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Verifying thermistor chain and conducting hot fin heat transport

Warm Source Heat Transport
Set up:
Open horizontal GREC consisting of BottomLayer plate with boundary Shells, MidLayer with 10 thermistors type pt500 (see layout sketch below) and a two disk Revolving Shutter (RS) parked in a position with the Work Generating Volume (WGV) opening standing still in the "Nil-position" paired with the Conducting Cold Fin.

Using some IKEA Värmeljus candles under the hot fins and triggering measurements manually by passing a hall-sensor over the position magnet in the Revolving Shutter. The DynamicLink software logged something like 40 readings during 2385 seconds i.e. roughly 40 readings during 40 minutes and is presented below as a graph.
MOTORlog202009-105538.jpg


The graph shows that the heat travels steady in the aluminium of the heat conducting fin from the peripheral heat sensor T1 (called "2(7)" with a gray line) to the middle T2 sensor (named "2(6)" that has an orange line) and the heat finally reaches the third sensor T3, a green line named "2(5)". T3 is at the end of the conducting aluminium fin on the warm side close to the shaft in the middle of the GREC. You can see the sensor layout and colours in this picture:
Heat Sensor Colouring


The Graph also shows an almost constant temperature in the cold conducting fin which is totally correct since its only contact is air with ambient temperature. (Remember the Revolving Shutter is parked with its work Generating Volume above one neutral "nil" fin.)

The graph shows that the air above the hot fin is heated and travels in the gap between the fins and the Revolving Shutter and heats up the two heat sensors (violette and brown lines) of the covered paired insulating "nil" fin that will measure the air temperature of the passing Work Generating Volume. The other insulating "nil" fin temperature sensors show ambient air temperature which is absolutely correct since it has the open Work Generating Volume filled with ambient air parked above its two heat sensors.

Conclusion:
- All the heat sensors in the thermistor chain works.
- The heat sensors in the conducting fins measures the temperature of the metal of the fin proving its heat transport.
- The thermistors in the neutral isolating "nil" fins measures the temperature of the air above the fins.

Note:
The the MCP3208 A/D circuits reads the analog pt500 termistors and delivers a digital value to the DynamicLink program. There are some very random fluctuations in the digital values. Minimising these fluctuations will save us a lot of work in analysing future results.