A NOVEL EXPERIMENTAL METHOD TO MEASURE INSTANTANEOUS PRESSURE INSIDE A POWER CARTRIDGE USING VELOCITY TEST RIG AND PROJECTILE VELOCITY BY DOPPLER RADAR

摘要

The present article explains about the novel experimental method to measure the instantaneous pressure generated by propellant burning inside the cartridge case. The instantaneous pressure was evaluated with the help of data acquisition system in a specially designed and fabricated test rig named as velocity test rig (VTR). Doppler RADAR (radio detection and ranging) is used to measure the velocity of nylon projectile. A novel method or technique was devised to measure the instantaneous pressure inside the cartridge for launching such projectile. An experimental test set-up was fabricated to measure the propellant gas pressure in a VTR. The maximum projectile velocities for NGB 051 propellants and spherical ball powder were evaluated experimentally as 420.13 m/s and 384.23 m/s respectively. The maximum pressures for NGB 051 and spherical ball powder propellants were evaluated as 63.2 MPa and 52.18 MPa respectively. The standard deviation between the experimental values for the projectile velocity is 5.49 for NGB 051 whereas it was 12.53 for spherical ball powder propellant.