On Mon, 26 Feb 2007 dgbj_at_aol.com wrote:
> This temperature difference would make a 4 or 5 percent difference in energy
> (about 0.3% per Fahrenheit degree). The energy relations for rubber must be
> calculated on an absolute temperature scale. There is not a 15% energy
> difference between the temperatures you mentioned.
Wrong. The figures that I quoted were normalized from the slope parameter
of the regression model fitted to measured data (also other data points
than 15C and 30C). For a regression model it makes no difference where the
zero point of the temperature scale lies, any interval scale on X-axis
(the independent variable) will do. The 10% difference in energy return
between 15C and 30C is a correct value, and is actually observed in the
measured data, not just derived from the regression model. It may be
questioned, however, for what temperature range the reduction of the
energy return remains linear. Definately this will NOT apply down to
absolute zero, and also the increase in energy return will saturate
somewhere between 30 and 40C, above which the rubber will get too soft to
store the energy.
-Tapio-
Received on Mon Feb 26 2007 - 03:15:17 CET
This archive was generated by Yannick on Sat Dec 14 2019 - 19:13:44 CET