 Mon Dec 16 21:32:21 2024, Luis, Update, VAC, MR Testing 
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[Luis, Luke]
The MR material was placed in the vacuum chamber following standard procedures to ensure the vacuum remained as clean as possible.
During this process, we only opened the main
volume while keeping the gate valve between the two volumes closed to maintain the UHV in the RGA section.
An
RGA scan was taken before this process, this will be used to compare the state of the vacuum with the sample inside to determine whether the MR material |
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Tue Dec 17 13:53:53 2024, Luis, Update, VAC, Vacuum system status
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[Luis]
The vacuum system is being baked. I disconnected the digital gages and the magnets, opened the Ar leak and started the bake by taking
the temperature from 60C-90C-125C waiting about 15-20 minutes between each interval. The RGA electronics were left on since the temperature of the flange
was 36.6C (bellow the 60C threshold) |
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Thu Dec 19 12:00:44 2024, Luke, Update, VAC, End of bake
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The vacuum chamber has stopped baking.
Current state as of 11:40, 12/19/2024:
The gate valve is open, and the filament of the RGA is on. |
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Sun Dec 22 20:43:35 2024, Luis, Update, VAC, MR Testing
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[Luis, Luke]
RGA Volume: T = 23°C, P = 3.0e-9 Torr
Main Volume: T = 22°C, P = 9.90e-9 Torr
After letting the vacuum cool down for a couple days, we reattached the magnets and sensors, then we performed a RGA scan of the vacuum system, |
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Thu Jan 2 17:52:58 2025, Luis, Update, VAC, MR Testing Continuation
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[Luis, Luke]
RGA Volume: T = 22°C, P = 2.10e-9 Torr
Main Volume: T = 21°C, P = 5.71e-9 Torr
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Fri Feb 7 12:25:56 2025, Luke , Summary, VAC, Started bake
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[Luke, Luis]
The vacuum chamber is currently baking.
We stepped up to 120°C by increments of 30°C starting at 60°C. We took about an hour break at 90°C to let the temperatures equilibrate. |
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Tue Feb 11 08:07:02 2025, Luis, Update, VAC, Bake stopped
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[Luis, Ma]
Feb/10/25 4:00pm
Bake was stopped. |
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Fri Feb 14 11:57:50 2025, Luis, Update, VAC, Vacuum Update
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[Luis]
Feb/11/25 9:30am
Pressure gages were connected. |
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Fri Feb 14 12:15:23 2025, Luis, Update, VAC, Vacuum sytem staus
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[Luis, Luke, Ma]
February 12, 2025 - 4:00 PM
We performed an RGA scan with the vacuum system containing the heater elements. The results are attached below. |
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Tue Feb 18 11:19:13 2025, Luke , Configuration, VAC, Repositioning of the lid's temperature probe
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Before the recent bake I slightly repositioned the temperature probe on the lid from beside the heater tape to under the heater tape. This was done to better
know and control the temperatures of the chamber while baking. It has appeared to work with the temperatures being held very close to the 120C target.
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Thu Feb 20 17:07:36 2025, Luis, Update, VAC, RGA Scan
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[Ma, Luis]
February 20, 2025 - 3:30 PM
Ma performed an RGA scan with the vacuum system containing the heater elements. The results are attached below. |
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Mon Feb 24 17:50:13 2025, Luis, Update, VAC, RGA Scan
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[Ma, Luis]
February 24, 2025 - 1:00PM
Ma performed an RGA scan with the vacuum system containing the heater elements. The results are attached below. |
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Mon Oct 3 17:21:39 2022, Cao, Update, TCS, Inspection of macor parts 7x
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The macor parts arrived and inspected today. These include:
Macor spacer (drawing: LIGO_Redesign_Macor_Spacer_Drawing_v4.pdf
attached below), quantities: 40
No defects, damages observed
Parts are free from grease/ machining fluid
Wall thickness
of 1 mm appear to provide sufficient stiffness to part
Images of parts: Macor_spacer_0.jpg, Macor_spacer_1.jpg
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Thu Jul 27 10:18:43 2023, Celeste, Update, TCS, Graphical Updates to HOM RH Modification
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| Attached are updated graphs of the irradiance distribution from the 1/8th ring heater units (extruded and reduced in length). |
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Fri Jul 28 17:45:45 2023, Celeste, Update, TCS, Graphical Updates to HOM RH Modification, Friday 7/28
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| Updated 1/8th Heater simulation modification graphs. Slides 7, 10, 16-19 are new additions. |
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Tue Aug 1 16:22:35 2023, Celeste, Update, TCS, Graphical Updates to HOM RH Modification, Tuesday 8/1
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| Slides 20-33 are newly added (data/graphs from parameter sweep feature-1/8th heater unit length varied from 10% of original to 100% of original). |
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Thu Aug 10 14:13:38 2023, Celeste, Update, TCS, 8/10/23, Simulation Graphical Progress
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Fri Aug 11 10:57:20 2023, Celeste, Update, TCS, 8/11/23 Simulation Progress
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Tue Aug 15 16:10:06 2023, Celeste, Update, TCS, 8/15/2023 Simulation Progress
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Mon Dec 11 16:20:17 2023, Jon, Summary, TCS, FROSTI Assembly Procedure
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Below is the procedure we will follow to assemble the FROSTI prototype.
