Integrated Smart Bolt Sensor for Synchronous Temperature and Heat Flux Detection without Active Cooling Structure

Measurement of heat flux and temperature is of high importance in the heat conduction process. Current heat flux sensors can hardly meet the requirements of compact size and fast response. In this study, we formulated a smart bolt sensor that integrates temperature and heat flux to satisfy thermal measuring. Compared to the Gardon gauge, this sensor is packaged in M6 bolt, which is small size and easy installation. The corresponding integrated full-scale error is about 4.57%, and the output consistency error is 2.67% within 0∼70 kW/m². This sensor requires no active cooling when used at high temperatures. Temperature and heat flux parameters can be detected synchronously, and the time constants of a temperature and heat flux were 0.37 ms and 1.42 ms, respectively. The sensor has potential applications in industrial scenes, such as square billet molds and aircraft engine compressors.