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Engine photo 1
Engine photo 2
Sensor Specifications

High-Temperature Dynamic Pressure

Accurate, high response pressure measurement is required to adequately characterize transient gas path conditions in gas turbine test articles. Specific applications include operability, stall boundary definition, combustion dynamics, and quantifying blade passing forcing functions. High response pressure measurement necessitates that the sensor be mounted as close to the gas path as possible thus minimizing (ideally eliminating) response degradation resulting from installation pneumatic volume. A consequence of this mounting constraint is that the sensor will be exposed to gas path temperatures.

Current Sensor Needs

The table below outlines the general high temperature dynamic pressure transducer requirements for the near future, taking into account realistic expectations for technology development. The primary limiter for this type of device is currently temperature capability. In the very near term we would like to have available for purchase devices that can operate at up to 1100 degrees F. Within the next five years, on the order of 1500 degrees should be reasonably expected. And, the current long-term need is for sensors that can operate in excess of 2000 degrees F. For gas turbine engine validation and development minimum sensor life expectancies in the hundreds of hours range is acceptable and for production engines tens of thousands of hours is required. Currently piezoresistive transducers are favored over competing technologies because of their ability to measure both the absolute pressure level and the dynamic pressure variation with a single device. However, depending on capabilities, other technologies will be considered. Cooling of the sensors tends to add complication to the measurement and can be impractical. Varying operating temperature must not compromise measurement accuracy and influence on the sensor's pressure signal must be inherently negligible or compensated out. In general the sensors should be tolerant of contaminants such as water, fuel, dirt, sand, and bugs. Consideration should also be given to the ruggedness and temperature capability of the transducer's ancillary components, such as cabling, electronic modules, and connectors.

Range (psi)25 - 750
Excitation (VDC)5 - 10
Input Impedance (Ohms)350 - 2500
Full Scale Output (mV)100
Isolation From Case (Meda-Ohms)20
Output Impedance (Ohms)350 - 2500
Combined Uncertainties @ Ambient Temperature≤ 1% FS
Temp. Effect on Zero+/- 2%
Temp. Effect on Sensitivity0 to 2% FS
Natural Frequency≥ 100kHz
Acceleration Sensitivity≤ 0.001% FS/g
Diaphragm Operating temperature Range (deg. F)0 - 1400
Compensated Temp. Range (deg. F)0 - 1400
Lead Wite Operating Range (deg. F)0 - 1400
Diameter (in.)0.062 - 0.19
Length (in.)< 1.25
Temperature Compensationinternal
Protection Screenoptional

Strategic Advisory Board (SAB) Members Addressing This Need

Aerodyn Engineering, Inc.

Goodrich Sensor Systems

Prime Photonics

Sporian Microsystems, Inc