METHOD FOR PRECISE MEASURING THE TEMPERATURE OF COMBUSTION GAS WITH TWO THERMOCOUPLES

A method for measuring the temperature of combustion gas by two thermocouples is provided to compensate the loss of heat generated by radiation by using two thermocouples instead of using any additional expensive and complex equipment, thereby measuring the combustion gas temperature precisely at low cost. A method for measuring the temperature of combustion gas by two thermocouples includes the steps of measuring combustion gas temperature respectively by using first and second thermocouples(10,20) which have different bead diameters, and obtaining the combustion gas temperature by formulae 1 and 2. Wherein, when the flames of the combustion gas becomes normal in the first and second thermocouples and temperature, TD1 and TD2 respectively represent the temperatures of the first and second thermocouples, D1 and D2 respectively represent the bead diameters of the first and second thermocouples, sigma represents Stefan-Boltzmann's constant, epsilon represents bead emissivity, T∞ represents atmospheric temperature, and Tg represents the thermal conductivity of the combustion gas.