Calibration and Test Run Plan

8 Nov 2012

Overview

We need to fully understand and be able to document how the test cell responds to heat being generated by the two wires inside it.  Once we load the active “Celani wire” with hydrogen inside the cell, we do not want to remove the wire from the cell.  That means any conditions we plan to do the initial replication at, or any that we may have as a backup set of conditions, need to be fully explored ahead of time.

This procedure is intended to be for the initial replication ONLY.  What do we need to do to prove to ourselves that this works.  What range of gases and pressures will we want to be prepared to try for the initial runs?

Variables:

Glass

Borosilicate or Quartz - this needs to be determined before we start any other step.  However, we may choose to make up new test cells and run in parallel.

Because we plan on replicating Celani’s apparatus exactly, we want to use the same glass type and grade in order to not modify the conditions favorable that created excess heat for him.

We have to start with a borosilicate glass that absorbs up to 3 µm wavelength infrared light generated by the active wire. Then, after we have solid results and solid convictions, we can swap the glass tubes for quartz to help designing the next generation of cell.

Borosilicate tube validated by Celani. Nicolas handled amazingly the calculation and we are able now to anticipate how do the glass design has to be managed for further design.

Wire

Key considerations for the wire include the diameter, the similarity to Celani’s apparatus, the emissivity, and the resistivity.  Potential reactivity is another consideration.

The possibilities for wires include

We will use exactly the same wire that Celani uses (55%Cu, 44%Ni, 1%Mn) but without the original coating. Celani uses a 2 kW heat-gun to uncoat his wires. We have to do the same. Celani’s constantan wire is also composed of 1% of Mn. We have to comply with this if we want to prove replication.

The Isotan 44 we have at HUG is bare - no coating.

Gas

Celani uses He to calibrate his cell. We have to give these plot for further calibration by independent parties. As mentioned by Rick, we should do calibration during a longer period of time than the duration of the experiment.

Ar is used in mixture with H2 to artificially decrease thermal conductivity inside the cell. Doing Ar calibration would be a plus but is not mandatory.

Same for pure H2. He used this at the beginning but it didn’t worked out because of insufficient wire temperature.

Same for N2. The idea was that H2 is molecular. N2 is molecular and neutral.

25%Ar 75%H2 is the recommended gas mixture by Celani. He said this is the gas they used for brand new wires (they increased Ar later on). This has to be done. Going to 5 bar with this mixture at full regime can be done injecting 3.5 bar doing the following: Inject 0.9 bar of Ar (25% times 3.5 = 0.875) into the cell, then top it up to 3.5 bar with H2 (75% times 3.5 = 2.625).

Pressure

Celani recommended a max pressure around 5 bar range to minimize the risk of explosion.

The starting pressure at room temperature is what we will specify.  As the temperature rises, so does the pressure in the cell, which can be modeled by the ideal gas law.

Using an inert gas in a well sealed test cell, we should be able to determine the average cell temperature from the gas pressure.

Set the right pressure will be done by the following. Using a vacuum pump we can pull the ambient air out of the tube. A classic pump should be able to pull up to 1.3E-5 bar (1E-2 torr). Celani says it’s fine. Then we inject the gas very slowly, especially at the beginning using the needle valve. It is important to pay attention to the arrow on the swagelok quarter turn valve and needle valve.

Pressure Ratio

Starting = ~300K

Working Temp = 300C = ~600k  => Allow for doubling of pressure and staying under 7 bar so we start with max of 3.5 bar

Max Temp = 400C => should be OK

Calibration Cycles

Each calibration cycle will be done using the same automated script.  We should do additional tests to determine the difference between a stepped vs continuous rise calibration. and settle on the resulting calibration script.

At the moment we have a 16 point stepping calibration controlled by voltage instead of power.  Each step is held for 45 minutes.  The power is returned to zero at the end and allowed to cool for 45 minutes before the script ends.  The total time for a cycle is almost 13 hours.

