept of Unsteady Datasets Tree offers:– Overcomes drawback of unsteady datasets, of

loosing interactivity on the simulation side. – Incremental, step-by-step construction and

replaying of simulation configurations with interactive visualization of results

– Can be used in general simulation and modelling applications based on unsteady datasets

Future research: – Optimal data compression and encoding methods– Testing with very large data sets– Various data Interpolation techniques

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Thank you for your attention.Thank you for your attention.

???Do you have any questions ?