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2000
Week 36
Week 37
Week 38
Week 39
Week 40
Week 41
Week 42
Week 43
Week 44
Week 45
Week 46
Week 47
Week 48
Week 49
Week 50
2001
Week 2
Week 3
Week 4
Week 5
Week 6
Week 7
Week 8
Week 9
Week 10
Week 11
Week 12
Week 13
Weeks 14-20

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Monday: With the regulator available, we were ready to start working on the prototype set-up. Work went smoothly. Using whatever materials we could find, we made a very crude workplace in the room next to our own. It was empty, as it was waiting for paint and a new floor. This location was far from ideal, but the best that we could get.

The crucial part was making the control system function as intended. It turned out that installation was logic, and that the complete system worked in the first try. We installed the two side panels and the two front panels.

We used whatever materials we could find for the set-up, which reduced aesthetics but increased construction speed.

Tuesday: We installed the data logger, and started arranging thermocouples. The control system work by varying the time that the power to the foil is on during a 45 second-period. This causes the surface temperature to oscillate somewhat. We wanted to quantify these oscillations.

Wednesday: Had the system running all day and collected data at various set point temperatures. Observed that the time to reach equilibrium after a 10 degree-change of set point was around 20 minutes.

The system still ran as supposed. Spent the afternoon reading statistics.

Gunnar gave us the specifications of a foil (Tehlco) at a quarter of the price of the carawarm foil. We ordered a sample of the Tehlco foil.

Thursday: Had the statistics lecture in the morning. Spent the afternoon preparing a meeting with Geo and Fanger. We were to present whatever findings and results we had at the moment. Unfortunately it turned out that Fanger would not be able to come. We decided to have the meeting nonetheless.

Visited the climate chamber at the Department of Energy and Buildings. It turned out to be a basement room, which happened to be at a fairly constant temperature of 18.5° C. There had been a cooling system, but it did not work anymore due to a Freon leak. Installing the heating foils and other equipment would cause the room air temperature to rise; it was obvious that we could not use the room. Instead we decided to continue using the – so far – unused office next to our own. By installing a fan to supply outdoor air to the room, we should be able to decrease the temperature towards the desired temperature of 16-18° C.

Friday: Had breakfast with the department; Geo offered Gammel Dansk to celebrate his birthday.

Had a meeting with Jørn, Geo and Richard de Dear. Presented the project, and received valuable feedback.

Installed the Tehlco foil, which functioned as expected. The weather was warm for early October, which kept the cubicle air temperature above 20° C. In the afternoon the fuse of the transformer that supplied the foils kept blowing. We were unable to find the reason for this. The day ended early.

Formulas for the function of temperature and resistance for the thermal sensors used:

Anne’s correlation: -53.2 log(R) + 226.49

Gunnar’s correlation: 399.883 – 71.5580 ln(R) + 4.027 (ln(R))² – 0.1064 (ln(R))³

Neither correlation was found to be sufficiently exact at 0° C or 100° C.