Development of the Device for Thick Fuel Layered Cryotarget Formation.
Tech Area / Field
- FUS-ICS/Inertial Confinement Systems/Fusion
8 Project completed
Senior Project Manager
Karabashev S G
FIAN Lebedev, Russia, Moscow
- State Enterprise Krasnaya Zvezda, Russia, Moscow
- Los-Alamos National Laboratory, USA, NM, Los-Alamos\nW. J. Shafer Associates, Inc., USA, CA, Livermore\nRochester University / Institute of Laser Energetics, USA, NY, Rochester
Project summaryThe goal of the Project is to complete the physics and engineering base to create a new technology and its associated equipment capable of fabricating thick layered cryogonetic fuel capsules for application to ICF.
Technical approach has the bases in a new method for cryogenic target formation during its downward fall inside a vertical vacuum tube (layering channel) cooled outside, that prevents stationary thermal-gradient advent. A side benefit here is the possibility to use layering channel as an injector of the layered targets at laser beam convergence or transport system to the suspender.
Expected results are the following:
1) Simulation code to provide "data base" information on the operation regimes of a special system to fill the polymer capsules with highly pressurized gas fuel (D2 or DT up to 1000 atm at room temperature) and to transport them into the layering module without mechanical rupture after pressure release.
2) A new technology to obtain cryogenic layers on the inside surface of a spherical polymer shell. The layer thickness is more than 50mm. Layer material is D2 or D2+H2 mixture modeling, in our case, the behavior of the DT fuel.
3) Complex of the equipment to fabricate thick layered cryogenic capsules and the results of its practical testing.
The complex incorporates the following:
- to fill the capsules up to 1000 atm at room temperature, including the unit to transport fuel-filled capsules into the layering module;
- layering module, including the unit to inject the layered capsules into the simulation chamber or into the target chamber;
- simulation chamber;
- system to control the complex operation.
4) Proposals on the extension of the technique developed and the equipment constructed for the DT capsules, as well as, on the application of the complex subsystems as components of the target insertion techniques.
Summary of the main results of ISTC project #512
1.Development of a broad physical and mathematical base for modeling (a) the diffusion fill process of polymer shells with hydrogen isotopes and mixtures of these gases to an internal pressure in the range of 100 – 1000 atm at 300 K, and (b) the filled- shells transport between fundamental elements of the target system: shell container - layering module - test chamber. The results obtained during simulation code development underlie the design philosophy and the construction of the fill station operating with 10/25 free-standing shells of one millimeter diameter at one time.
2. A new technology for fabricating thick layered cryogenic fuel capsules based on FST. The FST was proved to be suitable for the formation of cryogenic thick layers (Н2, D2) in the range of 30 – 100 m for 8 - 12 sec. The physical concept development and mathematical modeling of the FST- layering allow to optimize the experimental parameters for increasing the output of high- quality cryogenic targets.
3. A prototype of the free-standing target system for mass- production of ICF targets, including the system for filling polymer shells with gaseous fuel up to 300-1000 atm at 300 K; the layering module; the optical test chamber; the cryogenic target characterization system; the transport mechanisms between inpidual elements of the system. It was experimentally proved that the free-standing target concept allows to minimize time and space for all production steps. As for today, the prototype prepares up to 25 cryogenic targets in one experiment. The design of the target system allows to increase the target output up to 500 and more per day. In addition, the layering module can be adopted for using it as an injector of cryogenic targets to the ICF target chamber.
4. A method for univalent target characterization. Our analysis have shown that further progress in solving the problem of target characterization requires the development of tomographic information processing methods. To meet the reconstruction algorithm goal we have started the work on creation of a high resolution algorithm by symmetrizing a basic filtered backprojection (FBP) algorithm. The numerical experiments on testing the basic and symmetrized FBP algorithms in parallel scanning scheme have shown that the resolution of the latter is 4 times higher. To meet the scanning scheme goal we propose to use a new approach to micro-object scanning based on quasi- uniform geometry. The obtained results underlie the proposal for a new ISTC project # 1557 “Creation of a prototype of the tomographic imaging system using quasi- uniform geometry for application to inertial confinement fusion”.
Thus, in the scope of ISTC project # 512 all expected results have been obtained using free-standing targets in each production step. This approach allows for profitable operation of the target system, namely: inexpensive mass production of ICF targets and their rep- rate delivery at the laser focus under conditions of minimizing time and space for all production steps.
The project participants feel very thankful to the ISTC Secretariat, administration of the Lebedev Physical Institute of RAS and «Red Star» SE, and also to the foreign collaborators, whose support and constant help with the project allowed its successful and timely completion. We are indebted and thankful to the Acting Senior Project Manager from the ISTC, S.G.Karabashev for his understanding, valuable advice and help in communication with the ISTC officials. We are also thankful to L.M.Mitina for her help and attention. The participators of the project are most sincerely thankful to Prof. C.D. Hendriks and Dr. J.Hoffer for the constant support of the project, conceptual analysis of the obtained results and fruitful discussions which have lead to arising some new promising directions in the research of Russian scientists and engineers.
The International Science and Technology Center (ISTC) is an intergovernmental organization connecting scientists from Kazakhstan, Armenia, Tajikistan, Kyrgyzstan, and Georgia with their peers and research organizations in the EU, Japan, Republic of Korea, Norway and the United States.
ISTC facilitates international science projects and assists the global scientific and business community to source and engage with CIS and Georgian institutes that develop or possess an excellence of scientific know-how.