Jet Engine Heat Transfer Telemetry

The project

The challenge was to build a sufficiently high density of telemetry channels into the shaft of a jet engine so that a series of tests could be run on a jet engine test rig, without having to spend months stripping down the engine, repositioning the sensors, and rebuilding the engine between test runs. This also meant that the system needed to be able to cope with different sensor types to measure heat transfer, temperature and pressure.

The electronics need to gather a huge amount of data within a short time of the triggering event, and then feed the results out.

Measurement accuracy close to thermal noise limit Bandwidth up to 1 MHz >100 channels Configurable measurement circuitry to match to sensors Rotate at up to 10,000 rpm

Novel measurement circuitry to balance measurement accuracy, power dissipation, configurability and sample rate Careful circuit layout to achieve required density, component placement to manage heat dissipation and G forces Mechanical support plates to achieve G force survivability and thermal dissipation

About our client

Osney Thermo-Fluids Laboratory , part of University of Oxford's Department of Engineering Science, is located in a brand new facility to the west of the city called the Southwell Building. The new laboratory was opened by the Vice Chancellor in 2010 as part of the University's strategic investment in the nation's science base. The lab houses some of the most sophisticated turbine and high speed flow facilities in the UK, and the research group includes internationally recognised experts in CFD, flow and heat transfer experiments and instrumentation.

In their words...

"As the designer of many of Oxford’s earlier heat transfer measurement systems, I am impressed with the performance of ASH's new design, in terms of bandwidth, noise performance and channel density.

This was an ambitious project, integrating both digital and analogue circuitry, and which needed to meet complex requirements, including spinning at 10,000 rpm, and operating in a vacuum. The ASH system is a significant step forwards in heat transfer instrumentation."

Martin Oldfield, Emeritus Professor of Engineering Science, University of Oxford