Modeling of cooling processes in the variable section channel of a gas conduit

Using the results of numerical modeling of nonstationary gas hydrodynamic working processes in the gas conduit variable section channel when removing and cooling hot gases of different purpose technical plants, an engineering technique has been developed to provide the gas conduit operation under limitations on the flow temperature in the outlet plant section. A multiparametric area of permissible gas conduit operation connecting the characteristics of technical plants, gas conduit and water feeding system is presented.     

Gravitropism and phototropism in protonemata of the moss Pohlia nutans (Hedw.) Lindb.

The gravitropism of protonemata of Pohlia nutans is described and compared with that of other mosses. In darkness, protonemata showed negative gravitropism. Under uniform illumination they grew radially over the substrate surface, whereas unilateral illumination induced positive phototropic growth. Gravitropism was coupled with starch synthesis and amyloplast formation. Protonematal gravitropic growth is more variable than the strict negative gravitropism of Ceratodon chloronema.     

Anthropogenic trigger of substorms and energetic particles precipitations

The high-frequency (HF) emission in near-Earth space from various powerful transmitters (radio communications, radars, broadcasting, universal time and navigation stations, etc.) form an integral part of the modern world that it cannot do without. In particular, special-purpose research facilities equipped with powerful HF transmitters are used successfully for plasma experiments and local modification of the ionosphere. In this work, we are using the results of a complex space-ground experiment to show that exposure of the subauroral region to HF emission can not only cause local changes in the ionosphere, but can also trigger processes in the magnetosphere–ionosphere system that result in intensive substorm activity (precipitations of high-energy particles, aurorae, significant variations in the ionospheric parameters and, as a consequence, in radio propagation conditions).     

火箭冲压组合动力研究进展

对国内外火箭冲压组合动力(RBCC)研究现状与发展路线进行了总结，阐述了各国主要研究计划和取得的重要成果。系统地总结了西北工业大学航天学院在火箭冲压组合动力的研究进展和研究成果，经过近二十年的发展，完成了从发动机理论分析与原理验证、部件设计与试验到小尺度发动机地面集成验证，初步突破和掌握了宽域全流道设计、宽来流高效燃烧与火焰稳定以及模态过渡等多项关键技术，具备了开展飞行演示验证的基础。     

详细初步设计阶段使用与维修保障同步设计方法研究

从工程应用角度基于IPT工作模式,建立详细初步设计阶段以电子样机、虚拟仿真技术等为手段,同步开展使用与维修保障设计分析的流程和方法。以某型飞机舵机A为实例,对建立的方法进行应用,实践表明,建立的方法适用、有效、符合工程实际。该方法的建立,将对详细初步设计阶段一级IPT成员同步开展使用与维修保障设计、分析工作提供有力的技术支撑,对提高军用飞机使用与维修保障设计水平具有重要意义。     

MSCSG转子系统的扩展双频Bode图稳定性分析方法

为分析洛伦兹力磁轴承驱动磁悬浮控制敏感陀螺（MSCSG）转子偏转过程中的稳定性，针对现有双频Bode图稳定性判据方法仅适用于最小相位系统的不足，提出一种基于扩展双频Bode图的稳定性分析方法。根据洛伦兹力磁轴承工作原理建立了MSCSG转子偏转系统动力学模型；通过变量重构，将实系数双输入双输出系统等效变换为复系数单输入单输出系统；在分析Nyquist曲线与Bode图关联性的基础上，提出针对非最小相位系统的扩展双频Bode图稳定性判据，对不同转速下MSCSG转子系统稳定性进行预测，并通过转速根轨迹曲线预测转子系统的转速稳定区间。所提出的扩展双频Bode图稳定判据结果与时域仿真校验结果相一致，验证了本文所提出的稳定性分析方法的正确性和有效性。     

A new inversion method of plasma density distribution of plasmasphere in the geomagnetic equatorial plane from IMAGE data

The plasma density distribution of plasmasphere in the geomagnetic equatorial plane can help us study the magnetosphere like plasmasphere, ionosphere and their kinetics. In this paper, we introduce a new inversion method, GE-ART, to calculate the plasma density distribution in the geomagnetic equatorial plane from the Extreme Ultraviolet (EUV) data of IMAGE satellite under the assumption that the plasma density is constant along each geomagnetic field line. The new GE-ART algorithm was derived from the traditional Algebraic Reconstruction Techniques (ART) in Computed Tomography (CT) which was different from the several existing methods. In this new method, each value of the EUV image data was back-projected evenly to the geomagnetic field lines intersected by this EUV sight. A 3-D inversion matrix was produced by the contributions of all the voxels contained in the plasmasphere covered by the EUV sensor. That is, we considered that each value of the EUV image data was relative to the plasma densities of all the voxels passed through by the corresponding EUV radiation, which is the biggest difference to all the existing inversion methods. Finally, the GE-ART algorithm was evaluated by the real EUV data from the IMAGE satellite.     

Simulation of the test stand gas-liquid ejector operation

Based on the data of numerical simulation of the test stand gas-liquid ejector operation, the fields of gasodynamic flow parameters in the gas flue channel are determined. The test stand operation in real time and processes of interaction between the flow of combustion products and neutralizing liquid are also analyzed.     

Some features of solar cosmic ray penetration into the Earth’s magnetosphere

We compared fluxes of the 1–100 MeV solar energetic particles (SEP) measured in the interplanetary medium (ACE) and in the magnetosphere (Universitetsky-Tatiana, POES—in polar caps, and GOES-11—at geosynchronous orbit) during several SEP events of 2005–2006. Peak intensities of the SEP fluxes inside and outside the magnetosphere were compared for each event. It is shown that observed inside-outside difference depends mainly on direction of interplanetary magnetic field (IMF), on degree of the SEP anisotropy (pitch-angle distribution) in IMF, and on distance of the dayside magnetopause from the Earth.