Pig Simulation: Failed to create heat source field extractor
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This error message is for the Acoustic simulation. Maybe you haven't run the Thermal simulation? You need to run the Thermal simulation first and this needs to have results before you can run the Acoustic simulation which uses the results from the thermal simulation
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I updated the pig simulation with a Yasoon simulation. If I run the thermal simulation first I get an error message to run the acoustic simulation first, the thermal simulation. Also, the transcranial focused ultrasound tutorial uses the acoustic simulation first.
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Yes. The source settings are shown here.
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The file is 3 GB. If you send me your email address, I can share a link with Microsoft Onedrive and you can access it online.
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I do not know where to find the input file. I have one file that contains the entire project.
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Here is a link to the .smash file.
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I think I must link your email address to share the .smash file.
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I added your email to the OneDrive link. You should receive an automated email.
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Here is snapshot for the animation of the pressure field. The video is too large to upload.
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Ohh I see what the issue is now ...
You need to have results in the frequency domain (steady state). It then uses this steady state result to heat the tissue
The thermal solver uses the dP/dV field (deposited energy) from the acoustic solver as an input. Since your results are only in the time domain, then this field is not available (you can check it yourself by a) looking at your Field Sensor Settings with Overall Field and see that your recording domain is only in Time Domain ... and b) when you extract Acoustic results, you only get p(x,y,z,t) and you don't get p(x,y,z,f) or dP/dV)
You should therefore change your recording domain to "Frequency Domain" or "Frequency and Time Domain"
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Some other notes about your simulation setup that should be useful
- For the acoustic simulation you will need a much higher resolution - To get an idea, you are stimulating at 1 MHz and your wavelength will be approximately 1500 (speed of sound in water) / 1 MHz = 1.5 mm (your current discretization is 3mm, way too course)
- You don't need to simulate the whole body, since the field will be localized near your target, you can limit the domain to a much smaller area encompassing the transducer and the nearby tissues directly under it (after your simulation just make sure the field near the boundaries are relatively small)
- Get rid of air and replace it with water if possible / appropriate. The time step used in the simulation is limited by the lowest speed of sound in the simulation domain (water = 1500 m/s, air = 300m/s). I'd recommend changing the background material to water (as you already do) and getting rid of the air in Yonsoon and replacing by water (this shouldn't be a problem)
- Thermal simulation are you sure you're using the correct simulation time? You seem to be heating it for 1microsecond only
- Again you can maybe limit the simulation domain, but maybe you don't need to since you don't need that fine a discretization as you would for the acoustic simulation
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I also noticed that your transducer is composed of a source element and a reflector, to ensure you don't get back reflections you should set your reflector as a reflector (create new material property -> drag and drop reflector -> select Reflector in materials settings) and make sure the reflector is not in source settings
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Performing the simulation with both frequency and time domain solved the previous error.
Now, I am limited by the student license for the size of the number of cells I can simulation. I must reduce the grid size to get a better resolution. However, I cannot adjust the Boundary- and Boundary+ settings in the main grid.
For the thermal simulation time, I was only simulating for a very short time to debug the system until I could get the thermal solver to work. I plan to increase the simulation time after adjusting the grid volume to a smaller region.