Technical study of fast-response coil-type coaxial surface junction thermocouple

This study demonstrated the technical feasibility of the manufacturing process for a fast-response, small-sized coil-type coaxial surface-junction thermocouple. The performance of the coil-type coaxial surface-junction thermocouple was thoroughly assessed in a highspeed environment using a shock tunnel, operating at a nominal freestream Mach number of 6. To evaluate its efficacy, the measured surface heat flux data from the coil-type coaxial thermocouple were compared with results obtained from conventional coaxial surface-junction thermocouples, as well as theoretical predictions. Based on the experimental data, it is evident that the proposed coil-type coaxial surface-junction thermocouple is a viable option for use in a shock tunnel environment, exhibiting performance levels that are comparable to those of conventional coaxial surface-junction thermocouples. Moreover, when compared to conventional thermocouples, the proposed coil-type coaxial surface-junction thermocouple offers the potential to manufacture smaller-sized sensors using a cost-effective and straightforward process, owing to its simplified design and manufacturing method.