Mattia Rizzi <> wrote:

Another good question: why was used so [high]  water flux? Why not reduce
> the water flux and get 30-40 degrees  Celsiusof difference instead of 4-5
> degrees?

Two reasons, I think:

1. Safety. You want to be sure the heat will be removed even if it
increases a great deal, the way it did on Feb. 10.

2. Most people I know who do a lot of calorimetry prefer a smaller Delta T,
between 5 and 10°C. They prefer to keep the absolute high temperature below
~30°C. Above that you get problems with the fluid characteristics changing,
and the conversion rate of 4.12 J = 1 cal. starts to change a little.

There is no difficulty measuring a difference of 5 and 10°C. There is no
chance of a mistake. With modern instruments you can measure a difference
100 times smaller (0.1°C) with absolute confidence. The signal-to-noise
ratio is not enhanced much by going to a 30°C difference.

- Jed

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