The aim of this work was to create an e©cient tool for transient threedimensional (3D) numerical simulation of the operation process in a Rotating Detonation Engine (RDE) with the particular emphasis to the design issues of the combustion chamber and isolators, thermal management and operation control. The governing equations are unsteady Reynolds-Averaged NavierStokes (URANS) equations coupled with a turbulence model and with the continuity and energy equations for a multicomponent reactive mixture. The algorithm used is the combination of Finite Volume Method and Particle Method recently developed at ICP to treat simultaneously frontal and volumetric combustion. The capabilities of the new numerical tool have been demonstrated for the annular cylindrical RDE operating on homogeneous stoichiometric hydrogen air mixture with a detonation rotation frequency of about 126,000 rpm. The calculations revealed considerable temperature and pressure pulsations at RDE inlet and outlet; however, special design adaptations were shown to allow their reduction.

A source of soft X-ray emission based on the miniature 15 kJ (9È14 Ó) plasma focus was developed and tested. The X-ray emission was channelled along the chamber axis through an opening in the inner electrode (anode). A regime with a mean output of more than 100 J per discharge was found. At a discharge current of 280 kA and repetition rate of 3.5 Hz achieved by the device, its lifetime was estimated to be 107 commutations (about a year of continuous operation). A demonstration experiment on irradiation of an X-ray resist is discussed.

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In this work, the mutual arrangement of polyelectrolytes of multilayer polyelectrolyte microcapsules (with layers—[PAH/PSS]3PAH) by determination of the dissociation level of polyallylamine (PAH) from the surface of a polyelectrolyte microcapsules (PMC) of various types was studied: PMC with a dissolved CaCO3 core after preparation, PMC with an undissolved CaCO3 core and PMC with an encapsulated protein. It was concluded that the polyelectrolyte layers are mixed in the entire shell of the capsules with a dissolved CaCO3 core. In the case of the PMC with an undissolved CaCO3 core, such mixing of polyelectrolyte layers does not occur. That fact allows us to conclude that the mixing of polyelectrolytes layers mixing at the stage of dissolution of CaCO3 core. The PMC with encapsulated protein has partial mixing of polyelectrolytes layers. That phenomenon may be due to the fact that seven-layered protein-containing microcapsules already have a dense and well-formed shell. The obtained data correlate with the data on the study of the surface charge of microcapsules.

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The aim of this work is to apply three dimensional numerical simulation to determining the con ditions of the stable operation of the rotating detonation chamber (RDC), the thermal state of the chamber walls, as well as the most important parameters of the flow at the inlet and outlet, keeping in mind the possi bility of placing the RDC between a compressor and a turbine in a prospective gas turbine installation. The model is based on a system of three dimensional unsteady Reynolds averaged Navier-Stokes, energy, and species conservation equations for a multicomponent reacting gas mixture supplemented by a turbulence model. The system is solved using a combined algorithm based on the finite volume and particle methods. The capabilities of the computer program are demonstrated by the example of a circular RDC with inner and outer walls 260 and 306 mm in diameter and with axial introduction of a hydrogen-air mixture through an annular gap at the bottom of the chamber (with a relative area of 0.6). The detonation wave spun over the bot tom at a frequency of ~126000 rpm. Calculations have shown that such an RDC can operate in a steady mode with one detonation wave.