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Posted:
6 months ago
30 dic 2024, 00:22 CET
Your message is clear and professional! Here's a slightly refined version to enhance readability and flow:
Hello,
The default directions of piezoelectric material properties in the built-in COMSOL material library (in 3D space) are as follows:
1 → x-axis
2 → y-axis
3 → z-axis
Typically, the poling direction aligns with the z-axis.
When working on a 2D model, you need to specify the desired plane using one of the six available coordinate systems: XY, YZ, ZX, YX, ZY, or XZ.
I recommend using the default XZ coordinate system, which aligns the x and y axes in the 2D model with the original x and z directions in the 3D coordinate system of the material properties.
Please note that for 2D structural modeling, you must choose between the plane-stress or plane-strain assumptions. Additionally, please be cautious about removing elements of the coupling matrix (d) for reduction purposes, as this may lead to errors in your analysis.
Regards,
Milad
Your message is clear and professional! Here's a slightly refined version to enhance readability and flow:
Hello,
The default directions of piezoelectric material properties in the built-in COMSOL material library (in 3D space) are as follows:
1 → x-axis
2 → y-axis
3 → z-axis
Typically, the poling direction aligns with the z-axis.
When working on a 2D model, you need to specify the desired plane using one of the six available coordinate systems: XY, YZ, ZX, YX, ZY, or XZ.
I recommend using the default XZ coordinate system, which aligns the x and y axes in the 2D model with the original x and z directions in the 3D coordinate system of the material properties.
Please note that for 2D structural modeling, you must choose between the plane-stress or plane-strain assumptions. Additionally, please be cautious about removing elements of the coupling matrix (d) for reduction purposes, as this may lead to errors in your analysis.
Regards,
Milad
Please login with a confirmed email address before reporting spam
Posted:
6 months ago
31 dic 2024, 22:47 CET
How do I specify the desired plane? What significance is the ordering of the 6 planes systems?
The motivation for removing elements of the coupling matrix is to make the results simpler to understand. My immediate goal is to demonstrate a 1D "piezo spring" by two methods.
- A 2 dimensional simulation with variation in only 1 dimension. I wish to create an artificial material properties such that the piezo coupling is simplest: a single non-zero element in the coupling matrix. I expect the eigenmodes to be simple enough also. The lowest order mode will be half a wavelength across the dimension of variation, and there will be harmonics above that.
- A 1D dimensional simulation using Coefficient Form PDE. COMSOL does not support piezo multiphysics in 1D. I should get the same results as the 2D simulation described already. This model is attached. I have the PDEs setup but I am still working on how to understand the boundary conditions, studies, and results. I don't understand how to constrain the left side of the interval, while the rest of the interval is free to shrink and expand. I want to plot the time domain solution of the some points along the interval.
For both simulations, I want to back out the ideal material electro-mechanical coupling coefficient via measurement, which should be a function of the material properties. If they match, I have confidence in more realistic and complicated resonator design simulation results.
How do I specify the desired plane? What significance is the ordering of the 6 planes systems?
The motivation for removing elements of the coupling matrix is to make the results simpler to understand. My immediate goal is to demonstrate a 1D "piezo spring" by two methods.
1. A 2 dimensional simulation with variation in only 1 dimension. I wish to create an artificial material properties such that the piezo coupling is simplest: a single non-zero element in the coupling matrix. I expect the eigenmodes to be simple enough also. The lowest order mode will be half a wavelength across the dimension of variation, and there will be harmonics above that.
2. A 1D dimensional simulation using Coefficient Form PDE. COMSOL does not support piezo multiphysics in 1D. I should get the same results as the 2D simulation described already. This model is attached. I have the PDEs setup but I am still working on how to understand the boundary conditions, studies, and results. I don't understand how to constrain the left side of the interval, while the rest of the interval is free to shrink and expand. I want to plot the time domain solution of the some points along the interval.
For both simulations, I want to back out the ideal material electro-mechanical coupling coefficient via measurement, which should be a function of the material properties. If they match, I have confidence in more realistic and complicated resonator design simulation results.