On Oct 12, 2011, at 6:36 AM, Andrea Selva wrote:
So why, as suggested by many, he didn't use another kind of
flowmeter so we could have now instantaneous values to plot along
the temperature ones ?
Couldn't he afford it ? He sold home !
Having such data we could have explained the apparent instability
and crazyness of the output power curve.
Probably not, if the two existing meters were replaced. The input
flow was likely steady. However, it is true, an extra water meter
located at the primary circuit exit of the heat exchanger would have
been very informative.
Flow meters were used but apparently no one thought to record time
stamped volume data. It is much more accurate, depending on flow
variations, to calculate flow f(t) from volume v(t) as:
f(t) = d V(t)/dt
than to integrate:
V(t) = integral f(t) dt
(or a similar integration to obtain energy) using occasional sporadic
short interval flow measurements. This is the value of using volume
meters. Because they monitor continuously, they catch brief
excursions that might otherwise be missed.
Unfortunately the flow meters were ignored.
Best regards,
Horace Heffner
http://www.mtaonline.net/~hheffner/
