Abstract: Publication year: 2021Source: International Journal of Aerospace Sciences, Volume 9, Number 1Nickolay ZosimovychThis paper proposes a communication system for nanosatellite Earth observation preliminary design technique as useful tools for managing and improving various aspects of regional and national resources. Has been estimated and proposed a design process for the low Earth orbit nanosatellite communication system. In proposed paper on basis of structural optimization technique have been formulated and solved next goals: reviewed Earth observation systems and studied their design parameters, analyzed the on-board antennas design background and provided analytical estimations, such as design a passband quadrature phase shift keying transmitter and receiver in Simulink, was obtained a bit error rate curves by using a Simulink / MathWorks, generated an offset quadrature phase shift keying waveform and investigated their characteristics, observed and analyzed the diagrams, constellation, and the signal trajectories of quadrature phase shift keying according contemporary design concept. All this allows to propose innovative communication system design techniques applied for the nanosatellite category.
Abstract: Publication year: 2020Source: International Journal of Aerospace Sciences, Volume 8, Number 1Nickolay ZosimovychThis paper surveys and estimates the potential of one-unit CubeSat platform and reflects about design a more suitable platform for future CubeSats. During CubeSat platform development, the concept of the design process is formulated and standard physical relationships are proposed to find number of optimal design solution in terms of basic limitations and features compatibility. Specifically, new modular structure is proposed in order to allows flexible subsystems settlement. A design analysis is also presented concerning the CubeSat platform manufacturing technique. A CubeSat structure has been realized by using a rapid prototyping technique. Such choice allows to optimize a CubeSat design, manufacture, and - assembly.
Abstract: Publication year: 2019Source: International Journal of Aerospace Sciences, Volume 7, Number 1Nickolay ZosimovychThis publication suggests how we can improve the spacecraft centre of mass movement stabilization accuracy in the active phases of trajectory correction. It will be during interplanetary and transfer flights, which in some cases provides for high navigation accuracy, when rigid trajectory control method is used. The required stability conditions obtained are consistent with the known criteria in the invariant theory. Computer modelling shows that in a partially invariant stabilization system reveals the significant advantages of such a system in terms of greater accuracy when compared to known stabilization systems.
Abstract: Publication year: 2019Source: International Journal of Aerospace Sciences, Volume 7, Number 1M. Moret, H. Moustapha, Patricia Phutthavong, F. GarnierThe use of Multidisciplinary Design Optimization (MDO) techniques at the preliminary design phase (PMDO) of a gas turbine engine allows investing more effort at the pre-detailed phase in order to prevent the selection of an unsatisfactory concept early in the design process. Considering the impact of the turbine tip clearance on an engine’s efficiency, an accurate tool to predict the tip gap is a mandatory step towards the implementation of a full PMDO system for the turbine design. Tip clearance calculation is a good candidate for PMDO technique implementation considering that it implies various analyses conducted on both the rotor and stator. As a second step to the development of such tip clearance calculator satisfying PMDO principles, the present work explores the automation feasibility of the whole analysis phase of a turbine shroud segment and housing assembly preliminary design process, and the potential increase in the accuracy of results and time savings. The proposed conceptual system integrates a thermal boundary condition automated calculator and interacts with a simplified air system generator and with several design tools based on parameterized CAD models. Great improvements were found when comparing this analysis method results with regular pre-detailed level tools, as they revealed to be closer to the one generated by the detailed design tools used as target. Moreover, this design process revealed to be faster than a common preliminary design phase while leading to a reduction of time spent at the detailed design phase. By requiring fewer user inputs, this system decreases the risk of human error while entirely leaving the important decisions to the designer.
