热力学排气系统中节流效应及其冷量利用分析

为更好地理解热力学排气系统(TVS)的运行机理，优化其运行参数，针对节流装置，建立了热力学模型，讨论了节流过程中状态参数的变化规律，对比了单相气体、单相液体节流的性能特性，进一步揭示了焦汤节流效应的原理，分析了不同节流背压下节流前低温工质(液氢和液氧)压力和温度对节流性能的影响，并结合TVS实际应用，阐述了节流最大制冷量的利用效果，提出了优化的TVS工作区间。研究表明：在节流过程不发生相变情况下单相气体节流制冷效应要比单相液体节流制冷效应更加显著；而在节流过程发生相变情况下液体节流至两相后，由于空化吸热导致流体温度降低，对于液氢，0.5MPa的压降可产生接近3 K的温降。对于液体节流，节流前压力对节流过程影响可忽略，〖JP2〗而节流前温度和节流背压对节流过程起主导作用；对于液氢在在轨运行工况下，考虑到节流制冷量的充分利用，同时保证换热过程体积含气率不高于90%，推荐TVS系统中节流背压范围为75～143 kPa。     

Erratum to: Use of the DBM Model to the Predict of Arrival of Coronal Mass Ejections to the Earth

Cosmic Research - An Erratum to this paper has been published: https://doi.org/10.1134/S0010952521120017     

某型教练机嵌入式训练系统顶层设计技术研究

本文通过对该型教练机现有航空电子系统构型、驾驶员操作程序、接口控制文件深入研究,结合未来功能扩展需求,给出了合理的系统构型分析、功能分配、数据流规划、原相关系统软件改动分析,在此基础上还设计出了嵌入式训练系统技术方案.依据方案研制的嵌入式训练系统原理样机通过系统动态试验、航电系统地面综合试验和飞机地面通电试验,证明系统...     

A software package for computer-aided design analysis of thin-walled structures from composite materials

An algorithm of analyzing the design parameters for a thin-walled wing from composite material based on the efficient distribution of structural material between load-carrying elements is described. We consider the problems of convergence acceleration for the iteration design analysis. Also presented are the examples of determining the design parameters for a superlight aircraft wing and the rational parameters of the filler in the form of a three-dimensional rod structure.     

Water feed influence on nitric oxide emission under oxidation of near-stoichiometric air-methane mixtures

We considered the influence of temperature on the nitric oxide emission under combustion of the near-stoichiometric mixtures with and without water feed. We revealed the advantage of the method of fuel-water-air mixture combustion over that of the leaned mixture combustion.     

Determination of characteristic frequencies of elastic oscillations of the <Emphasis Type="Italic">International Space Station</Emphasis> construction

The results of investigating free oscillations of the International Space Station construction appearing during spacecraft docking and undocking are described. The study is carried out using the measurement data of the low-frequency MAMS accelerometer. Several intervals of measurements performed in 2005 and 2006 were chosen to be studied. For chosen intervals, only the data intervals corresponding to the process of free attenuation of the oscillations construction elements were analyzed. Characteristic frequencies of elastic oscillations of the station construction and attenuation coefficients corresponding to them are found. The comparative analysis of the results obtained for various docking ports (nodes) is carried out. The described study is performed as a part of the technical experiment “The ISS Environment” carried out onboard the station in accordance with the Russian program of scientific and engineering experiments.     

Algebraic operations on graphs with using numeric coding for simulating the systems of rocket and space technology

The paper adduces the relators for algebraic operations on graphs using the numeric codes of the graphs. The special algebra of codes has been devised with consideration of the principles of graph transformation. This paper demonstrates the relevance of numeric coding of graphs for solving the problems of enumeration, systematization, and compact representation of the information about the structural and functional characteristics of the systems of flow distribution and conversion of rocket and space technology and for conducting the modeling transformations of given systems in the course of the structural and functional studies as well.