Novel heat flux sensor for SiC-SiC ceramic matrix composite engine components

• Published in: Sensors and actuators. A. Physical. Vol. 345; p. 113771
• Main Authors: Rivera, Kevin, Gregory, Otto J.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.10.2022; Elsevier BV
• Subjects: Calibration factor; Ceramic matrix composite; Ceramic matrix composites; Ceramics; Composite materials; Engine components; Gas turbine engines; Heat flux; Heat flux sensor; Heat transfer; High temperature; Silicon carbide; Thermocouples; Thermoelectric power; Thermoelectricity; Thin films; Ceramic matrix composite; Calibration factor; Silicon carbide; Heat flux sensor; Thermoelectric power
• ISSN: 0924-4247; 1873-3069
• DOI: 10.1016/j.sna.2022.113771

Silicon carbide-silicon carbide ceramic matrix composites (SiC-SiC CMC’s) are being used in gas turbine engine hot sections due to their refractory nature and excellent toughness at high temperatures. A novel heat flux sensor was developed for SiC-SiC CMC based engine components, which can survive temperatures up to 550 °C. The heat flux sensor consists of platinum thin films that forms a thermocouple junction with the SiC-SiC CMC which utilizes the bulk thermoelectric properties of the SiC-SiC CMC for its operation. This novel Pt:SiC-SiC CMC heat flux sensor generates a thermoelectric voltage that is directly proportional to the temperature gradient along the through thickness direction of the CMC component onto which it was deposited and has a calibration factor of 0.0266 µV/(W/m2). Fabrication details, experimental results and implementation challenges are discussed. [Display omitted] •A Pt:SiC ceramic matrix composite sensor that measures heat-flux was developed.•The calibration factor of the sensor was linear and 0.0266μV/(W/m2).•Upon repeated thermal cycling, the output of the sensor drifted by only 15μV.•Thermal conductivity is 0.323Wm−1K−1 to 1.054Wm−1K−1 with a mullite coating.•Thermal conductivity is 0.496Wm−1K−1 to 1.444Wm−1K−1 without a mullite coating.