2300K Gas Turbine Temperature Probe

Cambridge Aerothermal’s flagship technology (The Sonic Probe) is a new kind of thermometer which can be used to measure gas temperature in the extremely harsh conditions found in a gas turbine engine combustion chamber.

The technology has been developed in partnership with Mitsubishi Heavy Industries, for use in their combined cycle gas turbine engines.

The Sonic probe is capable of continuous gas temperature measurements well in excess of 2300K. The probe can operate in high pressure environments, and within high gas velocity streams. Several probe tests have been performed at 2300K, 20Bar total pressure, and Mach 0.4 gas stream velocity. A typical total temperature measurement uncertainty of ±1% is achieved.

Sonic probes can be developed/designed/supplied on request.

Machine Learning Aerodynamic Probes

At Cambridge Aerothermal we have been developing a pool of expertise around Machine Learning, and the benefits it can bring to measurement precision.

A series of Machine Learning aerodynamic probes (5-hole, 7-hole and 9-hole) have been developed in partnership with the Whittle laboratory at the University of Cambridge.

[Ref: GT2019-91428 Proceedings of ASME Turbo Expo 2019]

Benefiting from the extensive aerodynamic measurement experience at the Whittle lab, the new probe designs and data reduction algorithms are capable of increasing measurement resolution, reducing measurement uncertainty, and significantly increasing probe incidence tolerance when compared to probes with traditional calibration algorithms.

Machine learning aerodynamic probes can be supplied on request.

Sensor design, build & test – in one week!

A new angle insensitive total pressure sensor was developed, built, tested and iterated by Cambridge Aerothermal in under a week. The sensor was developed for use in a gas turbine combustion chamber, and has gone on to complete successful testing at engine conditons.

The speed at which we were able to develop this technology was enabled by our company culture and system of work. Design iterations could be created, manufactured and tested within as little as an hour, allowing the design to mature in a number of days.

Fast Response O2 Sensor

At Cambridge Aerothermal we have been developing fast response Temperature By Gas Analysis (TBGA) instrumentation. In combustion processes, an important parameter to determine flame temperature and pollutant formation is O2 concentration.

TBGA gas analysers are usually slow with response times greater than 30s. Cambridge Aerothermal’s O2 sensor has a response time as low as 20ms which allows for rapid traversing across a combustor, significantly shorter test times and measurement during transient operation.

Soft sensor and sensor fusion temperature measurement

At Cambridge Aerothermal, we have been developing machine learning and sensor fusion techniques to get measurement systems with even better accuracy and instruments with error detection and correction. Furthermore, our sensor fusion instruments can provide a high-fidelity correction of a sensor that is erroneous.

We use a single point sampling system where a sonic probe (Case Study 1) measures total gas temperature by (i) the Sonic Method, (ii) O2 TBGA and CO2 TBGA. For example, the uncertainty (3σ) for a specific measurement for the Sonic Method is ±1.8%, O2 TBGA is ±4% and CO2 TBGA is ±3%. By combining the result, shown in Figure 1, our Sensor Fusion method has an overall uncertainty of ±1.4% which is better than each instrument alone. Also, in Figure 2, the Sensor Fusion method can detect an erroneous instrument, in this case, CO2 TBGA. The Sensor Fusion uncertainty becomes ±1.6%, which is still better than each instrument alone as well as being able to estimate the CO2 TBGA providing a ‘virtual’ CO2 measurement.