Material Microwave Absorption in CST 

Welcome

Hi, my pleasure. For E-field, u may refer to this video how the E-field and surface current flow ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-5KaB0XIZCjU.html Hope it helps. :)

@@LYSStuff thank you very much!

Hi, Thanks. For references, you may refer to 1. www.frontiersin.org/articles/10.3389/fmats.2021.633079/full 2. www.jpier.org/PIER/pier140/44.13042407.pdf 3. link.springer.com/article/10.1007%2Fs00339-018-1564-y 4. www.researchgate.net/publication/341910876_Microwave_absorption_study_of_dried_banana_leaves-based_single-layer_microwave_absorber Hope it helps. :)

Hi, my pleasure. You are free to use my video as long as you give credit. :)

@@LYSStuff Thank you very much, your CST absorbing material video is of great help to me, and I would like to extend my high regards to you

Hi, please refer to this Video "ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-UKfOVduw1JM.html". Hope it helps. :)

Hi, I'm using Microwave & RF Template--> Antenna. The simulated results are convincing.

@@LYSStuff thank you very much

Hi Fath, you may define any New material in CST. For your reference, you may refer the link below: 1. How to Define New Material in CST ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-Fa23oNEeiyg.html 2. How to Add New Material in CST Library ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-4yYHl3IkaDo.html Hope it helps. :)

Hi, yes. You are right, the absorption will change with respect to temperature. But in CST simulation, only able to set the temperature on the material. Because the temperature actually effects on permittivity, permeability and conductivity parameters of the material classes. Once the temperature changed for a material, it will change the values of material permittivity, permeability and conductivity properties over the frequency range. Example, the changed value of material permittivity will effect on the microwave absorption. The temperature dependency curve can be defined in the Temperature Dependent Materials. After definition the material table can be visualized as a 1D plot by selection in the Navigation Tree.

I not sure about the plot absorption VS temperature graph in CST. Because it will be specific at single frequency. I think we only able to set the thermal of the material value with variable. The parameter sweep the variable of material thermal value. And the graph still S11 vs Frequency with various of thermal sweeping value. Hope it helps. :)

Hi, in CST --> 2D Results--> Port Modes --> ()for Example Port 2 --> click on e1 or h1, and then read mode type. Depend on your design and waveguide port (port mode) setting in CST. If you need more information, may refer to CST help file. For my case, is TEM mode. You can try to simulate rectangular waveguide and check on TE mode, default is TE01 as usual.

Hi, in my video, only using Port 1 and port 2.

Hi, thanks. The workflow is use is Waveguide. unit in cm and frequency in GHz. Hope it helps. :)

Thank you, but we should choose lossy material for the simulation because Lossy medium:- It is the medium, where the EM wave loses its power. And it aalso defined the conductivity value for the aluminium. Lossless medium:- It is the medium, where the EM wave does not lose power. Most of the material is not ideal material as perfect conductor.

Hi, this is to create a TEM waveguide and the plane containing the "WaveGuide port". Due to my design is symmetry, I can set (Et=0 in X axis and Ht = 0 in Y axis) or (Ht=0 in X axis and Et = 0 in Y axis), It will get same result. You also can set the boundaries condition to symmetry plane. CST Microwave Studio has a symmetry setting located in at Simulation->Boundaries->Symmetry Planes. You may refer to this Note: throberts.blogspot.com/2016/08/notes-on-symmetry-using-cst-microwave.html Hope it helps. :)

@@LYSStuff can you show me how to set boundary condition if my design is not symmetry?

Hi, you can set this (Ht=0 in X axis, Et = 0 in Y axis,Open in Z axis, then set distance at "background option" ). The setting is same at my video just change the Ht=0 in X axis, Et = 0 in Y axis.

@@LYSStuff can I use open (add space) in all coordinates instead?

Yes you can, if your simulation is an antenna design with waveguide port (sma). If you plan to simulate like this enclosure direct to the same, then the boundary condition should be as previous mentioned setting.

Good idea. Meanwhile, You may refer to this paper 1st. www.researchgate.net/publication/322507892_EMI_shielding_based_on_MWCNTspolyester_composites

Hi, at 05:33, you may found the setting for the distance. With the boundary condition setting, the distance of port doesn't affect much on the absorption. Because the wave is guided.

@@LYSStuff thank you. please could you help me to measure the electric permivivity by CST program

@@mohammedkhamess8882 Hi, We can measure permittivity using CST. We only can extract permitivity and permeability of Metamatarial using CST you may refer to video below 1. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-ULCkZFxRW44.html 2. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-8xYLyV048hk.html If you wanna to define permittivity material by ourselves. you may refer to this. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-Fa23oNEeiyg.html Hope it helps. :)

Hi, yes. Is the same setup. Just Shielding effectiveness mainly focus S21 with SE material and without SE material.

@@LYSStuff OK ! But how S21 can be bigger with wood sheet than an aluminium sheet ;-(

@@LYSStuff Is that possible to get your email adresse to talk ?

For sure aluminium sheet, S21 has lower power receive compare to wood sheet.

@@LYSStuff do you have a formula to convert S21 and S11 to SE

Hi, I only have these related to shielding application ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-GxL46brvp2Q.html ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-wLo3HcW9x1g.html I didnt found any useful CST EMI shielding video or course in youtube. But you may refer to ETS lindgren, R&S or Keysight for EMI shielding application

Hi, is Transient solver. You may refer to 02:41, the "setup solver" is "T". Hope it helps. :)

@@LYSStuff if i need to design microwave lens/ unit cell , can you suggest me project template or any related video?

Len design usually is single Len. Therefore no need to use unit cell. Antenna template is fine.

Hi, this is rare. Maybe can check on the material part. Used same material as well?

@@LYSStuff I seem to have same CST version - yes wood, same distance, same symmetry, freq, mesh etc

@@LYSStuff I have 2022 version CT as well, wood params look the same as yours..

Hmm... If everything is the same, I also no idea why different results. Sorry.

Here is the calculation of reflection loss, you may refer to this video ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-GxL46brvp2Q.html

@@LYSStuff thank you for help but ıt doesn't help me because complex numbers are given error somewhere so I can't fix it. Thank you for attention.

@@cemalaka5812i see, RL(magnitude) =sqrt((real) ^2+(imag)^2)

@@LYSStuff actually main problem in Zin calculation

@@cemalaka5812 for Zin, you may refer to this video ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-rg9Shd2RoL4.html