Please tell me
What is characteristic time in Fourier number?
How can I calculate characteristic time?
Suppose I started heating water in a closed container by immersion rod. And and temperature increases continuously,. Suppose at time, $t=260 sec$ temp. at center is $40^oC$, and at $t=480 sec$, center temp is $42^oC$. Then toHow do I calculate Fourier number I need characteristic time.
- Then which time I should consider, $263$ or $480 sec$?