Install SS guide rods and bottom Macor spacers in bottom reflector
Install AlN elements on top of bottom Macor spacers
Install
upper Macor spacers on top of AlN elements
Feed unterminated power and RTD leads through slots in upper reflector
Install upper reflector, |
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Mon Feb 26 21:23:27 2024, Jon, Update, TCS, FROSTI Assembly - Day 1 7x
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[Jon, Tyler, Luis, Luke, Mohak, Cynthia, Michael, Aiden]
FROSTI assembly began today. After a final set of RGA scans were taken, the vacuum chamber
was vented and the reflectors were removed. The chamber was then resealed and pumped down again.
Today we completed the installation of the Macor hardware and heater elements between the two reflector halves. Tomorrow we will route, bundle, |
 Wed Feb 28 17:49:18 2024, Tyler, Update, TCS, FROSTI Assembly - Days 2-3
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[Aiden, Jon, Luis, Luke, Michael, Tyler]
FROSTI assembly was completed today. The RTD and power wires were terminated at the DB-25 connectors and
the legs were put on. It is currently placed in front of the stand-in test mass (~5 cm away). The FLIR has also been moved back to it's nominal position.
As of now, it appears there are some shorts within the power cabling. This will be a focus of tomorrow's work.
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Wed Mar 6 09:57:52 2024, Tyler, Update, TCS, FROSTI Wiring
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Upon finishing the FROSTI assembly last week, we ran into some electrical issues. An electrical short was found between two of the d-sub pins (2 and
8). It appears that the pins were somehow coming into contact with the aluminum surrounding them. This was causing the power supply to trip. The issue
was seemingly fixed by adjusting the positioning of the cabling leading out of the reflector. When handling the device in the future, please make sure |
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Mon Sep 16 14:59:51 2024, Tyler, Update, TCS, FLIR RIN Update 09/16
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Below is the dark noise spectrum of the Red Pitaya, which was measured over the course of a weekend. Additionally, I have successfully measured a signal
from the photodetectors with the FROSTI as the IR source, so it seems there shouldn't be any worry of these particular detectors not being feasible for
the RIN measurement. |
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Wed Oct 2 12:20:43 2024, Tyler, Update, TCS, Updated FROSTI Analysis 10/02/2024
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| Attached below are updates on current FROSTI prototype analysis. |
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Wed Oct 9 13:52:31 2024, Tyler, Update, TCS, RIN Update 10/09/2024
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I tried adjusting the gain settings on the photodetectors to check if this would help improve the RIN spectra measurements. Overall, it doesn't look
like it does, and if anything, looks worse. I assume this is so because as the gain is lowered, the amount of detectable signal from the FROSTI becomes
smaller and smaller. |
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Wed Dec 18 15:41:56 2024, Tyler, Update, TCS, FROSTI RIN
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[Tyler]
I have begun the (hopefully) final RIN measurements at 3:30 PM today. If you need to go into the cleanroom at any time between now and Sunday
(the 22nd), please do not touch the FROSTI, the Red Pitaya, the photodetectors, or any of the wiring. |
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Mon Dec 23 14:33:36 2024, Tyler, Update, TCS, Latest RIN Measurement Results
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| Attached below are the measurements I took from the FROSTI from 12/18-12/22. |
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Tue Jan 14 10:27:14 2025, Tyler, Update, TCS, RIN Updates
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[Tyler]
Attached below are updated plots for the FROSTI RIN measurements for Jan 14 group meeting.
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Fri Jan 17 13:27:07 2025, Tyler, Update, TCS, FROSTI Pre-disassembly
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[Tyler, Ma, Cece, Jon, Luke, Cynthia, Michael]
On Tuesday, we prepared the FROSTI for disassembly in anticipation of the APS filming that is set to
take place in the labs. The FROSTI has been unbolted from the optical table in the cleanroom, with its wires weighted down and the majority of its screws
removed to ensure an easy removal of the reflectors during the filming process.
