Basic Heating Module
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Modelling of heating of rotating loads
In a typical domestic microwave oven a more uniform temperature distribution within the load is obtained through rotating of the load during heating. Such slow movement of the heated object may to a great extent affect the temperature field. In order to maintain high computational accuracy also in such scenarios, the QW-BHM module has a built-in mechanism accounting for this effect.
The load rotation mechanism lets the user simulate heating of arbitrarily shaped objects rotating around any point chosen on the XY plane. Thanks to this feature it takes just a few mouse clicks to prepare all the data necessary to perform simulation of such problems for specified heating time during which the object is being rotated with a given angular speed.
Multiple rotation and movement along arbitrary trajectories for heated objects
QW-BHM (Basic Heating Module) for QuickWave-3D provides a novel regime of operating the FDTD solver: the possibility of simulating microwave heating problems.

The software has been prepared to work in sophisticated regimes, modelling rotation and movement of the heated load(s) even along complicated trajectories, etc. Transfer of the heat generated by electromagnetic fields can be modelled with external or internal Heat Transfer Module or by coupling QuickWave-3D simulations to external computational fluid dynamics packages.
QW-BHM automatically modifies media parameters in thousands of FDTD cells filled with different media
and heated up differently - all accomplished in a matter of seconds!

Each "thermal" iteration requires many FDTD iterations to reach the new electromagnetic steady state
starting from the previous steady state - but less than would be needed to reach the new steady state
starting from the initial zero field distribution.

Special BHM functionalities:
modification of material parameters as a function of dissipated energy
modelling of the load rotation and movement along an arbitrary trajectory
modelling of rotation and movement of multiple objects rotating around different rotation axis and with different speeds or along different trajectories
modelling of the rotation of metal objects
automatic tuning of the source to the deepest resonance in the considered frequency band (this option mimics the physical behaviour of the real microwave power sources like magnetrons)
manual tuning of the source (user indicates the new frequency)
Rieke display for SWR
automatic source parameters changing (frequency, amplitude and delay) in the consecutive heating steps, according to user specification, performed for each source separately
analysis of the heat transfer problems taking into account divided cells (internal Heat Flow Module using non-linear model)
possibility of coupling Basic Heating Module with external applications modelling effects not supported in QW-BHM
modelling of the load rotation and movement along an arbitrary trajectory
modelling of rotation and movement of multiple objects rotating around different rotation axis with different speeds
or along different trajectories
Frequency tuning
The approach of applying a monochromatic source is the most popular one in microwave power modelling and has been followed so far. However, it does not reflect all phenomena that occur in real life applications. The most widespread microwave power source, a magnetron, is an imperfect device gradually changing its frequency during the heating, and in fact, it may even "jump" from one frequency to another. Let us quote here the two effects of frequency "pulling" by the load and "pushing" by the power supply. Although both have been deeply investigated, the question about the actual operating frequency (or frequency spectrum) of the magnetron as a function time, and for a particular load, is still puzzling for many designers, especially those dealing with small low-loss loads.

Automatic frequency tuning assumes that the source tunes automatically to the deepest resonance in the considered frequency band, while manual frequency tuning assumes that user indicates the new frequency value.
The Heat Flow Module (QW-HFM) ia a tool that supplements the QW-BHM in modelling of the heat transfer effect. Thanks to this, users who work with microwave heating applications can ensure greater accuracy of the simulations done with the QuickWave package.

The external QW-HFM is a stand-alone 32-bit application that communicates with the QW-BHM module and the QuickWave package through text files generated automatically during simulation. The files contain data on the current enthalpy field, dissipated power field and the temperature. The QW-HFM applies the heat transfer equation to these data in order to obtain the diffused enthalpy field (the diffusion time depends on the QW-BHM time step specified by the user) and returns the results back to the QW-BHM module.
Heat Flow Module
The implementation of internal QW-HFM module takes into account the divided cells (without boundary conditions) and assures faster (also in multiprocessor/multicore version) heat flow simulations. The internal QW-HFM module uses nonlinear model (it uses a phase-change model in the heat transfer analysis) and is also available in 64-bit version.
Load rotation is the most popular temperature-equalising mechanism in domestic microwave oven. However, different types of load movements are also used in the engineering practice or experimented with in research. For example, linear translation is widespread in industrial tunnel installations. Moreover, a real-life scenario may contain several bodies moving differently, e.g., a turntable and a mode stirrer may rotate with different speeds and around different axes.

QW-BHM has been extended to include both rotation and translation mechanisms, of many items independently:
translation is facilitated along an arbitrary piece-wise linear trajectory in xy, xz and yz plane
rotation is facilitated around an axis parallel to the z-axis
discover accurate EM modelling