Infrared Thermopile Temperature Measurement Technique in Microwave Heating Systems

Temperature measurement in microwave systems is essential for thermally driven processes, namely, catalytic reactions and ceramic sintering. although, the application of direct thermometry methods, namely, thermocouples, have been commonly articulated in the avail- able literature, however, contacted temperature measurement mech- anisms have aroused concerns associated with the disruption of the electromagnetic field and local distortion of the field pattern leading to unprecedented measurement uncertainties. consequently, the appli- cation of optical measurement methods has been advocated to dimin- ish the associated concerns. however, due to the economic constraints and measurement range restrictions, the application of optical mea- surement systems, namely, pyrometers and optical fibers, has been deferred. in this study, an infrared thermopile, a precise and feasible temperature measurement system has been developed and calibrated to perform in microwave irradiation. furthermore, the accuracy of the developed temperature system has been compared with the thermom- etry technique. it was concluded that thermopile stipulates unrivaled precision, succeeding a profound calibration procedure. it was further demonstrated that the thermopile is capable of the temperature mea- surement of the dielectric surfaces, exclusively, while the grounded thermocouple monitored the bulk temperature, a proportion of the gas phase and the solid phase temperature values. consequently, the application of a thermopile coupled with a thermometry measure- ment method has been proposed to monitor the temperature of the dielectric catalyst active sites in gas-solid catalytic microwave-heated reactions.