- Author
- Murthy, A. V. | Wetterlund, I. | DeWitt, D. P.
- Title
- Characterization of an Ellipsoidal Radiometer.
- Coporate
- Aero-Tech, Inc., Hampton, VA SP Swedish National Testing and Research Institute, Boras, Sweden National Institute of Standards and Technology, Gaithersburg, MD
- Journal
- Journal of Research of the National Institute of Standards and Technology, Vol. 108, No. 2, 115-124, March/April 2003
- Keywords
- radiometers | heat flux | sensors
- Abstract
- An ellipsoidal radiometer has been characterized using a 25 mm variable-temperature blackbody as a radiant source. This radiometer is intended for separating radiation from convection effects in fire test methods. The characterization included angular response, responsivity, and purgegas flow effect studies. The angular response measurements showed that the reflection from the radiometer cavity was higher on one of the cavity halves relative to the other half. Further development work may be necessary to improve the angular response. The responsivity measured with reference to a transfer-standard electrical-substitution radiometer showed dependence on the distance of the radiometer from the blackbody cavity. The purge-gas had the effect of reducing the signal output nearly linearly with flow rate.