Mattia Rizzi <mattia.ri...@gmail.com> 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