Monday, November 22, 2010

Parameters of the CHC plug-in

In Tonatiuh release 1.1.2, the latest one as of the writting of this post, we have introduced a new shape plugin, the 2D Compound Hyperbolic Concentrator plug-in, which in Tonatiuh is called "Trough_CHC".

The mathematical model defining the CHC implemented in the Trough_CHC plug-in is taken from the following article:

William L. Eichhorn, "Generalized conic concentrators", Appl. Opt. 21, 3887-3890 (1982).

The plug-in, when added in Tonatiuh as a child to a TShapeKit node, implements one side of a 2D Compound Hyperbolic Concentrator.

From Tonatiuh Blog Figures

As indicated in the above figure, the geometry is defined by the following 5 parameters:
  • r1, the distance in the x-direction from the origin of the CHC implicit local coordinate system to the middle of the lower border, oriented in the z-direction and centered around the x-axis. In the negative x-direction, r1 is also de distance in x-axis where the focus of the branch of the hyperbola represented by the plug-in is located (point F in the figure).
  • p1,  the distance in the x-direction from the origin of the CHC implicit local coordinate system to the middle of the the upper border, oriented in the z-direction and centered around the x-axis.
  • lengthX1, the length of the lower border, oriented in the z-direction and centered around the x-axis.
  • lengthX2, the length of the upper border,oriented in the z-direction and centered around the x-axis.
  • height, the distance in the y-direction between the lower and the upper border.
By defining lengthX1 and lengthX2 appropiately, it is possible to combine several trough CHC plug-ins to represent a large variety of hyperbolic concentrators. As an example, the figure below shows an Hexagonal CHC constructed using six troguh CHC plug-ins.

From Tonatiuh Blog Figures

    Friday, November 19, 2010

    Tonatiuh’s website number of visits and bounce rate are growing fast

    Tonatiuh’s website started on June 28, 2008. Thus, we are currently in the day 143 of the third year since the opening of the website. With only 39% of the third year of the website passed by, today the number of visits to the Tonatiuh website has exceeded the total number of visits to the website during the previous year. The fact that the number of visits to the Tonatiuh’s website is increasing at an exponential rate is an indication that Tonatiuh is increasingly kwon and used all over the world.

    From Tonatiuh Blog Figures

    Another indication of the consolidation of Tonatiuh as a reference program for the analysis of the optical and energy behavior of solar concentrating systems is the continuous increase in Tonatiuh's website “Bounce Rate”. According to the information shown in Figure 1, more than 63% of Tonatiuh website’s visitors are recurrent visitors.

    Thursday, November 18, 2010

    Release of version 1.1.2 of Tonatiuh

    We just released version 1.1.2 of Tonatiuh. This is a minor release version of the program. Its main characteristics are the following:
    • It incorporates an Update Manager, which allows the users to check if there is available a newer version of the program than the one she or he is using, and to download it in case it is available.
    • It adds a new shape plug-in to the list of Tonatiuh standard shape plug-ins. This new shape plug-in named "ShapeTroughCHC" allows the user to create trough-like Compound Hyperbolic Concentrators.
    • It fixes the error associated with the lack of immediate response of a Tracker to user-induced changes in the transformation of its parent TShapeKit separator or in any of its ancestors.
    • It fixed the error associated with the brief appearance of a ghost window when opening the Sun Position Calculator.
    Figure 1 shows a view of a parabolic trough working in tandem with a Compound Hyperbolic Concentrator acting as a secondary concentrator.
    From Tonatiuh Blog Figures

    Tuesday, November 9, 2010

    We are starting a tutorial series to illustrate the use of Tonatiuh

    To illustrate the use of Tonantiuh we are starting today a tutorial series, which will be posted in the wiki of the main Tonatiuh website (

    The tutorial that starts the series will explain how to use Tonatiuh to model and analyze a tower system with 500 one-facet small heliostats.

    From Tonatiuh Wiki Figures

    This tutorial will explain how to insert "tracker" plug-ins in the modeling of the heliostat field to ensure that when the user changes the sun position the heliostats are  automatically reoriented so that they keep directing their reflected sunlight towards the receiver located on top of the tower.

    In addition, the tutorial will also explain how to use the scripting capabilities of Tonatiuh to automate the generation of an optical efficiency matrix for the solar heliostat field.

    To access the index of the tutorial series, please, follow this link.

    Please, give us feedback, so that we can continue improving Tonatiuh, and providing you the tools and information you need to use it.

    Best regards,

    Monday, November 1, 2010

    Improved instructions to install Tonatiuh's IDE under Windows

    One of the many good things of Tonatiuh is that it is build upon one of the best set of open source libraries available (Qt, Simage, Coin3D, SoQt, Marble, Berkeley DB). This allows the program to benefit from the continuous improvement and increase in functionality of those libraries and their related tools.

    Under Windows, the recent improvements on the installation and set up tools of the MinGW/MSYS compilation and linking environment and of the Qt, Coin3D and Marble libraries has resulted in a drastic simplification and a dramatic reduction in the time needed to install and configure the Tonatiuh's development environment.

    Now, if you follow the updated instructions posted on the Wiki of the Tonatiuh website regarding how to install and configure the development environment of Tonatiuh under Windows XP, Windows Vista, and Windows 7, you will need just two to three ours to:
    • Install the complete development environment,
    • Download Tonatiuh's source code from its Googlecode SVN server,
    • Build the latest stable version of the program from its source code, and
    • Be ready to contribute to the improvement of the program, should you decide to do so. 
    These are good news to any one interested in being able to build the latest version of Tonatiuh without having to wait until the next official program release, or to any one interested in collaborating in the development of the program.

    To access the updated wiki instructions regarding how to install and configure Tonatiuh's development environment, please, go to this link.