Unconventional electrolysis

  • I noticed that radiation instrumentation readings are frozen. Water temperature has also remained to 108.1 °C for a while.


    The labjack USB connection shut down, so the data stopped updating. Another detail to fix, but the audio and power monitoring worked OK.

    Regarding the resonant noise, it was clearly related to a series of short (100 usec) discharge events as shown on the scope. There was also some fireworks visible on the camera image of the cell, though dimmed by the nearly-opaque electrolyte.

  • magicsound

    It seems as if the noise could be electrolyte temperature-dependent. It could be due to cavitation bubbles forming and collapsing back before reaching the surface. Water is known to produce more noise when it's close to boiling rather than completely boiling, so it could be related with this effect. How this relates to the discharge events is not clear, but it could indicate that temperature control is desirable.


    https://engineering.stackexcha…different-phenomena/12001




    EDIT: here a screenshot of discharge events at 15:15:14 as displayed in the now ended live stream video.


  • The video is available for playback at https://www.youtube.com/watch?v=DO7R_Kk2hFg


    The cell starts singing at 15:13 on the red in-display time. I agree the onset seems to be somewhat temperature-related. As to the cause, it is related to a train of short (~100 usec) pulses seen on the scope display as shown above, so it isn't just boiling-related. See the region starting at 15:15. The audio frequency is correlated with the pulse interval of about 1 msec. This is very good data to have.


    For reference, the scope horizontal axis is 1 msec/division and the vertical is 5 volts/division.

  • magicsound

    It looks like something strange with electrolyte temperature happened just before the noise subsided for the most part (at 15:19:34). The full data could clarify this (I sampled the points manually from the video). The 108.1 °C temperature from 15:27:13 seems to be a glitch.


  • Yeah, I saw that. Here's the error log from the software that runs the labjack. I think its USB interface froze or maybe there was a glitch from one of the input lines or from RF noise. The control program's Python error log shows a failed read attempt:


    AIN1_EF_READ_A Labjack read_variable Error, 19 23:27:21

    File "C:\Users\DELL\Dropbox\MFMP_Python\MFMP Oct 2018 v7\mfmp_labjack.py", line 225, in read_variable

    variable = ljm.eReadName(self.handle, port)

    File "C:\Python34\lib\site-packages\labjack\ljm\ljm.py", line 567, in eReadName

    error = _staticLib.LJM_eReadName(handle, name.encode("ascii"), ctypes.byref(cVal))