Question

A thermometer is used to measure the temperature of a gas flow through a pipe. The gas
temperature is read at 500°C and the duct temperature is measured to be 350°C. The thermometer
is cylindrical with a diameter of 1 mm and an intrusion length of 1 cm. It can be
assumed that the conductivity of the thermometer material is the same as stainless steel,
about 20 W/m-K. The emissivity of the thermometer tip is 02. The convective heat-transfer
coefficient between the thermometer and the gas is estimated to be 100 W/m2 -K. Estimate
the error in reading the gas temperature. Calculate the actual gas temperature.