How do sensors stay attached to gas turbine stationary and rotating parts?

In order to bond the wireless, high temperature PDC sensors on the blade metal surface, preliminary bonding study was initially conducted using proprietary high temperature adhesives to address the risk of implementing the new sensor system in the harsh turbine environment. The environment that our sensor will be operating at will be a high temperature, high pressure, corrosive environment. Considering all these factors, the ideal properties for a bonding material for our application are as follows:

– High temperature resistant

– High pressure resistant

– Corrosion/Oxidation resistant

– Identical Co-efficient of Thermal Expansion to Thermal Barrier Coatings & Blade Material

– Easy application & storage

– Optimal Cost.

Figure below shows a microscopical image of the bond-line interaction between the Inconel substrate and the PDC before and after being subjected to static high temperature furnace testing. It can be observed that there is no significant change to the bond-line after exposing it to high temperatures.

 

 

After bonding material feasibility was established in a static furnace test, the PDC sensor was exposed to the dynamic hot exhaust gases of a microturbine. Also, a  series of high temperature exhaust tests were conducted using a JetCat P200 RX microturbine to establish proof of concept for sensor functionality when exposed to an environment with constant thermal shock, dynamic pressures, high velocity & temperature gas flow. This type of environment is representative of the actual working environment that the sensor is going to be placed in for its ultimate application. The frequency response, magnitude of reflected signal was recorded along with temperature data from thermocouples for the duration of the tests.