Charge generation test

Uj) Telemetry Tests (Low Spin and Low Acceleration). The purpose of these tests is to investigate the performance of fuzes used with ammunition of low acceleration and spin parameters, such as the recoilless rifle and mortar projectiles. The techniques require the use of FM transmitters potted into the projectiles for transmitting such information as switch closure and electrical charge generation in flight. The telemetry transmitting station, like the transmitter in the round, are both assembled from std radio components modified for these particular tests (p IIIB-22 of Ref 39)... 

Numerous compounds have been tested and applied commercially as charge-generation and charge-transport materials, as can best be seen from the book by Borsenberger and Weiss [4]. 

The measurement of triboelectric charge generation is well known for its variability where relative humidity, surface contamination or abrasion, tress configuration, and other variables have to be strictly controlled. Even with the combing of up to five replicate tresses and five successive determinations, Lunn and Evans report a 95% confidence interval of 15%. The apparatus that Lunn and Evans used is shown in Figure 28. The insulated tress is combed with a hand-held insulated test comb, and after the appropriate number of strokes, the tress is released into a Faraday cage connected to an electrometer. The whole setup is enclosed in a box in which temperature and humidity are controlled. 

Another electrification technique involves rolling a ball of test material for study in a cyhnder separated by an insulator. The two halves of the separated cylinder are then connected to an electrometer for measurement of the charge generated in the system. Peterson (1954) and Wagner (1954) have studied static electrification in this manner. Several observations may be made from these studies ... 

The measurement of the linear velocity as a function of shaft RPM can be done at room temperature and pressure in air. It is best to do this on the catalyst already charged for the test. Since u is proportional to the square of the head generated, the relationship will hold for any fluid at any MW, T, and P if the u is expressed at the operating conditions. The measurement can be done with the flow measuring attachment and flow meter as shown in Figure 3.5.1. 

---