Enhanced static-dynamic pressure transducer suitable for use in gas turbines and other compressor applications

Abstract

A filter assembly for use with a static-dynamic piezoresistive pressure transducer that measures low amplitude, dynamic pressure perturbations superimposed on top of a high static pressure through the implementation of a low-pass mechanical filter assembly is disclosed. The filter assembly may comprise a dual lumen reference tube and a removable filter subassembly further comprising a porous metal filter and narrow diameter tube. The transducer, which may be capable of operating at ultra-high temperatures and in harsh environments, may comprise of a static piezoresistive pressure sensor, which measures the large pressures on the order of 200 psi and greater, and an ultrasensitive, dynamic piezoresistive pressure sensor which may capture small, high frequency pressure oscillations on the order of a few psi or less. The filter assembly may transmit static pressure to the back of the dynamic pressure sensor to cancel out the static pressure present at the front of the sensor while keeping dynamic pressure from reaching the back of the sensor. In this manner, the filter assembly enables the transducer to accurately read dynamic pressure in the presence of high static pressure without rupturing the thin diaphragm of the dynamic pressure sensor.