2.12  Temperature dependent materials

QuickWave allows also for analysing temperature dependent materials. This is a capability available in advanced QW-BHM module. There are six thermal parameters that can be determined: Initial temperature, Specific heat (in [J/(g°C)]), Density (in [g/cm³]), and Thermal conductivity (in [W/(cm°C)])in each of three directions. Specific heat and Initial temperature are relevant only if the QW-3D package operates with the optional QW-BHM module. The Density is used in QW-BHM, and also for calculating Specific Absorption Rate (SAR). The Thermal conductivity is taken into account when additionally QW-HFM module for heat flow analysis is used.

The only media that can be declared and will be considered as temperature dependent are dielectric isotropic or dielectric anisotropic type. Metals (PEC or Metallic) are not heated during the simulations - power generated in lossy metals is added to the neighbouring dielectric region. Dispersive media (Dielectric Dispersive, Dielectric Dispersive Anisotropic, Dielectric Dispersive Nonlinear, Metamaterial, Ferrite) can be included in the scenario, but the power dissipated therein is calculated with an approximate formula, using constant conductivity. For Drude and Lorentz dispersion, this effective conductivity is equal to Sigma and SigmaM settings; for Debye it is modified partially accounting for series losses. Thus dissipated power, enthalpy and temperature patterns in dispersive media are only approximate. Moreover, these media parameters cannot be changed as a function of temperature.