Design specification:
• Pressure sensor as an import substitute of thrust chamber pressure and other engines.
• Item description: MEMS based pressure sensing using AlN as the piezoelectric material.
• Sensing technology : Piezoelectric
• Pressure range : upto 10 MPa
• Sensitivity : 10 pC/ MPa
• Operating Temperature : 750 degC
• Resonant frequency : 6-10 MHz without water flow
• Weight : <= 50 gm

Introduction:

Dynamic pressure sensors in contrast to static pressure sensors measure pressure changes in liquids or gases generated due to blast, propulsion or explosion, where the temperature is normally high of the order of 700 deg C. Pressure sensing may be realized using piezo resistive, capacitive, fibre optic and Piezo electric principles[2]. Piezo resistive sensors have the drawback of temperature dependent resistance variation which leads to error in measurement at high temperatures. Capacitive sensors lack robustness and are prone to parasitic capacitive effects though they have better stability against thermal drift. Performance of fiber optic sensors is much dependent on packaging the optical components for high temperature operation with added cost on signal conditioning and processing. Piezo electric pressure sensors with their inherent advantage of direct transduction capability are drawing attention for high temperature applications with introduction of new materials like AlN[3]