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Title of the Paper: Generation of the Moon and Some Other Celestial Bodies due to
Explosion in Planet Interiors
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Authors: D.V.Voronin, V.F.Anisichkin
Abstract: The structure and composition of planets, small bodies of the Solar system is essentially different.
Therefore it is difficult to explain an origin of all celestial bodies of the Solar system due to smooth evolution
of the protoplanet cloud. An alternative to the evolutionary one is the hypothesis of the explosive origin of
some celestial bodies. It is supposed, that on the solid inner core of a planet the active layer is formed from
particles of uranium and thorium oxides (or carbides), weighed in liquid iron of the outer core of the planet.
The explosion in such a layer might take place at fast and deep transition of the system in a supercritical
condition, for example as a result of collision of a planet with an asteroid. Collision of the protoplanet with an
asteroid, the subsequent explosion in an active layer and partial or full fragmentation of the planet in conditions
of gravitation is numerically simulated. Modeling was conducted within the framework of hydrodynamical
approach for two-dimensional non-stationary motion of the compressible medium on the basis of laws of
conservation of mass, pulse and energy in cases of plane and axial symmetry.
The hypothesis that some bodies of the Solar system might be formed as a result of nuclear explosions in the
protoplanet core, including large enough fragments mainly iron-nickel, stone-silicate or dust-ice structure is
numerically confirmed in the paper. It explains distinctions in structure and characteristics of satellites of some
planets, asteroids and comets. Formation of small celestial bodies due to the explosion is possible at
preservation of the initial protoplanet as well. If the initial velocity of protoplanet rotation is small enough, the
structure and composition of fragments may be determined by the cumulative jet going from a planetary core to
its surface. The origin of Io (the nearest satellite of Jupiter, consisting basically from the heated iron) may be
explained, for example.
For the great enough velocity of rotation of the initial planet the cumulative jet has not determining
influence on the process of destruction. In this case the nuclear explosion in the planet interiors breaks the
balance between the centrifugal forces and the gravitation. That results in the separation of the great mass of the
stone-silicate shell of the planet and the generation of satellites like the Moon.
Keywords: numerical simulations, active layer, celestial bodies, explosion, cumulative jet, planet rotation
Title of the Paper: Modeling and Simulation of Thermal Air Circulation
above an Urbanized Area
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Authors: A. F. Kurbatsky And L. I. Kurbatskaya
Abstract: A numerical model to represent the impact of urban buildings on airflow in meso’scale turbulence models is presented. In the model, the buildings are not explicitly resolved, but their effects on the grid-averaged variables are parameterized. An urbanized area is characterized by a horizontal building size, a street canyon width and a building density as a function of height. The improved, three-parametric 2E−ε−θturbu-lence model for the computation of the wind field, air temperature and pollutant dispersion was developed. The transport of momentum, heat and mass under density stratification is evaluated from the fully explicit anisot-ropic algebraic expressions. These expressions are derived based on the assumption of weak-equilibrium turbu-lence approach where transport effects on the stresses and heat fluxes are negligible. The heating processes at surfaces of buildings and ground are also modeled. The comparison of the computational results obtained with the present model and existing observational data and numerical models shows that the present model is capable of predicting the structure of turbulence in the urban canopy layer under density stratification and of obtaining high-resolution local wind fields. Numerical experiments with the new three-parametric model show that the behavior of the airflow in the urban canopy layer and above urbanized area is strongly affected by the existence of buildings and thermal stratification, including the urban heat island effect.
Keywords: Thermal Convection, Turbulence, Planetary Boundary Layer, Modeling and Simulation
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