Microwave Ovenexamples|products|Murata Software Co., Ltd.

Example1 Microwave Oven

General

  • The heating of a piece of meat on the bone placed in a microwave oven is simulated.
     

  • It is solved by cascading the electromagnetic waves analysis and the thermal analysis.
     

  • Unless specified in the list below, the default conditions will be applied.
     

 

Analysis Space

Item

Settings

Analysis Space

3D

Model unit

mm

 

Analysis Conditions

Item

Settings

Solver

Electromagnetic Analysis [Hertz]

Thermal Analysis [Watt]

Analysis Type

Electromagnetic waves analysis: Harmonics analysis

Thermal analysis: Steady-state analysis

Options

Select “Ignore the influence of face/edge electrode thickness” *

* This is the default setting. There are no face electrodes with this model. Therefore it is irrelevant to select it or not.

xx

 

Mesh tab, Harmonic analysis tab and Open boundary tab are set as follows.

Tabs

Setting Item

Settings

Mesh

Mesh Size

20

Element type

2nd-order element

Adaptive mesh

Off (to shorten the calculation time)

Frequency-Dependent Meshing

Reference frequency: 2.45×10^9[Hz]

Harmonic analysis

Frequency

Minimum: 2.45×10^9[Hz]

Maximum: 2.45×10^9[Hz]

Input

10[W] *

 

* The power of actual microwave ovens is much higher than this.

The temperature distribution at steady state is analyzed in this exercise. Therefore, if the actual power is applied, the resulting temperature will be too high.

The input power is low to prevent it.

 

Model

A waveguide is placed on the top of a cavity box. An I/O port is set at the end of the waveguide.

The meat on the bone is placed on a plate. The temperature of the bottom face of CAVITY is 20[deg].

 

 

Body Attributes and Materials

Body Number/Type

Body Attribute Name

Material Name

Mesh Size

0/Solid

CAVITY

000_Air(*)

 

5/Solid

WAVEGUIDE

000_Air(*)

 

6/Sheet

Imprinting body

 

 

13/Solid

PLATE

PLATE

8

75/Solid

BONE

BONE

8

96/Solid

MEAT

WATER

 

* Available from the Material DB

 

 

 

Material Name

Tab

Properties

PLATE

Permittivity

Relative Permittivity: 7.0

tanD: 0.0

Thermal Conductivity

1.5[W/m/deg]

BONE

Permittivity

Relative permittivity: 7.0

tanD: 0.1

Thermal Conductivity

1.5[W/m/deg]

WATER

Permittivity

Relative Permittivity: 76.7

tanD: 0.16

Thermal Conductivity

1.5[W/m/deg]

Boundary Conditions

Boundary Condition Name/Topology

Tab

Boundary Condition Type

Settings

PORT1/Face

Electric

I/O Port

Reference Impedance:
Select “Use the characteristic impedance calculated from the port structure”.

EW/Face

Electric

Electric wall

 

20deg/Face

Electric

Electric wall

 

Thermal

Temperature

20[deg]

Outer Boundary Condition

Electric

Electric wall

 

The default settings are “Magnetic wall” and “Adiabatic” for the electric and thermal boundary conditions respectively.

 

Results

The model is well heated overall.