A heat transfer sensor includes a support body, a first thermocouple probe, a second thermocouple probe, and a third thermocouple probe. Each thermocouple probe is mounted to the support body and includes a hollow cylinder, a thermocouple, and an insulator. The thermocouple is mounted to an interior of the associated hollow cylinder and is configured to generate a first voltage based on a temperature of the associated hollow cylinder. The insulator is mounted between the associated hollow cylinder and the top wall. The first hollow cylinder has an emissivity ≤0.25. The second hollow cylinder has an emissivity ≥0.75. The third thermocouple probe has an emissivity that is >0.25 and