THREE-COLOR PYROMETRY FOR TEMPERATURE MEASUREMENT OF REENTRY VEHICLE NOSETIP MATERIALS

WE PROPOSE TO INVESTIGATE THE FEASIBILITY OF CONSTRUCTING A HIGHSPEED, TWO-DIMENSIONAL PYROMETER SYSTEM CAPABLE OF MEASURING REENTRY VEHICLE NOSETIP TEMPERATURES BETWEEN 800 K AND 6000 K DURING BALLISTICRANGE GROUND TESTS. THE PHASE I EFFORT WILL FOCUS ON EXPLORING THE PYROMETER'S CAPABILITIES AT THE LOW END OF THE TEMPERATURE RANGE, WHERE THE REQUIRED SPATIAL RESOLUTION OF 0.1 IN. AND DATA ACQUISITION TIME OF 10 NANOSECONDS IMPOSE SEVERE CONSTRAINTS. A ONE-DIMENSIONAL PYROMETER WILL BE BUILT HAVING CHARACTERISTICS WHICH SIMULATE THOSE REQUIRED OF THE TWO-DIMENSIONAL SYSTEM TO TEST EXPERIMENTALLY ITS LOW TEMPERATURE SENSITIVITY. ALSO, THE FEASIBILITY OF ADAPTING A TWO-DIMENSIONAL PYROMETER TO A COST-EFFECTIVE COMPUTERIZED DATA ACQUISTION SYSTEM WILL BE EXPLORED, AND COMPONENTS WILL BE SPECIFIED FOR CONSTRUCTION OF A THREE-COLOR PYROMETER FOR FIELD USE HAVING TEMPERATURE ERRORS RESULTING FROM UNKNOWN TARGET EMISSIVITIES MINIMIZED.