Particle ingestion in gas turbine applications can be detrimental to performance and pose significant safety concerns. Areas of high sand concentration are hazardous to aircraft, requiring precautions like routine inspections and maintenance. The engine failure modes are dependent on particle composition, concentration, and size. Particles containing certain minerals tend to melt and stick to turbine blades, which is known as glazing. Alternatively, particles may erode blades from repeated collisions, or they may fill cooling passage holes. Therefore, it is necessary to develop systems that identify these parameters as particles are ingested. This thesis introduces three separate systems responsible for collecting sand concentration, size distribution, and material composition of sand. A particle visualization technique (ParVis), developed at Virginia Tech, was used to validate two sensors developed by commercial partners. One sensor measures particle size and velocity with a method similar to Laser Doppler Velocimetry (LDV). The second sensor measures particle composition with X-Ray Fluorescence (XRF) by physically sampling particles in a flow. There has been little research on applying XRF to moving particles, so experimental data were collected to demonstrate the effectiveness of the sensor. Detection comparisons between two particle types showed promising outcomes for the XRF. Meanwhile, the ParVis technique was iterated to overcome previous limitations and implemented into the testing process to provide particle concentration measurements. Particularly, improvements led to increased accuracy and reliability of the method such as reducing variance in concentration approximations. / Master of Science / Aircraft are constantly ingesting particles into their engines. Those operating in dusty environments are at higher risks of engine failure because more particles are ingested, which cause damage in several ways. As engine manufacturers push the turbine operating temperatures higher for efficiency and emissions, sand particles reach melting temperatures and stick to turbine blades, which results in overheating. Because of the potential risks to life, sand ingestion research continues to provide solutions for improving aircraft safety.
This study explores the capabilities of new sensors to quantify characteristics of ingested particles, including the concentration, size distribution, and material composition of sand. An illumination technique for measuring sand concentration from particle imaging was developed at Virginia Tech. The technique was iterated to overcome previous limitations and improve its reliability during this study. It provides a more accurate depiction of the testing conditions that can be used to diagnose and calibrate sensors. In this case, two sensors issued by Creare were tested, one of which measures size and particle velocity, while the other measures sand composition. The first sensor relies on non-intrusive optical measurements and can be mounted directly to an engine inlet. The second sensor collects particles from the inlet flow and applies X-Ray Fluorescence (XRF) to the moving particles. There has been little research on applying XRF to a flow of particles, so experimental data were critical to demonstrate the effectiveness of the sensor. technique was iterated to overcome previous limitations and implemented into the testing process to provide particle concentration measurements.
| Identifer | oai:union.ndltd.org:VTETD/oai:vtechworks.lib.vt.edu:10919/119399 |
| Date | 11 June 2024 |
| Creators | Rentsch, Nicholas Russell |
| Contributors | Mechanical Engineering, Lowe, K. Todd, Ng, Wing Fai, Son, Chang Min |
| Publisher | Virginia Tech |
| Source Sets | Virginia Tech Theses and Dissertation |
| Language | English |
| Detected Language | English |
| Type | Thesis |
| Format | ETD, application/pdf, application/pdf |
| Rights | In Copyright, http://rightsstatements.org/vocab/InC/1.0/ |
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