This script is run for just heating with the wire in the place of the active wire on Channel 2, which is the Isotan 44 wire.  

The active wire should be installed on the Red Channel (Channel 2)

Results for each Calibration run:

Control Calibration Table

#

Wire

Gas

Starting Pressure

American Cell Data

(using Quartz so far - 11/5//12)

Euro Cell Data

1

Isotan 44/NiCr

He

3.5 Bar

(50.7 psi)

Cal1_USA.csv (3.5 mb)

Cal1_USA.xls (29 mb)

2

Isotan 44/NiCr

He

2 bar

Cal2_USA.csv (3.6 mb)

Cal2_USA.xls (31.6 mb)

3

Isotan 44/NiCr

He

.3 Bar

Cal3_USA.csv (3.7 mb)

Cal3_USA.xls (33 mb)

4.a

Isotan 44/NiCr

Heat w/Isotan

75%H

25%Ar

3.5 Bar

Cal4a_USA.csv (3.8 mb)

Cal4a_USA.xls (25 mb)

4.b

Heat w/ NiCr

75%H

25%Ar

3.5 Bar

Cal4b_USA.csv (3.6 mb)

Cal4b_USA.xls (37 mb)

4.c

Heat w/Isotan

75%H

25%Ar

3.5 Bar

Cal4c_USA.csv (3.6 mb)

Cal4c_USA.xls (36.5 mb)

4.d

Heat w/ Isotan

75%H

25%Ar

3.5 Bar

Cal4d_USA.csv (3.6 mb)

Cal4d_USA.xls (31 mb)

5

Isotan 44/NiCr

75%H

25%Ar

2 Bar

Cal5_USA.csv (3.5 mb)

Cal5_USA.xls (20 mb)

6

Isotan 44/NiCr

75%H

25%Ar

.5 Bar

Cal6_USA.csv (3.5 mb)

Cal6_USA.xls (10.7 mb)

7

Isotan 44/NiCr

H

3.5 Bar

Cal7_USA.csv (3.6 mb)

Cal7_USA.xls (11 mb)

8

Isotan 44/NiCr

H

2 Bar

Cal8_USA.csv (3.3 mb)

Cal8_USA.xls (10.2 mb)

9

Isotan 44/NiCr

H

.5 Bar

Cal9_USA.csv (3.5 mb)

Cal9_USA.xls (10.6 mb)

 

Final Calibration Write Up 

*Note - Celani mentioned that we may expect to see a few percent of excess energy from the untreated Isotan wire in Hydrogen.  We should be able to test for that from calibrations done to date.

Active Wire Calibration Table

Wire

Gas

Pressure

American Cell Data

Euro Cell Data

Celani/NiCr

He

3.5 Bar

RunHe1_USA_RawData.csv (2.5 mb)

RunHe1_USA.xls (7.4 mb)

Celani/NiCr

He

.5 bar

11/9 PM

Final write up and analysis before loading with Hydrogen and Celani Wire

Calibration Outputs

Test Runs

Weigh Celani Wire

Load Celani Wire onto Reactor

Loading by heating with NiCr wires at 250 to 300C and 5 to 6 bar at H/Ar 75%/25% for days.

If resistance of Celani wire changes, assume it is loading and continue loading phase till resistance stops changing.

Change to heating Celani wire with current.

If excess heat appears in a measurable amount, hold current conditions and party.  Then commission new cells for other experiments.

Otherwise, drop the pressure to .5 Bar of pure H2 (to match calibration curve) and watch for excess heat.

If no excess heat, yet, keep altering conditions to match other calibration curves in order to work from a good benchmark.

Phase

Wire

Gas

Pressure

American Cell Data

Euro Cell Data

Loading

Celani/NiCr

Heat W/ NiCr

H

5 Bar at 250C

Link to Data, XLS,

Start 11/9

Running

Heat w/ Celani wire

75%H

25%Ar

3.5 Bar & 270C