Annular cooler temperature measurement method and device based on data fusion

The device comprises an acoustic temperature measurement system, an air pressure temperature measurement system, a thermocouple temperature measurement system and an infrared temperature measurement system which are arranged in a box body, and the acoustic temperature measurement system and the air pressure temperature measurement system are arranged on the inner side of a front plate, making contact with a measured object, of the box body. The box body is filled with a high-temperature fire-resistant filler and a heat-insulating substance; the four measurement systems respectively obtain temperature measurement data of a front plate of the box body, time difference between generation and reception of sound waves in the first cavity and internal air pressure of the second cavity. Temperature measurement data of the first cavity, the second cavity and the front plate of the box body serve as the temperature of a measured object, data fusion is conducted on the temperature measurement data through a computer, a