**Screenshots of penacho - Smokestack pollutant dispersion simulator**

User interface: parameters input at chimney output. Program starts with values of a typical problem. Every label has its SI unit and a tooltip explaining its meaning. Label names are equal to that used in source code. | |

UI: reference values. | |

UI: atmospheric stability matrix. You choose 6 representative air velocities, and the atmospheric stability categories according to Pasquill (see pop-up). | |

UI: wind rose for each season, and its associated probability matrix. Pop-up window comes by clicking the "What's this?" button on the wind roses graph area. | |

UI: plumes solving. Plume evolution is modeled by a system of differential equations (ODE). Sundials (Cvode) library solves them really fast (around 2--4 seconds a typical problem). As penacho is oriented to research and education, you can choose some of the numerical solver parameters and data storage options. Memory allocation is dynamic, so you can solve from 50 m to 50 km (or more). | |

UI: concentrations calculation. This step computes concentration on a user selectable 3 dimensional mesh. It's a high-nested calculation that request lots of memory and CPU. | |

3D mesh example: concentration is computed exactly at intersection points. Vtk library interpolates values in the rest of space. | |

UI: Plume representation and save. All plume solved (48 according to the different conditions) can be drawn. Data can be saved as a text file (labelling each variable), or CSV (comma-separated values) exportable to spreadsheet. | |

What's this? over variable to plot. Every variable on the modeling can be drawn. | |

Plume 3D graph. Color bar shows the fluid mass fraction value (adimensional). This program window is completely interactive: you can move, rotate o zoom the image. Ground plane shows the need of reflection of vertical dispersion. | |

Plume 3D graph for a stable atmosphere: plume rise has a narrow envelope. | |

Vtk visualization library let you see graphics with red-cyan 3D glasses. | |

CSV result file opened by OpenOffice Calc. It's a five click job to graph plume height (z vs x) or a detail of temperature (T vs x) drop at the first 50 metres. | |

UI: concentration and sedimentation representation and save. | |

Carbon monoxide concentration distribution on the ground. It looks like a 2D graph, but it is a 3D bird's-eye view completely interactive: you can move, rotate or zoom the image. | |

3D views of CO concentration for a 2500 m x 2500 m x 200 m volume. In addition to ground distribution there are iso-concentration surfaces for three different values. (An isosurface represents points of a constant concentration value.) | |

CO ground distribution and a vertical grid plane. User can choose to color on red the local volume maximum, or a fixed value (normally the maximum on ground). Bigger values will be colored in red too: this way you can get some information from a wide data range volume. | |

Ground CO distribution and an iso-concentration surface for a yearly study. Wind rose leads the main 8 plume directions. The average values are calculated according to the probability matrix, which depends on winds ranges and wind directions for each season. Wind blow more often from the north in this study land. You can see that the nearby surrounding of a plume has very little contamination. | |

Three simulations for different smokestack heights. Penacho helps you to see that the taller the chimney is, the fewer contamination on ground. Great conclusion. | |

Parametric analysis for atmospheric stability: from A (very unstable, upper left corner) to F (stable, lower right corner). It's the most important parameter for pollutant distribution. More atmospheric unstability causes more contamination on ground, on a smaller area, and closer to the emission point. Red color means equal or bigger values than the local maximum at F case. | |

Parametric analysis for different wind magnitudes: more wind speed causes more contamination on ground, on a smaller area, and closer to the emission point. | |

Concentration data can be saved as CSV or as VTK structured points. MayaVi (and some other applications) can open .vtk files, graph multiple isosurfaces and grid planes, make animations, etc. | |

MayaVi plotting another penacho VTK exported file. |