Air box Dimensions

pmcardle
pmcardle Altair Community Member
edited October 2020 in Community Q&A

  It is my understanding that when using an FEM simulation decoupled from the MoM,  the surrounding airbox should be at a minimum of wavelength/4. Is this the wavelength of the incident light? or is this the effective wavelength of any dielectric media that this airbox is surrounding?

 

 

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Answers

  • Mel
    Mel Altair Community Member
    edited October 2020

    The size should be 1/3 of the free space wavelength at the simulation frequency. The air box forms the absorbing boundary condition for the FEM only solution.


    An exception is waveguides that are fully enclosed, e.g. a waveguide filter with FEM modal ports. Here the boundary consists of the PEC walls of the waveguide and you do not need to add an airbox.