Neutron and high speed photogrammetric arcjet diagnosisTwo methods for real time internal diagnostics of arcjet engines are described. One method uses cold, thermal, or epithermal neutrons. Cold neutrons are used to detect the presence and location of hydrogenous propellants. Thermal neutrons are used to delineate the edge contours of anode and cathode surfaces and to measure stress/strain. Epithermal neutrons are used to measure temperatures on arcjet surfaces, bulk material temperatures, and point temperatures in bulk materials. It is found that this method, with an exposure time of 10 min, produces at temperature accuracy for W or Re of + or - 2.5 C. The other method uses visible-light high-speed photogrammetry to obtain images of the transient behavior of the arc during start-up and to relate this behavior to electrial supply characteristics such as voltage, current, and ripple.
Document ID
19890059826
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Stewart, P. A. E. (Rolls-Royce Ltd. Bristol, United Kingdom)
Rogers, J. D. (Rolls-Royce PLC, Bristol, United Kingdom)
Fowler, P. H. (Bristol, University United Kingdom)
Deininger, W. D. (California Institute of Technology Jet Propulsion Laboratory, Pasadena, United States)
Taylor, A. D. (SERC Rutherford Appleton Laboratory, Didcot, United Kingdom)