DEVELOPMENT AND EVALUATION OF ADDITIVELY MANUFACTURED SENSORS FOR COMBUSTOR SURFACE TEMPERATURE, HEAT FLUX AND STRAIN MEASUREMENTS

System components with embedded sensors help obtain real-time system performance feedback and in situ monitoring during operation. This paper describes the development and assessment of embedded sensors fabricated employing a Direct Wire (DW) deposition process, which enables their integration directly onto the components being tested. Three separate combustor panels were additively manufactured using the Direct Metal Laser Sintering (DMLS) technique with 1) thermocouples, 2) heat flux gages, and 3) strain gages embedded on the cold side of combustor panels. These surface contact sensors are a few millimeters wide and are within 50 mu m thick and thus, have minimal effect on the reacting flow field of a combustor. They were first characterized in a controlled environment (oven and strain beam tests) and then tested in a single nozzle liquid spray reacting combustor simulating realistic aircraft conditions operated at elevated pressures of up to 4 bar and inlet temperatures starting at 410 K. These sensors survived the harsh operating environment involving high-temperature settings for an extended period and cyclic thermal loading and exhibited repeatable and reliable readings. This paper serves as a demonstration of these additively embedded sensors and provides data from the combustion test rig to show repeatability and transient response characteristics. This development is useful for R&D purposes of current-gen energy, automotive, and aerospace systems and in the development of more efficient and smarter next-gen combustion systems.