Experimental And Theoretical Research On The High Speed Flyer Driven By Laser

The principle, research method and applications of laser driven flyer was introduced first in this thesis. The recently development both in experiment and theory research of the laser driven flyer have been reviewed and some theory including instantly detonation model and Knight theory, Krokhin theory were also introduced in the thesis.The experimental setup and technique of laser driven flyer were build and developed in this dissertation, the highest flyer velocity of about 7km/s was obtained and good integrity and plane of flyer were confirmed. The average velocity of flyer was measured by using quartz gauge, and influence of flyer's form on the energy coupling coefficient were researched in this paper. Experiments had shown that the energy coupling coefficient of flyer formed by small hole cutting was one times more higher than free form's flyer.A body ablation model to describe laser driven flyer have been put forward in this paper. On the basis of Lagrange fluid dynamic code SSS an EOS table database was added and can finish the numerical simulation. The "stiff' difficulty caused by small size of mesh was overcome in the calculation, no vibration happens in the calculations, the theoretical results were reasonable and in according with the experimental ones. By using this model we can obtain the pressure, temperature, velocity, opacity and average ionization charge of different position and time during the process of laser driven flyer.In this thesis, the laser driven flyer device was also used as a test bed for explosive initiation and dynamic fracture experiments. It is the first times to initiate PETN explosive using laser driven flyer. The detonation threshold and POP relations of shock wave propagation of PETN under short pressure pulse were obtained. The numerical simulation on the process of laser driven flyer to initiate PETN have been done using reaction dynamic code SSS, and theoretical detonation threshold and POP relations were obtained. The theoretical results were in according with the experiments.The spall experiment caused by laser driven flyer have also been done in this dissertation. The obvious spall were found in the recovery sample under microscope. A simple numerical calculation on the spall caused by laser driven flyer have been done using SSS code and the reasonable results were obtained.