Running an Experiment
1. Cut the desired length of thermocouple wires. For a K-Type
thermocouple use one red wire and one yellow wire.
2. Melt off one inch of sheathing from each wire using a lighter.
3. Twist the exposed wires together 3 or 4 twists.
4. Locate the green welding machine on the workbench. Clamp the exposed
wires into the clip at the end of the wand. Use scissors to trim the free end
of the twisted wires, making them the same length.
5. Using the 2.5 Amp setting on the welder, weld the wires together by
touching the free end of the wire to the contact on top of the welder and
pressing the red button labeled "weld".
6. Untwist the wires so that they meet at the bead.
Cellulose experiments
1. With the sample holder lying flat on the table, secure the cellulose samples between the
aluminum plates. The sample thickness can be increased by sandwiching multiple sheets
together in the holder.
2. Position the ignition wire so that it is touching the top of the fuel sample.
3. Attach the sample holder to the carriage of the
Flametracker assembly, and connect the ignition wires.
PMMA experiments
1. Line the rectangular cavity of the sample holder with silicate fiber insulation.
2. Insert the PMMA sample into the center of the cavity.
3. Pack insulation around each side of the sample, and secure it in place by
tightening the clamp.
4. Position the ignition wire so that it is resting against the top front corner of the fuel sample.
5. Attach the sample holder to the carriage and connect the
ignition wires.
1. Turn on the Flame Tracker P.C. ( The DeEx 486).
2. At the prompt type 'TRACK40'.
3. Press 1 for FLAME TRACKING
4. Enter P for a PMMA experiment or C for a cellulose (paper) experiment.
5. Enter the reference voltage in millivolts. This is the target voltage for the stationary
thermocouple in front of the flame. A value of 5 should be
entered for most experiments.
6. Enter the feedback gain coefficient K.
7. Enter the damping coefficient Td.
8. Enter the integral coefficient Ti.
9. Press enter to save the data in a file.
10. Enter the file name.
11. Enter the file directory.
12. Enter a brief description of the experiment. Record information such as room temperature
and relative humidity. Hit return twice when finished.
13. Load the fuel sample in the holder. Connect the ignition wire, and position it so that it is
touching the top front of the fuel sample.
14. Attach the fuel sample holder to the carriage.
15. Position the tracking thermocouple so that it is touching the surface of the fuel. Use the
toggle switch mounted on the side of the cage to move the sample holder up and down. Verify
that the sample is verticle by measuring the thermocouple distance at the top and bottom of the
fuel sample.
16. Use the toggle switch to position the thermocouple just below the top of the fuel sample.
17. Press S to start the experiment.
18. Two boxes will appear on the screen. The top one is plotting velocity vs. time. The bottom
one is thermocouple voltage vs. time. The experiment is successful when the voltage vs. time
plot is a strait line at the reference voltage. Adjustments of the coefficients Ti, Td and K can be
made during the experiment to improve the tracking performance. Ti, Td and K can be toggled
up and down using the keys {i,o}, {d,f}, and {k,l} respectively.
19. Press the space bar when the experiment is complete.
Using the FLAMEPROBE to measure the temperature field in a gas
1. Turn on the Flameprobe P.C. (The IBM AT).
2. At the prompt type probe40.
3. Type <1> for manual positioning.
4. Enter the velocity (mm/s).
5. Position the Flameprobe thermocouple using the joystick mounted on the side of the cage.
The velocity of the probe can be increased by pressing the button on the front of the joystick.
The velocity can be decreased by pressing the button on top of the joystick. The temperature
measuring thermocouple should be positioned so it is touching the surface of the fuel sample,
just above the tracking thermocouple. Press when finished.
6. Press <2> for Temperature Reading.
7. Enter the horizontal distance. This is the distance the probe will move perpendicular to
the surface of the fuel. A value between 5mm and 10mm is good for PMMA.
8. Enter the vertical distance. This is the distance the probe will move parallel to the
surface of the fuel. This value should be between 5mm and 25mm for PMMA.
9. Enter the number of points in the horizontal direction.
10. Enter the number of points in the vertical direction.
11. Enter the temperature range for convergence. If the difference between the maximum
and minimum temperature during the prescribed time segment is greater than this convergence
range, then the computer will continue taking data until the temperature range converges.
12. Enter the averaging time at each point. This is the time segment over which the
temperature must converge. It is the minimum amount of time that the probe will stay at one
point.
13. Enter the themocouple type.
14. Enter the channel of the Exp-16 board that the thermocouple is attached to.
15. Press Y to save data. Enter the file name the data wil be saved in. Enter the directory
the file will be placed.
16. Press Enter to start the data acquisition. Make sure that the flame tracker program is
tracking the flame properly before starting the Flameprobe. If
the thermocouple breaks during the experiment use
to abort.