LEVEL OF AGREEMENT

MOST DISCUSSED PARAGRAPHS

P45 • Range 1The range, usually expressed as ”±_
4 0
P40 • Dead volume 1For non-flush-mounted transdu
4 0
P29 Piezoelectric pressure transducers offer man
3 0
P42 • Capacitance vs. temperature 1This may be g
2 0
P26 Transverse means that the charge is collecte
2 1
P37 Outline:This chapter should contain an overv
2 0
P91 Outline:Description of conditions within dif
1 0
P86 One way of mitigating the influence of pipe
1 0
P46 • Life, cyclingExpressed as ”__ full scale o
1 0
P43 The following performance characteristics, u
1 1
P4 Measuring dynamic pressures within the varyi
1 0
P41 • Capacitance 1The capacitance of the transd
1 0
P7 Outline:This chapter shall present currently
1 2
P36 Sensing MechanismAdvantagesDisadvantagesCapa
1 0
P28 There are different materials available that
1 1
P23 Piezoelectric transducers for dynamic pressu
1 0
P244 Dynamic Range – The ratio of specified maxim
1 0

LATEST COMMENTS

I think it makes sense to group this section with section 11, "Operating Conditions within Gas Turbines".
Good point, but customers also need to exchange components easily if needed. I do not know if whole measurement performance example needs to be in the datasheet. It can vary quite a lot. Maybe as optional point.
Would be interested in that sensor. To my knowledge it is up to 700°C with minor short term exceptions.
Several specification like frequency response, full-scale output for piezo electric sensors are additionally influenced by the charge amplifiers and cables. For the end customer the measuring chain performance may be of interest
Even when you decided to go with your sensor technology it is still challengine to find the right sensor for your needs as requirements for temperature, sensitivity, mounting space, reliability, robustness, calibraton intervalls, cross sensitvities, etc need to be considered.
The grounding concept should be shown including all parts of the measuring chain for example with a block diagram / electical schema
Information about the diaphragm are on one hand very sensitive and protected by the sensor manufacturer. On the other hand the acceleration sensitivity is specified in the datasheet.
Piezoelectric sensors have a long history in gas turbine monitoring and is well established. The longivity requirements are fullfilled. When talking about temperature capabilities it may make sence to distinguish long and short term capabilities.
Beside the mentioned crystal materials are several other piezo electric materials without pyroelectric effect and a stable high temperature performance available (e.g. PiezoStar)
We agree with Lukas that there are various design options and no standard design will be established.
Life, cycling: Instead of a quantified time period the requirement of a steady thermal condition could be considered
"Acceleration error 2" and "vibration error 1" could be considered in one specification?
In what medium the pressure measurement is taken, might be of interest to the sensor manufacturer. For example: Hydrogen, Ammoni, Biogas, Natural gas, diesel oil and combustion gases hereof.
Pressure transducer should be although as near as possible to the hot gas, to avoid wave distortion due to non-linear effect. I think it is better to develop in this direction, rather than to try to develop a sensor which should sustain > 700 °C. The sensor can be placed in the volume with cooling air. Such layout can also allow to install several sensors (for redundant), and it may also be possible to send calibration signal from outside
About Resonant frequency, it is better to describe if it is "mechanical" or "acoustical" resonant frequency..
I agree the comment of Lukas, and it is important. For a stationary signal (like combustor pulsation measurement) polarity is not important (so far all applied sensors are equipped with a same chain), but for a transient measurement, (like compressor surge, or rotating stall) it is important to note the polarity. When the sensor producer supply also an amplifier, the polarity of voltage signal should be noted.
Vibration isolation, if active acceleration compensation element is included or not
Diaphragm material, thickness and "weight" would be important to compare different sensor's sensitivities to acceleration
When dead volume is existing, (like CP10x, or Kulite Sensor with screen) it is better to specify an Helmholz Resonator Eigenfrequency at atmospheric temperature
maybe a rough cost/channel (incl. amplifier)
For piezoelectric transducer, the dynamic range is often limited by the charge amplifyer characteristics. Even with a very low amplification ratio, The output signal (voltage or current) is likely to clip at a lower pressure amplitude than the sensor itself could read.
0.97 bar
in my opinion a basic design characteristic and not supplemental
I would propose a table with applications including physical background, rough temperature, static and dynamic pressure ranges and maybe frequencies. This should be general enough not to disclose too many details.
As above, this is a very specific layout, more schematic cuts and description of longitudinal and transverse design would make more sense.
Maybe it is better to show two cuts of sensor layouts commonly used in turbines, with longitudinal and transverse layout.
more than 700°C
All the outlines can be deleted in the final version for better readability if necessary

MOST ACTIVE USERS

	Flavio Rosa	8	2

takashi.ando@ch.abb.com

7

0

Lukas Ladinig

6

54

Lukas Ließ SE

3

3

	Jonas D	2	0

Lukas_Ladinig

1

3

C_Jeunet

1

1