Vibration wave downhole communication technique

Passive Downhole Pressure Sensor Based on Surface Acoustic Wave Technology

A passive surface acoustic wave (SAW) pressure sensor was developed for real-time pressure monitoring in downhole application. The passive pressure sensor consists of a SAW resonator, which is attached to a circular metal diaphragm used as a pressure transducer. While the membrane deflects as a function of pressure applied, the frequency response changes due to the variation of the SAW propagat...

Characterization of EM downhole-to-surface communication links

A downhole-to-surface communication channel consisting of a long vertical cylinder (the stem) and an isolated downhole in-line cylinder (the electrode) embedded in a homogeneous earth is considered in this work. A signal voltage is applied between the electrode and stem, and the received voltage is picked up at the surface between the stem and a ground point or between two ground points. The an...

An automated damage identification technique based on vibration and wave propagation data.

This paper is concerned with the detection and characterization of hidden defects in advanced structures before they grow to a critical size. A novel method is developed using a combination of vibration and wave propagation data to determine the location and degree of damage in structural components requiring minimal operator intervention. The structural component is to be instrumented with an ...

Long-wave Marangoni instability with vibration

Surface Acoustic Wave (SAW) Vibration Sensors

In the paper a feasibility study on the use of surface acoustic wave (SAW) vibration sensors for electronic warning systems is presented. The system is assembled from concatenated SAW vibration sensors based on a SAW delay line manufactured on a surface of a piezoelectric plate. Vibrations of the plate are transformed into electric signals that allow identification of the sensor and localizatio...