Analysis of Projectile Motion in Bore and Transfer Efficiency for Electromagnetic Railgun
Electromagnetic railgun (EMG) use a high-current, high-energy electrical pulse to accelerate projectiles to hypersonic velocities. A pulsed power supply (PPS) that employ capacitors as the energy store are typically used to shape the required electrical pulse. In this paper, the differential equations of projectile moving in the bore has been given and solved. The general pattern of projectile moving in the bore has been studied. Considering the influence of current fluctuation on velocity, the stability of armature has been discussed. In order to improving system performance, the efficiency of main energy transfer process has been calculated. The influence of current shape consists of several electrical pulse on muzzle velocity and efficiency has been studied. And some important conclusions have been reached, which provide theoretical references for guiding railgun design and choosing waveform of discharging current.
MAGRAC--A railgun simulation program
We have developed and validated a computer simulation code at the Lawrence Livermore National Laboratory (LLNL) to predict the performance of a railgun electromagnetic accelerator. The code, called MAGRAC (MAGnetic Railgun ACcelerator), models the performance of a railgun driven by a magnetic flux compression current generator (MFCG). The MAGRAC code employs a time-step solution of the nonlinear time-varying element railgun circuit to determine rail currents. From the rail currents, the projectile acceleration, velocity, and position are found. We have validated the MAGRAC code through a series of eight railgun tests conducted jointly with the Los Alamos National Laboratory. This paper describes the formulation of the MAGRAC railgun model and compares the predicted current waveforms with those obtained from full-scale experiments.
Phytochemical and FT-IR Spectral Analysis of Certain Bamboo Species of SouthIndia
Bamboo with its varied uses has historically been an integral part of livelihoods and lifestyles in India. The present study was carried out to characterize the bioactive constituents present in the leaf extracts of certain bamboo species using Fourier transform infrared spectroscopic analysis (FT-IR). The various solvent extracts of various bamboo leaves subjected to qualitative analysis showed the availability of phytoconstituents including alkaloids, phenolic compounds, flavonoids, saponins, glycosides, terpenoids, steroids, coumarins and phytosterols. Quinones were completely absent in all the five bamboo species. The FT-IR spectrum confirmed the presence of sulphides (SS), phenols (C-O), aromatic compounds, thiols (S-H), aliphatic compounds (C-Cl) and amines (NH) in different bamboo species. The present investigation has also opened avenues for further research into the development of potent phytomedicines from different bamboo species.