一种空间燃料电池电源系统设计与实现

面向空间应用,依据某航天器任务期间的功耗需求,采用燃料电池和蓄电池的架构,对1kW燃料电池电源系统的设计与实现进行研究。构建了1kW燃料电池电源系统仿真模型,对系统设计原理进行了仿真验证,并研制了1kW燃料电池电源系统样机,对系统典型的负载阶跃工况进行了试验测试。试验测试结果表明,1kW燃料电池电源系统在半载阶跃变化时,母线电压波动小于5V,调节时间小于25μs;整个运行过程系统工作正常稳定,能够满足航天器空间应用需求。     

Fast measurements of parameters of the Solar Wind using the BMSW instrument

Design of the plasma spectrometer BMSW (Fast Monitor of the Solar Wind, possessing high temporal resolution) is described in the paper, as well as its characteristics and modes of operation. Some examples of measurements of various properties of the solar wind, made with this instrument installed onboard the high-apogee satellite Spektr-R, are presented.     

Solution of the five-layer beam bending problem using the calculus of variation

The paper deals with the problem of lateral bending for the five-layer panel with the lightweight filler that is reduced to the bending problem of a beam fixed at the end sections. To solve the differential equations describing the beam bending, the Euler-Lagrange variational principle is used.     

Formation of programmed spatial flight trajectories of unmanned aerial vehicles

In this paper, we introduce a concept of coordinated turn that means the application of the lifting force being perpendicular to the UAV velocity vector and parallel to the surface on which the exact point target is located. Analytical solutions of the corresponding differential equations of the coordinated turn are derived.     

The effect of detuning of the partial frequency of MEMS gyros sensing elements on the amplitude-frequency response

The effect of detuning the partial frequencies of MEMS gyroscopes on its amplitudefrequency response is investigated. The formulated mathematical model allows defining requirements for the tolerances on gyros parameters, which determine the values of gyros partial frequencies, at the design stage of the sensor.     

The 3D Computational Investigation of Film Cooling Effectiveness for Turbine Nozzle Vanes with “Meridian Constriction” and Shaped Film-Cooling Holes

Active influence dimension of film cooling along the blade profile is investigated with using the Spalart–Allmaras turbulence model. The cooling effectiveness of vane platforms and vane fillets is studied with the use of perforation holes on the leading edge.     

Determination of Slag Retention Ability of Gating Systems

The paper highlights results of analyzing the gating systems in terms of assurance of slag retention at the stage when the mold cavity is filled up with the melt. Quantitative values of parameters as to assessment of slag retention were obtained that can be applied in selecting the gating system type for a casting.     

Reusable Space Transportation System

We present a design lay-out diagram of the reusable space transportation system that consists of an aerospace transformed vehicle that is injected into an orbit by means of the first and second stages. Some starting configurations of such system with the first and second stages are considered.     

Old-Aged Primary Distance Indicators

Old-aged stellar distance indicators are present in all Galactic structures (halo, bulge, disk) and in galaxies of all Hubble types and, thus, are immensely powerful tools for understanding our Universe. Here we present a comprehensive review for three primary standard candles from Population II: (i) RR Lyrae type variables (RRL), (ii) type II Cepheid variables (T2C), and (iii) the tip of the red giant branch (TRGB). The discovery and use of these distance indicators is placed in historical context before describing their theoretical foundations and demonstrating their observational applications across multiple wavelengths. The methods used to establish the absolute scale for each standard candle is described with a discussion of the observational systematics. We conclude by looking forward to the suite of new observational facilities anticipated over the next decade; these have both a broader wavelength coverage and larger apertures than current facilities. We anticipate future advancements in our theoretical understanding and observational application of these stellar populations as they apply to the Galactic and extragalactic distance scale.