RADIATION AND RECOVERY CORRECTIONS AND TIME CONSTANTS OF SEVERAL CHROMEL-ALUMEL THERMOCOUPLE PROBES IN HIGH-TEMPERATURE, HIGH-VELOCITY GAS STREAMS

摘要

Radiation and recovery corrections and time constants were experimentally determined for several designs of shielded and unshielded thermocouple probes using chromel-alumel wire. Radiation and time constant data were obtained for Mach numbers from 0.3 to 0.9, static pressures From 2/3 to 1 1/3 atmospheres, and temperatures from 1500° to 8500° R. Recovery data were obtained for Mach numbers from 0.2 to 0.9 and static pressures from 1/7 to 1 2/3 atmospheres, at room total temperature. A re view of the theory of gas temperature measurements and an analysis of the data show that simple empirical formulas can be used to correlate corrections for various gas-stream conditions. Tables and graphs are presented which show the correction factors of the various designs to aid in selecting a probe for a particular application.