[Vo]:Takahashi clarifies calorimetry stirring problem

[Jed Rothwell]

In earlier reports I expressed concern about the calorimetry employed 
by Kitamura et al. The flow rate of the cooling fluid is 6 ml per 
minute. This seems too low to me. Most people I know who use flow 
calorimeters recommend at least 30 to 60 ml per minute. At 6 ml I 
fear the fluid is not mixed and the temperature sensor may pick up a 
streamline of warm or cold water.

I discussed this with Takahashi. He says there is a mechanical mixer 
to ensure a uniform fluid temperature at the temperature sensors. 
This is not shown in the schematic, but the schematic is somewhat abstract.

Takahashi points out that the low power levels in this experiment, a 
faster flow rate will reduce the sensitivity of the experiment too much.

Other researchers use methods to ensure mixing that depend upon the 
motion of the fluid, or the pressure. McKubre used a Venturi, and 
Cravens has some in-line corkscrew shaped plastic stirrers. These 
would not work at 6 ml/min. A mechanical stirrer should work fine.

- Jed