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Wed Jan 22 10:50:08 2025, Tyler, Update, TCS, FROSTI Disassembly
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[Tyler, Ma, Cece, Luis, Shane, Luke, Cynthia, Liu, Jon]
On Tuesday (Jan 21), we took the FROSTI apart in front of a filming crew. It was a success!
The footage is going to be used in an APS video detailing the experimental cosmology research conducted in the department.
The FROSTI reflectors, heater elements, and legs were all bagged separately and a currently being stored in the cleanroom. If you need to do |
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Tue Feb 18 10:12:39 2025, Tyler, Update, TCS, Final RIN Plot Update
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Below is a preview of the final RIN figure that will be included in the FROSTI instrument paper. A quick summary of what is shown below:
The original RIN CSD measurement is shown on the top panel in red. Frequency bins that exhibit external electronics noise (ex. ADC, photodetector
noise, etc.) are identified and shaded in gray. These noisy bins are then excluded from the dataset before beginning the next step in the analysis process: |
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Tue Mar 4 10:28:58 2025, Tyler, Update, TCS, RIN Plot Updates
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Tue Mar 25 12:56:47 2025, Tyler, Update, TCS, FROSTI Analysis Finalization
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Upon final review of the FROSTI analysis included in the (hopefully) soon-to-be submitted instrument paper, I've made some adjustments to the reflectivity
analysis that estimates the amount of power delivered to the test mass by the FROSTI. Initially, as detailed in elog
447, the delivered power was approximated to be 12.6 W (later adjusted to 12.9 W), with roughly 18% of this power being reflected by the test mass. |
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Tue Jul 18 14:13:46 2023, Sophia , Update, Scripts/Programs, Update on Laser Noise Data Collection and Analysis 6x
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We [Sophia and Tyler] have found a code which will partition our data and generate PSD's and CSD's automatically. We are now in the stage of writing this
into a dynamic code, which so far has been fast-paced because of the framework we have built for it over the past few weeks.
Something to note is that
we have found, especially over long periods of time, the laser goes through periods of extreme noise and the signals often cross from where we set them |
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Thu Jul 27 11:28:36 2023, Sophia , Update, Scripts/Programs, Update on Laser Noise Data Collection and Analysis: Dynamic CSD and PSD Plots
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This week I have successfully been able to implement our dynamic CSD and PSD plotting code, but along the way I encountered a few challenges which I will
outline in this elog post.
Challenges:
1. Once I was able to plot the data through time, I produced a graph of the raw data (shown below in the top
to images) which showed pulsed data instead of a continuous stream. On Tuesday (26th of July) Tyler and I fixed this issue, realizing that calling the |
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Thu Jul 27 14:11:42 2023, Sophia, Update, Scripts/Programs, Update on Laser Noise Data Collection and Analysis: Dynamic CSD and PSD Plots
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Here's a screen recording of the dynamic raw data and PSD/CSD plots as they are now. Will begin working on implementing a code to generate the statistical
estimator for the CSD uncertainty now. (Will talk to Tyler more about whether I can get the lines to happen or not) |
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Mon Jul 31 19:27:30 2023, Sophia, Update, Scripts/Programs, Update on Laser Noise Data Collection and Analysis: Dynamic CSD and PSD Plots
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An update on the CSD/PSD code:
The code is now taking a dynamic average of the points, and that has significantly reduced the noise that we were reading
and the issues I was having with the lines in the plots. The graph for the CSD is still putting up a fight though, and amassing many lines that do not
appear when just scatter plotted. I plan to fix that tomorrow, alongside inserting my own generated signal into the data. I have plotted the coherence |
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Tue Aug 1 15:44:31 2023, Sophia, Update, Scripts/Programs, Update on Laser Noise Data Collection and Analysis: Dynamic CSD and PSD Plots 6x
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We have identified two problems facing the intensity noise calculations, which we are working to solve.
