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работ в послеаварийный период. Представленный анализ действий японской стороны и международных организаций по смягчению и ликвидации последствий аварии и известные результаты моделирования распространения радиоак-тивных продуктов в окружающей среде позволяют сделать важные шаги в понимании основных причин, уроков и последствий большой аварии на АЭС Fukushima-Daiichi. Полученные оценки носят предварительный характер и предполагают дальнейший мониторинг и анализ развития вопросов по обеспечение экологической безопасности и устранению последствий аварий на АЭС.Ключевые слова: Фукусимская авария, экологические последствия, радиоактивные выбросы.I.L. Kozlov. Analysis of ecological consequences and lessons of the Fukushima accident. The events that occurred at the nuclear power plant (NPP) Fukushima-Daiichi forced all the world nuclear community and government bodies of ecological safety regulation to return again, after Chernobyl accident, to the need of revaluating the safety of all operating and designed NPPs. The consequences connected with emissions of radioactive products to the environment increase the validity of studying and analyzing the environmental issues, while evaluating the works done in the postemergency period. The presented analysis of the actions of the Japanese side and of the international organizations on mitigation and elimination of consequences of the accident, as well as the results of modeling of radioactive products distribution in environment allow to take important steps in understanding the main reasons, processes and consequences of the big accident on the nuclear power plant Fukushima-Daiichi. The obtained estimates are preliminary and require further monitoring and analysis of issues on ecological security and elimination of consequences of accidents at NPPs.

6 (accompanying the shell flight) and muzzle (created by powder gases flowing out of the gun barrel under high pressure). To determine coordinates of the firing gun, acoustic waves can be recorded by a system of spaced microphone sensors. In 1. Introduction Powerful acoustic fields are formed with each artillery shot. These fields are mainly formed by two waves: ballistic

Introduction. Multidimensional flame instability (two-dimensional instability as its special case) is well investigated analytically [1, 2]. Such kind of instability leads to distortion of the flame front [1, 2] and causes cellular structure of flame and turbulent combustion [3]. Multidimensional flame instability can be also the reason of deflagration-to-detonation transition (DDT) [4]. But there are not many theoretical investigations of flame stability for one-dimensional case. This fact is entirely understandable since realization of one-dimensional instability is impossible under development of multidimensional perturbations in case of the instable flame front. Still the case of onedimensional flame instability is rather important from practical point of view for situations when multidimensional perturbations can't develop because of boundary conditions (for example the wave length m λ that corresponds to the perturbation with the fastest growth rate of amplitude is more than the tube diameter or the channel width). One-dimensional flame instability can be the reason of vibratory combustion in fire-chambers [5]. This regime causes rapid variation of pressure and velocity in space and time. The increased pressure perturbations wreck the walls of chamber and can destroy it completely. By the way powerful longitudinal pulsations can ruin the process of burning. Since there is problem of the fire-chamber control to prevent flame from intensive oscillations and vibrations. Literature review. On the one hand vibratory combustion [5] is rather well studied by L. Crocco, S.-I. Cheng, B. Raushenbach, M. Natanson. Proceedings of V.V. Gotsulenko [6, 7] contain modern interesting ideas and thoughts of the flame oscillations and their control. But on the other hand the problem of the vibratory combustion development is still unsolved. There are no fully clear theoretical explanations (neither mathematical nor mechanical and physical) for longitudinal pulsations of pressure and velocity in the direction of the tube axis or channel axis. This work is only an attempt (may be primitive enough) to explain the origin of such perturbations at least mathematically, from the point of view of gas dynamics, without analyzing any physical and chemical reasons. Aim of the Research is to investigate one-dimensional stability of flames in closed tubes, channels and chambers; to ground mathematically the control of burning in fire-chambers. Main Body. Mathematical model. The following mathematical model of combustion is considered (Fig. 1). Along x-axis, at < 0 x , the ideal inviscid gas moves at a stationary subsonic velocity 1 u (1 u is much less than the sonic speed 1 a ; velocity 1 u equals the burning rate or the fuel supply rate). Plane = 0 x corresponds to the flame front. Planes V.E. Volkov. One-dimensional flame instability and control of burning in fire-chamber. The flame stability with regard to one-dimensional exponential perturbations both for the combustion in the fire-chamber and the flame propagating in closed tubes or c...