| Topic: |
Science > Physics |
| User: |
"Andy Resnick" |
| Date: |
22 Sep 2006 08:27:55 AM |
| Object: |
Re: Liquid Level Sensor: How ? |
Robert11 wrote:
<snip>
Any thoughts on how they know if the liquid is empty in the chamber ?
Could it be as simple as if the solenoid has actuated, opening the
container, it is assumed that the container is empty?
Does the fluid container have a reservior somewhere in the door that
could have additional (unseen) circuitry? Does the fluid actually meter
out? If so, it could be something simple like a balance that monitors
the mass of the reservioir.
--
Andrew Resnick, Ph.D.
Department of Physiology and Biophysics
Case Western Reserve University
.
|
|
| User: "" |
|
| Title: Re: Liquid Level Sensor: How ? |
22 Sep 2006 08:03:29 PM |
|
|
Absolute knowledge of liquid height is an importent topic. Reliable
sensing
is non trivial.
A new style is present for consideration.
Always force test the surface. And the common float force, tests.
Making the sensor a float replacement technology. And here I recommend
something like ultrasound. A sensor at the top to look down into the
canister.
Cheap sensors are likely on the internet of this class.
A failure of distance means a kind of force discrepancy. A false image
would be the true failure and once the image is obtained, a loss of
image or force reply of anykind fails the sensor.
And so bad distance is a validity test for the depth of the true
canister. And then statistical testing of sets of data allows the
confidence level of the value to be obtained.
So I say, go ultra sound.
Andy Resnick wrote:
Robert11 wrote:
<snip>
Any thoughts on how they know if the liquid is empty in the chamber ?
Could it be as simple as if the solenoid has actuated, opening the
container, it is assumed that the container is empty?
Does the fluid container have a reservior somewhere in the door that
could have additional (unseen) circuitry? Does the fluid actually meter
out? If so, it could be something simple like a balance that monitors
the mass of the reservioir.
--
Andrew Resnick, Ph.D.
Department of Physiology and Biophysics
Case Western Reserve University
.
|
|
|
|
| User: "cnctut" |
|
| Title: Re: Liquid Level Sensor: How ? |
22 Sep 2006 06:15:21 PM |
|
|
Andy Resnick wrote:
Robert11 wrote:
<snip>
Any thoughts on how they know if the liquid is empty in the chamber ?
Could it be as simple as if the solenoid has actuated, opening the
container, it is assumed that the container is empty?
Does the fluid container have a reservior somewhere in the door that
could have additional (unseen) circuitry? Does the fluid actually meter
out? If so, it could be something simple like a balance that monitors
the mass of the reservioir.
--
Andrew Resnick, Ph.D.
Department of Physiology and Biophysics
Case Western Reserve University
Andy,
Were you able to come up with a solution to your "Q: Drag force on a
cylinder" problem? Would be interested in the thought matrix for the
solution at the R numbers you were concerned with.
Thanks,
Tut
.
|
|
|
| User: "Andy Resnick" |
|
| Title: Re: Liquid Level Sensor: How ? |
25 Sep 2006 08:27:47 AM |
|
|
cnctut wrote:
Andy Resnick wrote:
<snip>
Andy,
Were you able to come up with a solution to your "Q: Drag force on a
cylinder" problem? Would be interested in the thought matrix for the
solution at the R numbers you were concerned with.
Sort of- I found the original derivaton in Lamb's "Hydrodynamics" (more
detail in the 'A: Drag force on a cylinder' thread. It's not simple...
blech.
--
Andrew Resnick, Ph.D.
Department of Physiology and Biophysics
Case Western Reserve University
.
|
|
|
| User: "cnctut" |
|
| Title: Re: Liquid Level Sensor: How ? |
25 Sep 2006 05:26:07 PM |
|
|
Andy Resnick wrote:
cnctut wrote:
Andy Resnick wrote:
<snip>
Andy,
Were you able to come up with a solution to your "Q: Drag force on a
cylinder" problem? Would be interested in the thought matrix for the
solution at the R numbers you were concerned with.
Sort of- I found the original derivaton in Lamb's "Hydrodynamics" (more
detail in the 'A: Drag force on a cylinder' thread. It's not simple...
blech.
--
Andrew Resnick, Ph.D.
Department of Physiology and Biophysics
Case Western Reserve University
Andy,
I figured it might be a good thought problem/solution--that's why I
asked. Are you saying I should save my money and pass on Lamb's book?
;-))
VR
Tut
.
|
|
|
| User: "Andy Resnick" |
|
| Title: Re: Liquid Level Sensor: How ? |
26 Sep 2006 08:29:47 AM |
|
|
cnctut wrote:
Andy Resnick wrote:
<snip>
Andy,
I figured it might be a good thought problem/solution--that's why I
asked. Are you saying I should save my money and pass on Lamb's book?
;-))
Heh... no, I guess it is a great problem to try and figure out. I
learned a lot by just translating it into modern notation. The book is
only about $20, so I guess it depends on how much your
effort/frustration is worth. No way I could have figured it out on my own.
--
Andrew Resnick, Ph.D.
Department of Physiology and Biophysics
Case Western Reserve University
.
|
|
|
| User: "tj Frazir" |
|
| Title: Re: Liquid Level Sensor: How ? |
26 Sep 2006 09:34:59 AM |
|
|
Use a clock or be wrong 99 % of the time.
How long you let water pass a point is the best way .
In a ship the ballast clock and records will measure how much water is
in the 500 x 90 foot cylinder.
In a 1/2 inch pipe 200 feet into the ground
has no other methods known to work.
Air psi blast the water out the bottom untill the pipe is empty or
against a set psi.
Then the water going up to level will displace a measurable amount of
air out the top at the time water moves up the pipe.
If you know how long that pipe is and knocked the air out you can clock
how long the air going out is .
Ill put a henged flap out of paper on the top of the pipe after I blow
the water out and clock
how long it has air pushing the flap up .
I then set a chart of clock times and ppe sizes to use against a stop
watch.
You can make off the wild gesses but can you biuld anything that works
?
Try THIS TRY THAT wount allways save yer *****.
Some times it takes dicected practical old fasion science one prossess
at a time like evrything else is biult.
.
|
|
|
|
|
|
|
|
|
Related Articles |
|
|
