Sounds like one of Rossi's controllability issues may come from the
temperature stability of the cooling fluid itself.
Dave's explanation sounds as if the control loop is expecting a rather
consistent cooling fluid inlet temperature... and that may be the case
if running off the city water supply (at least no major differences in
water temp for a running faucet), but if one gets a sudden drop of
several degrees on inlet water temp, what will that do to the control
loop???
-Mark Iverson
On Thu, Jan 2, 2014 at 10:33 AM, Jones Beene wrote:
From: David Roberson
Could you offer a simple description of the behavior of the negative
differential resistance function that you mention?
Looks like you are already doing something similar. Wiki has an entry
for the electronic version. The image of the curve is an ascending
double hump, so if your model accommodates that already, then that may
be why it is so intuitive. If one is plotting P-in vs. P-out then there
is good control functionality to the top of the first hump, where the
negative feedback would start to show itself.
https://www.google.com/search?q=negative+differential+resistance&client=firefox-a&hs=bBT&rls=org.mozilla:en-US:official&tbm=isch&tbo=u&source=univ&sa=X&ei=JKTFUo6jBcvxoASVpoCABw&ved=0CDwQsAQ&biw=1146&bih=675
