Why Traditional Hot Plate Methods Fail?
- In the hot plate method, the heat travels through the sample and is measured as a delta temperature on the other side.
- For high conductivity materials, this is fine, but for highly insulating materials, this means that very little heat makes it through, resulting in a weak signal.
- If the resulting delta temperature is then similar in size to the error in the temperature measurement, this can lead to 100% uncertainty in measurement result.
- One solution to this problem is to significantly turn up the heat on the hot plate, resulting in higher delta T across the sample and a larger signal to be measured on the other side.
- However, this then requires much longer times to reach steady state (increased costs) and can result in significant convection & radiation, where the heat loss may be similar to the conducted heat, again resulting in larger measurement errors.