Theoretical aspects of the integration of thermography and pyrometry methods

Both thermovision and pyrometric measuring are widely used for the control of industrial process thermo modes, the technical service and diagnostics of equipment as well as the works on security and safety provision. The objective of thermovision measuring is the visualization and research of an object thermo field on the basis of temperature gradient identification at defined temperature sensitivity. The main purpose of pyrometric measuring is the identification of temperature values in certain object points with certain accuracy. Nowadays, it is expediently to solve the complex task based on both methods advantages’ unification in many technological processes: identification of object thermo field point temperature values with the needed accuracy. For this purpose it is necessary to integrate the methods of thermography and pyrometry on the basis of usage of these methods’ advantages as well as common disadvantages’ correction. Both thermovision and pyrometric measuring are tightly connected between themselves. When different tasks are available, they are based on common laws, have similar principles of measuring system construction, and moreover, they have common problems. Along with small values of measuring means, reaching (0,1 ÷ 1,0) % [1], and their high temperature sensitivity, up to (0,5÷1,0) °К [1,2], the uncertainty of measurement results can make hundreds of degrees. The low accuracy of temperature identification as a result of non-adequacy of the accepted mathematical model of a temperature measurement object due to eradiation and real physical phenomena belongs to shared disadvantages. The main factors causing the uncertainty of a measurement result are presented in the figure 1. The mathematical model of the output signal of pyrometric transformer, which takes into account all the factors viewed above is shown by equation: