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| Flue Gas Analysis System | Theory of Operation 2 | |
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The temperature of the active bead will be influenced by other factors such as initial gas temperature, gas thermal conductivity, flow rates and the temperature of its housing. The reference bead, having similar electrical and thermal properties and being heated by the same current, but lacking the catalytic material will be similarly affected by these extraneous factors but not significantly affected by oxidation of the combustible gas.
These two beads are placed in close proximity. to one another so that they are affected by the same environmental factors. Thus, the differences between the changes in resistance of the two coils is directly related to the concentration of combustible gases.
TELEDYNE BROWN ENGINEERING |
Analytical Instruments
