Visualizing Multivalued Data from 2D Incompressible Flows Using Concepts from Painting R. M. Kirby H. Marmanis D. H. Laidlaw Brown University Presented

Visualizing Multivalued Data from 2D IVisualizing Multivalued Data from 2D Incompressible Flows Using Concepts ncompressible Flows Using Concepts

from Paintingfrom Painting

R. M. Kirby H. Marmanis D. H. Laidlaw R. M. Kirby H. Marmanis D. H. Laidlaw Brown UniversityBrown University

Presented by Hsin-Ji Wang & Chaoli Wang

Oil Painting of the Impressionist Basic Fluid Mechanics Concepts Related Work Visualization Methodology Example 1: Rate of Strain Tensor Example 2: Turbulent Charge and Turbulent

Current Summary and Conclusions

Oil Painting of the ImpressionistOil Painting of the Impressionist

The multiple layers of brush stokes in these paintings provide a natural metaphor of constructing visualization from layers of synthetic “brush stokes”.

The works of three painters they studied– Gogh, Vincent van (1853-1890)– Monet, Claude-Oscar (1840-1926)– Cezanne, Paul (1839-1906)


Two Cypresse (1889)

Van Gogh, whose large, expressive, discrete strokes carry meaning both individually and collectively.


Woman Seated under the Willows

Monet, whose smaller stokes are often meaningless in isolation – the relationships among the stokes give them meaning, far more than in van Gogh.


The Card Players (1890-1892)

Cezanne, who combined strokes into cubist facets, playing with 3D perspective and time within his paintings more than either van Gogh or Monet. His layering also incorporates more atmospheric effects. In a sense, his work shifts from surface rendering toward volume rendering.


Van Gogh's The Mulberry Tree (1889) illustrates the visual shorthand that van Gogh used with his expressive stokes. Multiple layers of stokes combine to define regions of different ground cover, aspects of the hillside, and features of the tree. An underpainting shows the "anatomy" of composition of the scene in broad stokes.


Capture the marriage between direct representation of independent data and the overall intuitive feeling of the data as a whole

Space: encode different information at different scales

Time: design visualizations so that important data features are mapped to quickly seen visual features

Choose the artists in whom you have a passionate interest, any artist has lessons to offer to visualization

Basic Fluid Mechanics ConceptsBasic Fluid Mechanics Concepts

Vorticity Reynolds Number Rate of Strain Tensor Turbulent Charge Turbulent Current


Vorticity – ξ = × u▽ – Vorticity is primarily used to describe the rotation of fl

uid.– If × u▽ = 0 then the fluid is irrotational– else the fluid is rotational


Reynolds Number– Reynolds number = ρVD / μ – Reynolds number is proportional to { (inertial force) /

(viscous force) } and is used in momentum, heat, and mass transfer to account for dynamic similarity.


Rate of Strain Tensor

– The symmetric part is known as the rate of strain tensor

– The anti-symmetric part is known as vorticity


Turbulent charge and turbulent current

– The turbulent charge and turbulent current, collectively referred to as turbulent sources, could substitute the role of vorticity in more complicated flows.

Related WorkRelated Work

Multivalued data visualization– “Feature-based” methods– Statistical methods– Icons– Layering

Flow visualization– Spot noise– Line integral convolution

Computer graphics painting

Visualization MethodologyVisualization Methodology

Developing a visualization method involves– Breaking the data into components– Exploring the relationships among components– Visually expressing both the components and

their relationships

Example 1: Rate of Strain TensorExample 1: Rate of Strain Tensor

Data breakdown Visualization design

– Priority Velocity Vorticity

– Layering Primer Underpainting Ellipse layer Arrow layer Mask layer


Simulated 2D flow past a cylinder at Simulated 2D flow past a cylinder at Reynolds number = 100Reynolds number = 100


Simulated 2D flow past a cylinder at Simulated 2D flow past a cylinder at Reynolds number = 500Reynolds number = 500


Experimental 2D flow past an airfoilExperimental 2D flow past an airfoil

Example 2: Turbulent Charge and Turbulent currentExample 2: Turbulent Charge and Turbulent current

Drag reduction (riblets) Data breakdown Visualization design

– Priority Overall location of the turbulent charge Vorticity Structure of the flow – velocity field Fine details

– Layering Primer and underpainting Arrow layer

Turbulent source layer Mask layer

Turbulent charge and turbulent current of Turbulent charge and turbulent current of simulated 2D flow past a cylinder at Reynolds simulated 2D flow past a cylinder at Reynolds

number = 500number = 500


Reynolds Reynolds number = 100number = 100


Reynolds Reynolds number = 500number = 500


Combination of Combination of velocity, vorticity,velocity, vorticity, rate of strain, tu rate of strain, turbulent charge arbulent charge and turbulent currnd turbulent current for Reynolds ent for Reynolds number = 100number = 100


Summary and ConclusionsSummary and Conclusions

Borrow concepts from oil painting– Underpainting– Brush strokes– Layering

Represent many values at each spatial location in different perspectives

Get a complete idea of both the dynamics and kinematics of the flow

Provide catalyst for future understanding of more complex fluid phenomena

Thank you!Thank you!

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Visualizing Multivalued Data from 2D Incompressible Flows Using Concepts from Painting R. M. Kirby H. Marmanis D. H. Laidlaw Brown University Presented