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Thermocouple measurement- Static or total temperature?
Thermocouple measurement- Static or total temperature?

Hi,

I would like to know if the exhaust temperature measurement of a gas turbine is the total temperature or a static temperature.

1 out of 1 members thought this post was helpful...

The exhaust temperature measurement on a GE gas turbine is total temperature. (The thermocouple probes are in the exhaust gas stream, which will give you total temperature.)

What's a "total temperature"?
What's a "static temperature"?

>What's a "total temperature"?
>What's a "static temperature"?

well there are several

1. static temperature is the temperature measured with the sensor traveling at the same velocity as the gas. In other word the temperature with no velocity effects.

2. stagnation temperature is the theoretical reservoir temperature of the gas stream you are measuring. It is approximately measured by a thermal probe at rest, although such a measurement are also affected by recovery effects.

3. Total temperature includes the static temperature and dynamic component related to the velocity of the gas (kinetic energy). This is approximately measured in practice, though recovery effects are also important.

As long as you are at subsonic conditions Mach<0.3, static and total are more or less the same if you've a properly installed measurement and the system is properly calibrated.