128 research outputs found

    The importance of modern information technologies in development of distance education

    Get PDF

    Determination of the propellant combustion law under ballistic experiment conditions

    Get PDF
    The main characteristics of ballistic experiment are the maximum pressure in the combustion chamber P max and the projectile velocity at the time of barrel leaving U M. During the work the burning law of the new high-energy fuel was determined in a ballistic experiment. This burning law was used for a parametric study of depending P max and U M from a powder charge mass and a traveling charge at initial temperature of + 20 °C was carried out. The optimal conditions for loading were obtained for improving the muzzle velocity by 14.9 %. Under optimal loading, there is defined the conditions, which is possible to get the greatest value muzzle velocity projectile at pressures up to 600 MPa

    On the Wigner function of the relativistic finite-difference oscillator in an external field

    Full text link
    The phase-space representation for a relativistic linear oscillator in a homogeneous external field expressed through the finite-difference equation is constructed. Explicit expressions of the relativistic oscillator Wigner quasi-distribution function for the stationary states as well as of states of thermodynamical equilibrium are obtained and their correct limits are shown.Comment: 12 pages, 6 figures, IOP styled LaTeX, to be published in Journal of Physics

    Mathematical model and software for investigation of internal ballistic processes in high-speed projectile installations

    Get PDF
    This paper describes a software package that allows to explore the interior ballistics processes occurring in a shot scheme with bulk charges using propellant pasty substances at various loading schemes, etc. As a mathematical model, a model of a polydisperse mixture of non-deformable particles and a carrier gas phase is used in the quasi-one-dimensional approximation. Writing the equations of the mathematical model allows to use it to describe a broad class of interior ballistics processes. Features of the using approach are illustrated by calculating the ignition period for the charge of tubular propellant

    Dynamics in a noncommutative phase space

    Get PDF
    Dynamics has been generalized to a noncommutative phase space. The noncommuting phase space is taken to be invariant under the quantum group GLq,p(2)GL_{q,p}(2). The qq-deformed differential calculus on the phase space is formulated and using this, both the Hamiltonian and Lagrangian forms of dynamics have been constructed. In contrast to earlier forms of qq-dynamics, our formalism has the advantage of preserving the conventional symmetries such as rotational or Lorentz invariance.Comment: LaTeX-twice, 16 page

    Разработка технического решения по предупреждению попадания одновинтового вертолета в неуправляемое вращение

    Get PDF
    The phenomenon of a single-rotor helicopter entering an unintended left rotation with the further development of an uncontrolled turn periodically arises while operating this type of helicopter, both in Russia and abroad. This phenomenon can lead to serious aviation incidents and even disasters. Currently, there is no unambiguous justification for the phenomenon of "uncontrolled" U-turn and the causes of occurrence, since the operating conditions of the tail rotor (TR), especially at low-speed modes, depend on many factors. These factors include, firstly, wind direction and speed, T/R “vortex ring", as well as the impact of the main rotor vortex trace. One of the explanations for this phenomenon lies in the special specifics of the yaw trim of a singlerotor helicopter, which is provided by the tail rotor. These papers emphasize that the change in wind speed and direction which affects the helicopter, and the TR is the main cause of the unintentional left turn. Currently, there are no tools and methods for determining the wind effect on the TR in order to develop a warning signal for a pilot about a change in the nature of the TR flow and an alert about the occurrence of uncontrolled rotation. This paper proposes the system for measuring the TR air flow using a special sensor that allows us to measure the inductive air flow velocity of a small value in an aerodynamic way without additional various electronic transformations that are inherent in conventional Pitot tube probes. The use of such a measurement system makes it possible to identify the probability of a dangerous situation, to inform the pilot and help him take the proper actions. Явление попадания одновинтового вертолета в непреднамеренный разворот влево с дальнейшим развитием неуправляемого разворота периодически возникает в процессе эксплуатации такого типа вертолетов как в России, так и за рубежом. Это явление может приводить к серьезным авиационным инцидентам и даже к катастрофам. В настоящее время нет однозначного обоснования явления «неуправляемый разворот» и причин его возникновения, так как условия работы рулевого винта, особенно на режимах малых скоростей, зависят от многих факторов. К этим факторам относятся в первую очередь направление и скорость ветра, «вихревое кольцо» на рулевом винте, а также влияние вихревого следа от несущего винта. Одно из объяснений этого явления – особенности путевой балансировки одновинтового вертолета, которая обеспечивается рулевым винтом. Главной причиной возникновения непреднамеренного разворота влево в исследованиях указывают изменение скорости и направления ветра, действующего на вертолет и рулевой винт в частности. В настоящее время отсутствуют инструментальные средства и методика определения ветрового воздействия на рулевой винт для выработки предупреждения летчику об изменении характера обтекания рулевого винта и о возникновении неуправляемого вращения. В данной работе предлагается система измерения воздушного потока на рулевом винте с помощью специального датчика, позволяющего измерить аэродинамическим способом непосредственно индуктивную скорость воздушного потока малой величины без дополнительных различных электронных преобразований, которые присущи традиционным датчикам типа ПВД. Применение такой системы измерений позволяет определить приближение опасной ситуации, дать информацию летчику и помочь ему предпринять правильные действия
    corecore