Studies on Measurement Accuracy of the Optical Fiber Thermometer (2nd Report; Error Factor and Calibration Method of Flame Temperature Measurement)

摘要

Error factors were investigated in measurement of diesel flame temperature by means of the optical fiber thermometer (OFT), and the following techniques were proposed in the present paper to measure the flame temperature accurately. (1) The calibration method by means of the black-body furnace and the reference light-pipe sensor for obtaining the accurate sensor characteristics. (2) The appropriate correcting method for compensation of a decreased OFT-output due to sensor contamination. (3) Measurement under the steady engine operation condition and under the condition of a small OFT-output fluctuation. (4) Strictly simultaneous sampling of a couple of OFT-output data. The influence of the selected couples of two-waves, that is, the visible two-color and the infrared two-color, on the flame temperature and the soot concentration parameter KL was compared, and in addition, the simplified two-color method was proposed and also compared with the above two-color method.