SBIR-STTR Award

Measurements of combustion and gas dynamic properties inside gas turbine engines and augmentors are needed to aid in engine development, performance testing and evaluation, and for verification and validation of combustion modeling codes. Advanced instrumentation and flow-field diagnostics that combine the advantages of both intrusive and non-intrusive measurement systems are needed measure the transient gas chemical species characteristics and thermodynamic behavior in the combustion environments. Bodkin Design & Engineering (BDE) proposes to demonstrate a multi-modal sensor system with capability to measure multiple species concentrations (including free radical species such as OH, CH and NH), local fuel/air ratios, heat release, and fuel/air mix temperature inside a gas turbine engine or augmentor. The system will use fast, compact spectral measurement instruments operating simultaneously at both ultraviolet (UV/vis) and mid-wave infrared (MWIR) wavelengths. Additionally, the system will be capable of tunable diode laser absorption spectroscopy at both UV/vis and MWIR wavelengths. Measurements will be made using small, unobtrusive light pipes to observe the engine’s interior. This light pipe as well as the spectrometers can be configured either as point sensors or imaging sensors.

Benefit:
Passive sensors capable of measuring temperature and species concentrations of hot, reacting gas mixtures may be useful for development of commercial jet and turbine engine control systems for improved fuel efficiency and improved pollution control. Sensors of this type may also be useful as process control sensors and feedback controls for industrial processes ranging from metal and glass processing to pyrolytic ceramic coating to semiconductor fabrication as well as plastics and composites fabrication.

Keywords:
Gas Turbine Engine, Augmentor, Combustion, Optical Sensor, Flow-Field Diagnostics, Species Concentration Measurement

Measurements of combustion and gas dynamic properties inside gas turbine engines and augmentors are needed to aid in engine development, performance testing and evaluation, and for verification and validation of combustion modeling codes. Flame emission spectra in the ultraviolet and visible portions of the spectrum can be used to determine species concentrations, fuel-air ratio, and instantaneous heat release in liquid fueled gas turbine combustors. In Phase I, Bodkin Design & Engineering demonstrated snapshot hyperspectral imaging of hydrocarbon flames simultaneously recording spatial and spectral data. In Phase II, we will design a custom multi-modal sensor system that will measure multiple species concentrations (including free radical species such as OH*, CH* and C2*), local fuel/air ratios, heat release, and fuel/air mix temperature inside a gas turbine engine or augmentor. The system will use fast, compact spectral imagers operating simultaneously at both ultraviolet (UV/vis) and short-wave infrared (SWIR) wavelengths and will record hyperspectral images at frame rates as high as 2000 Hz. The completed system will be demonstrated on the J85 engine test stand at UTSI.

Benefit:
Combustion diagnostics has been an important area of research for half a century. Key improvements have led to more fuel efficient and less polluting engines of all types including aircraft and automotive engines, industrial furnaces, and power generating turbines. The system to be developed in this project will directly benefit the Air Force in its development of better jet engines since it will be an important tool for imaging fast, dynamic instabilities in combustion zones while simultaneously providing important chemometric and thermometric data.

Keywords:
Combustion, Augmentor, Spectroscopy, Species Concentration, Heat Release, Equivalence Ratio