DEVELOPMENT OF AN EXPERIMENTAL AIR BLAST GAUGE.
BALLISTIC RESEARCH LABS ABERDEEN PROVING GROUND MD
Pagination or Media Count:
A baffled type gauge, called the Pancake Gauge, was the first shape to be tried. The Pancake Gauge contained four silvered tourmaline crystals, one inch in diameter and 0.040 in thick. Two crystals were mounted in each side of a brass housing. The housing was bolted into a baffle, to give the desired aspect ratio of 101, and suitable connections were made to a four foot piece of Simplex Neoprene Cable No. 178. The stack and connections were insulated and the gauge was filled with a way to present a smooth surface on both sides. The pancake gauge, as statically calibrated, had a sensitivity of about 37 micro-micro-coulombspsi which was more than sufficient for the dynamic tests. A great deal of difficulty was encountered in soldering the crystals together. In the first attempt the resistance was down on one side of the stack. The exact cause was undetermined but it was believed that, since tourmaline is often porous, some solder may have made contact through the crystal to the housing. The soldered gauge was also returned from the field with low resistance after being subjected to rather severe weather conditions.
- Test Facilities, Equipment and Methods