Session: 05-04: Thermal Measurements

Paper Number: 152930

Projection Method for Irreversible Thermochromic Paint Post-Processing Using Endoscope Images on Turbine Blade Surfaces 

In order to achieve higher efficiencies, turbomachinery is increasingly being pushed to its performance limits. This results in high thermal loads for the turbomachinery components. Even small changes in temperature have an impact on the service life of the highly stressed components. For this reason, precise measurement of temperature values is crucial for the design process of gas turbines. Irreversible thermochromic paints are a suitable and proven measurement method for this purpose. The analysis of thermochromic paints is currently a manual task for experts and therefore a cost-intensive process. For this reason, the semi-automation of thermochromic paint post-processing using colored turbine blade surfaces would be an important milestone. If it is feasible to measure and evaluate the projected thermochromic paint data, the test engine does not require disassembly for analysis, and further testing can be performed afterward.

In this paper, a process chain for projecting endoscope images onto a geometric surface of a turbine blade is set up. Firstly, the alignment method is presented, which is impaired by inhomogeneous illumination, no vertical recording angles and no coded reference points. The color information is then transferred to the geometry surface and the result is presented. The integration of thermochromic paint information enables a more accurate and efficient assessment of the service life and performance characteristics of the engines as well as the possibility of transfer to the design systems. Finally, an approach that identifies temperature gradients on the 3D surface is introduced.

Presenting Author: Benjamin Endrulat Technische Universität Dresden

Presenting Author Biography: 03/2023 – present Technische Universität Dresden, Research Associate at the Chair of Turbomachinery and Flight Propulsion, Dresden, Germany
07/2017 – 03/2023 German Armed Forces, Liaison Officer for Civil-Military-Cooperation, Dresden, Germany
10/2012 – 04/2021 Technische Universität Dresden, German Diploma (MSc) Aerospace Engineering, Dresden, Germany
07/2011 – 06/2012 German Armed Forces, Naval Specialised Forces, Eckernförde, Germany
07/2010 – 06/2011 German Armed Forces, Navy Officer School, Flensburg, Germany

Authors:

Benjamin Endrulat Technische Universität Dresden
Md Tarekul Islam Technische Universität Dresden
Matthias Voigt Technische Universität Dresden
Robert Kossakowski Rolls-Royce
Ronald Mailach Technische Universität Dresden
Stefan Gier Rolls-Royce