Study On Temperature Characteristic Simulation Based On High Temperature Blackbody Cavity Sensor

In the fields of chemical material industry, spaceflight, and metallurgy industry, it is very important to measure the transient temperature of strong immersed-erode medium. At present, thermocouple and optical fiber pyrometer are in common use. The thermocouple has some disadvantages, such as short life, rapid consumed, small temperature range; fiber pyrometer is not contact with the measured temperature medium directly, influenced by external environmental factors easily, so has low sensitivity.In this paper, a high temperature blackbody cavity sensor is issued, which can achieve high transient temperature measuring under the evil environment. In high temperature blackbody cavity sensor, advantages belong to contact and non-contact temperature measurement are combined, study on temperature characteristic based on high temperature blackbody cavity sensor, temperature characteristic include the static characteristic and the dynamic characteristic.Study on the static characteristic based on high temperature blackbody cavity sensor. This paper established the mathematic model of blackbody cavity sensor integrated emissivity based on integral equation theory, calculate the cavity integrated emissivity. Then introduce the concept of the half-angle factor and calculate the half-angle factor; the difform blackbody cavity sensor model is established by the finite element method, and the blackbody cavity emissivity is calculated. The factors that influence the cavity emissivity, such as the radius of detector surface, the axis length of cavity, the material emissivity, the distance between the aperture and the detector are analyzed. The optimum high temperature blackbody cavity sensor is designed by comparing the cavity emissivity of blackbody cavity of different shapes.Study on the dynamic characteristic based on high temperature blackbody cavity sensor. Based on the finite element thermal analysis module, the dynamic characteristic of high temperature blackbody cavity sensor is simulated. The transient temperature change is analyzed based on the cylindrical blackbody cavity sensor. The factors that influence the high transient temperature, such as insertion depth, inner and outer structure, preheating temperature of sensors, thermal parameters, boundary conditions and other factors are analyzed, then the optimum high transient temperature blackbody cavity sensor is designed.