Where the SBU found "state secrets"
Two young men - Oleksy Rud and Serhiy Chychotka - have been held in custody for almost two years, Professor Volodymyr Chumakov is facing the same charges of state treason through spying for China. What Ukraine’s SBU [Security Service] believe to be incriminating evidence is all presented below. These are the excerpts from Chumakov’s textbook, largely compiled from open resources, on the subject of railguns.
Conclusions regarding possible application of ordinary configuration railguns
1) Analysis of the results of theoretical modelling of the acceleration process of a projectile with 3 kilogram mass to the speed of 3, 000 metres per second at the railgun acceleration channel output (diagram 2.1) in erosion-free conditions showed that the electrode length exceeded 50 m. Such sizes make them unsuitable for practical use. 2) Increase in velocity given a particular barrel length can be achieved in a railgun with distributed electrodes. Analysis demonstrated that for a projectile with 2 kilogram mass to achieve a speed of 3 km/s, there need to be at least 6 rails in the accelerating system.
The experimental research was aimed at checking whether erosion-free acceleration of projectiles is possible. It was found that with initial velocity of around 10 m/s for linear density of a current under 6 kA/mm, no surface electrode erosion was observed. This result corresponds well with theoretical calculations. Low-mass projectiles can gain this initial velocity through the formation of a gas-dynamic mixture with an electric blast of a plasma insert given the closed opening of the trunk from the breech side. In the experimental railgun setup on diagram 2.6, with barrel length of 50 cm., a projectile with 2.5 g. mass was accelerated to 1 km/s. Theoretically, in erosion-free conditions, such a mass could reach 2 km/s at a length of 50 cm.
A number of experimental studies in laboratory conditions have been carried out on propulsion of projectiles in a rail accelerator with a long acceleration channel. The functional layout of the experimental stand can be found at diagram 2.7a.
Diagram 2.7 - Structural layout and general appearance of a railgun (the images can be seen here: http://chumakov.hol.es/X_Files/File_3.pdf (p. 38)
The following elements can be seen: 1- accelerated projectile; 2 – armature (plasma piston); 3 – accelerator electrodes; 4 – dielectric inlay isolating the rail contacts; 5 – dielectric filler; 6 – external shell (casing) safeguarding the stability of the system; 7 – electricity supply to the accelerator.
Theoretical modelling was carried out of the acceleration of a projectile with 3 kg mass, taking friction and head resistance into account [formulae (2.6), (2.8), (2.10), (2.12)]. The acceleration length chosen corresponds to L = 15 m. projectile velocity at barrel channel output v 3000 m/s. Solution of the task shows that to ensure the chosen characteristics, the projectile needs preliminary acceleration with an initial velocity of no less than v 0 = 400 m/s; distance between the electrodes of no less than d = 150 mm. The section of the channel for d = 150 mm is in the form of a square; linear induction constitutes L=6·10-7 gega newtons per metre. The strength of the current in the main circuit is equal to I =360 kA, the strength of the forcing current is around I Ф = 3, 6 МА, the time for the acceleration of the projectile is approximately 8.5 ms. The co-efficient for the transformation of electrical energy in the railgun into kinetic energy of the propelled projectile of 35%. Consistency of linear inductiveness is ensured through the profile of the electrodes, the cut of which changes along the barrel according to a particular law (diagram 2.4.c)
Analysis shows that the main directions in studying systems for electro-dynamic acceleration of masses will include modelling a process for acceleration of masses in order to determine the optimum conditions for acceleration and to coordinate the work of the energy accumulator and load. Studies are being carried out of the optimum constructions for accelerating systems, form and materials of the accelerated projectiles.
The results of theoretical and experimental research and achievements in creating rail electro-dynamic mass accelerators demonstrate that with a given barrel length for accelerating projectiles of a given mass to supersonic speed, the most promising type of accelerators are the following systems:
1) magnetoplasmic railgun developed according to a multi-rail setup with no less than 6 rails. In this kind of system the condition of erosion resistance is ensured, as well as the possibility of reaching a speed of around 3000 m/s at acceleration channel length of up to 15 m.
2. magnetoplasmic railgun with the forcing of a magnetic field according to this or that setup. The conditions for erosion resistance and the requirements for system durability are provided for. Optimization of temperature conditions and heat stability of the system is ensured through the profiling of the accelerator rails in accordance with the given law and through the formation of the relevant time dependence of the current impulse.