The first of these problems, is that the red
pitaya appears to be taking data approximately 4 times faster than we would expect from the decimation rate based on how quickly it runs. To see if this
was affecting our data, we plugged the red pitaya into a function generator. We found that my code is able to identify the driving frequency, but consistently |
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Mon Aug 7 15:36:18 2023, Sophia, Update, Scripts/Programs, Update on Laser Noise Data Collection and Analysis: Dynamic CSD and PSD Plots 7x
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Today I was able to fix the red pitaya's plotting problem, and get my code to recognize driving frequencies from the function generator to within a 0.5
Hz estimation. The sinusoidal plots I have included are from sending a 1 Hz signal into the red pitaya to see the signal in real time. This allowed me
to see exactly where the system was messing up, and fix from the ground up. Once I had that working, I began to test sending in frequencies in the range |
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Tue Aug 8 16:47:11 2023, Sophia, Update, Scripts/Programs, Update on Dynamic CSD and PSD Plots
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We have fixed our rapid plotting error, and realized that this has not been affecting our data intake! Below is a video of the code progressing, alongside
grabbed images of the raw data. The data is now continuous, and performs as we expect. Next, I plan to add a widget which will dynamically show the peak
values instead of them just being printed in the terminal after each iteration. (Ignore the red box-- it was from me struggling with a now fixed issue). |
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Tue Aug 15 10:35:00 2023, Sophia, Update, Scripts/Programs, Update on Laser Noise Data Collection and Analysis: Dynamic CSD and PSD Plots
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I have successfully added a button to my graphics, but it has posed a strange issue with the CSD and PSD values. When I plot my original code, I still see
the pretty peaks that I was getting originally, while my new code (as shown in the video and in the last screenshot) is giving me more of a line. In my
code that gives the peak values, the CSD values also tend to fluctuate in this new code as well (shown in the first screenshot), before returning to the |
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Tue Aug 15 13:32:37 2023, Sophia, Update, Scripts/Programs, Update on Laser Noise Data Collection and Analysis: Dynamic CSD and PSD Plots
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I have now fixed all issues that I was having this morning, and have added text boxes which show the peak values of both PSD's and the CSD alongside the
graphs. They also update continuously with the graph. This is shown in the top image. The laser was driven at 400Hz, and had 0.5V peak to peak voltage,
both of which appear correctly in the below graphs.
Now that the code is almost fully working (we will finish debugging the screenshot method later |
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Mon Oct 30 11:03:56 2023, Tyler, Update, Scripts/Programs,
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FLIR: After some adjustments, the plot generated from the FLIR measurements look much more symmetric (see attachment). There are more included grid
points, which smooths out the curve as compared to last week.
Red Pitaya: It looks like a new OS update was released for the RP, which includes
a new Python API (was previously only available in C). I'm going to try and update the one we have currently running in lab.
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Tue Feb 6 22:40:25 2024, Michael, Update, Scripts/Programs, Long Crab 1 Design Created In Gtrace
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Worked on and completed the python code for the simulation of the Long Crab 1 layout for Cosmic Explorer basing off of Pooyan's original work with the Crab
1 layout. From here I'll look into creating the shoelaces layouts. |
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Fri Jun 14 13:32:13 2024, Liu, Update, Scripts/Programs, COMSOL simulation on rectangular heater elements design 6x
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I have been looking at the feasibility of an alternative heater element design for FROSTI that replaces the original ring-like heater elements with n
rectangular elements with straight edges. They form an n-sided regular polygon that could well approximate the original annular ring if n is large enough.
This eliminates curved surfaces requirement for the heater elements, which was the source of the many month production delay for the prototype parts. |
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Fri Jun 21 11:47:30 2024, Liu, Update, Scripts/Programs, COMSOL simulation on alternative straightened heater elements design 6x
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In the previous post, we saw that for the heater element design with straight
edges in replacement of the current eight-element ring-like design, it provides the similar Gaussian-like irradiance profiles, but with smaller power delivery
efficiencies, as shown in the plot. This turned |
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Thu Jun 27 11:09:14 2024, Liu, Update, Scripts/Programs, Straight edge STEP files and ray loss analysis
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Drawings and CAD models of the straight-edge designs are exported, and are visualized in SOLIDWORKS. Two are attached. One is a single edge of the evenly
spaced polygon design with 16 edges, and the other is the 8x2 design, with two neighboring edges grouped together to replace the original single curved
heater.
For the straight edge design in COMSOL, ray power detectors were placed at the heater's front surface. The irradiance is shown in |
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Mon Sep 23 15:11:21 2024, Tyler, Update, Scripts/Programs, Effective Emissivity Analysis and RIN Update
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A quick update on the effective emissivity analysis for the CIT FROSTI testing:
I was able to (roughly) match the OPD data to a referenced COMSOL model, with an applied power of 12.6 W (as seen below). However, when changing
the emissivity of the ETM in COMSOL, the dT profiles do not seem to change much. I am not sure as to why this is the case at the moment, and will continue |
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Sun Feb 23 16:00:07 2025, Luke , Update, Scripts/Programs, Ringheater modeling Update
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These are some plots:
The first shows the convergence of the 02 mode reducing the size of the mesh. The second shows the the numerical error of the zernike.
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