Influence of Turbine Wheelspace Temperature on Measurements of Radial and Axial Displacements of Blade Tips
This paper presents the results of a simplified analysis of a differential measuring circuit with pulsed supply of the single-coil eddy current sensors connected to the circuit, with approximate differentiation of currents, and with an ADC at the output. The circuit is designed as part of automation systems for tests of gas turbine engines. Methods for eliminating the temperature influences on the sensors using the hardware and software of the measurement system are considered. Using a model of the measuring circuit, we determined the families of conversion functions (dependences of the code on the desired radial and axial displacements) for normal and nominal temperatures and then, from their difference, the families of functions of temperature influence on code changes, which characterize possible errors. Quantitative estimates of the maximum values of the influence functions were obtained which confirm the efficiency of the proposed methods.
Keywordsturbine complex-shaped blades single-coil eddy current sensor radial and axial displacements methods for eliminating the influence of temperature on the sensor
Unable to display preview. Download preview PDF.
- 1.S. Yu. Borovik, M. M. Kuteynikova, B. K. Raykov, et al., “Method for Measuring Radial and Axial Displacements of Complex-Shaped Blade Tips,” Avtometriya 51 (3), 104–112 (2015) [Optoelectron., Instrum. Data Process. 51 (3), 302–3092 (2015)].Google Scholar
- 2.Methods and Tools for Measuring Multidimensional Movements of Power Plant Components, Ed. by Yu. N. Sekisova and O. P. Skobelev (Samara Scientific Center, Samara, 2001) [in Russian].Google Scholar
- 3.V. G. Gerasimov, V. V. Klyuev, and V. E. Shaternikov, Methods and Devices of Electromagnetic Control (Spektrum, Moscow, 2010) [in Russian].Google Scholar
- 4.Eddy Current Testing at Level 2: Manual for the Syllabi Contained in IAEA-TECDOC-628. Rev. 2 Training Guidelines for Non Destructive Testing Techniques, Training Course Ser. No. 48 (IAEA, Vienna, Austria, 2011).Google Scholar
- 5.Eddy Current Displacement Transducer — High Temperature Specifications, Specifications Sheet, 1–5 (2013).Google Scholar
- 6.Y. Lai, Eddy Current Displacement Sensor with LTCC Technology, Dissertation zur Erlangung des Doktorgrades der Fakultät für Angewandte Wissenschaften der Albert-Ludwigs Universität Freiburg im Breisgau, 2005.Google Scholar
- 7.V. N. Belopukhov, S. Yu. Borovik, M. M. Kuteynikova, et al., “Measurement of Radial Clearances with Increased Sensitivity in the Extended Range of Axial Displacement of the Turbine Wheel,” Mekhatronika, Avtomatizatsiya, Upravlenie 18 (4), 174–184 (2017).Google Scholar
- 8.S. Yu. Borovik, M. M. Kuteynikova, B. K. Raykov, et al., “Measurement of Radial Clearances between the Turbine Stator and Complex-Shaped Blade Tips using Single-Coil Eddy Current Sensors,” Mekhatronika, Avtomatizatsiya, Upravlenie, No. 10, 38–46 (2013).Google Scholar
- 9.S. Yu. Borovik, M. M. Kuteynikova, Yu. N. Sekisov, and O. P. Skobelev, “Analysis of Temperature Influence on the Informative Parameters of Single-Coil Eddy Current Sensors,” Avtometriya 53 (4), 104–111 (2017) [Optoelectron., Instrum. Data Process. 53 (4), 395401 (2017)].Google Scholar
- 10.S. Yu. Borovik, M. M. Kuteynikova, Yu. N. Sekisov, and O. P. Skobelev, “Model of a Measuring Circuit with Time-Varying Equivalent Inductances of Single-Coil Eddy Current Sensors,” in Proc. XVI Intern. Conf. Complex Systems: Control and Modelling Problems (Samara Scientific Center, Samara, 2014), pp. 687–691.Google Scholar
- 11.M. M. Kuteynikova, Yu. N. Sekisov, and O. P. Skobelev, “Model of the Electromagnetic Interaction between the Sensitive Element of a Single-Coil Eddy Current Sensor with a Complex-Shaped Blade Tip,” in Proc. XVI Intern Conf. Complex Systems: Control and Modelling Problems (Samara Scientific Center, Samara, 2013), pp. 627–635.Google Scholar