Evaluation of Mechanically-Aspirated Temperature/Relative Humidity Radiation Shields

The performance of the NCAR/EOL low-power, mechanically-aspirated radiation shield is compared to that of two commercial radiation shields, using air temperature calculated from the measured speed-of-sound as a radiation-error-free reference. The NCAR shield is also compared to a thermodynamic model of radiation shield performance that is a function of incoming and outgoing, longwave and shortwave radiation and ambient wind speed, as well as the geometry and materials of the shield. The NCAR shield is found to outperform the commercial shields despite using lower power for aspiration.