TEMPERATURE MEASURING INSTRUMENT FOR HIGH-TEMPERATURE, HIGH-SPEED GAS, AND MEASURING METHOD THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide a temperature measuring instrument for a high-temperature, high-speed gas, capable of measuring the temperature of a high-temperature, high-speed gas with high accuracy by minimizing the effect of parameters dominating heat conduction and capable of simultaneously measuring a plurality of portions with ease, and to provide a measuring method therefore. SOLUTION: This instrument is equipped with a cooled shield 12 opened toward both the upstream side and the downstream side, a first choke flow nozzle 14 provided in the upstream-side opening part, a second choke flow nozzle 16 provided in the downstream-side opening part, a temperature detector 18 disposed in the cooled shield, and a negative-pressure chamber 20 airtightly connected to the downstream side of the cooled shield. (A) In calibration, the true temperature Tu of a gas is found from a condition that flow parameters are constant with the interior of the chamber 20 kept at a certain negative pressure and with a flow through the throats of the first and second nozzles 14 and 16 kept in a critical state. A relation between the temperature Tu and a temperature Tg measured by the detector 18 is previously found and used as calibration data. (B) In measurement, a measurement temperature Tg is measured by the detector with the critical state held, and the true temperature Tu of a gas is found from this by using the calibration data.