Abstract: Publication year: 2018Source: International Journal of Aerospace Sciences, Volume 6, Number 1Timothy Sands, Danni Lu, Janhwa Chu, Baolin ChengUnder the assumption of indifferently statics stability attitude controller is designed for the warhead based on Lyapunov theory. And also, a pseudo-inverse steering law with null motions is used to generate the gimbal velocity commands for SGCMGs, according to the desired torque from the attitude controller. Comparing with the strategies with fins or thrusters, the ablation of the actuators can be prevented and the aerodynamic shape can be preserved in this one since SGCMGs are mounted inside the warhead directly. Comparing with the moving mass or flywheels, SGCMGs can output torque large enough to meet the need of large-scope attitude reorientation and stabilization for the warhead. Simulation results using a Pershing II ballistic missile with a certain warhead indicate that the control strategy with SGCMGs is feasible. This document provides a technical translation from Chinese to English of recent developments to improve the ability of the mobile penetration, Single Gimbal Control Moment Gyroscopes (SGCMG) are adopted instead of the control fins and vector thrusters to produce the torque for the attitude control of the re-entry warhead. In addition to the technical translation, the manuscript is set in the broader context of the literature.
Abstract: Publication year: 2017Source: International Journal of Aerospace Sciences, Volume 5, Number 1Nickolay ZosimovychThe publication suggests how to significantly improve the spacecraft centre of mass movement stabilization accuracy in the active phases of trajectory correction during interplanetary and transfer flights, which in some cases provides for high navigation accuracy, when rigid trajectory control method is used. The required stability conditions obtained are consistent with the known criteria in the invariant theory. Computer modelling shows that in a partially invariant stabilization system reveals the significant advantages of such a system in terms of greater accuracy when compared to known stabilization systems.
Abstract: Publication year: 2017Source: International Journal of Aerospace Sciences, Volume 5, Number 1Mohamed A. Fouad Kandil, Abdelrady Okasha ElnadyIn this research, CFD analysis of the two-dimensional subsonic flow over a GOE 387 airfoil at various angles of attack and operating at a Reynolds number of 3 x105 is presented. Pressure distribution, Pressure Coefficient (Cp), Moment Coefficient (Cm) Lift Coefficient (Cl), and Drag Coefficient (Cd) are determined. The geometry of the airfoil is created using ANSYS Design Modeler. CFD analysis is carried out using FLUENT 17.2 at various angles of attack from -5° to 20°. Pressure distributions over GOE-387 airfoil for different angles of attack are presented. Moment coefficients and pressure coefficients are plotted against the angle of attack. Cl-Cd graph is plotted.
Abstract: Publication year: 2016Source: International Journal of Aerospace Sciences, Volume 4, Number 1Masoud Arabbeiki ZefrehWind energy is a promising alternative to the depleting non-renewable sources. Airborne wind turbine can reach much higher altitudes and produce higher power due to high wind velocity and energy density than the conventional wind turbines. The focus of this paper is to design a shrouded airborne wind turbine, capable of generating 70 kW to propel a leisure boat with a capacity of 8-10 passengers. The Solidworks model has been analyzed numerically CFD, by StarCCM+ software. At this moment, The Unsteady Reynolds Averaged Navier Stokes Simulation (URANS) has been analyzed. Turbulence model has been selected, to study the physical properties of the flow, with emphasis on the performance of the turbine and the increase in air velocity at the throat. The analysis has been done using two ambient velocities. For the first time, at inlet velocity of 12 m/s, the velocity of air at the turbine has been recorded as 16 m/s. The power generated by the turbine is 61 kW. For the second time, at inlet velocity of 6m/s, the velocity of air at turbine increased to 10 m/s. The power generated by turbine is 25 kW.
Abstract: Publication year: 2016Source: International Journal of Aerospace Sciences, Volume 4, Number 1Ayesha KausarThis report investigates the possibility of improving the mechanical properties of triglycidyl para-amino phenol (TGAP) epoxy through dispersion of nanodiamond (ND) and montmorillonite-nanodiamond (MMT-ND) filler. The montmorillonite was first intercalated with octadecylamine followed by nanodiamond intercalation to form MMT-ND. Both the pristine nanodiamond as well as MMT-ND was employed as filler to form nanocomposite with triglycidyl para-amino phenol. In this case, diethyltoluene diamine was used as hardener. It was found that the presence of nanofiller steadily decreased the β-transition temperature of TGAP/ND and TGAP/MMT-ND systems. Atomic force micrographs have shown fine particle dispersion in nanocomposite. The effect of filler concentration on mechanical properties of epoxy resins was also analyzed. TGAP/ND 1-5 system showed increase in modulus from 1676 to 3074 MPa, while greater modulus increase was seen for TGAP/MMT-ND 1-5 system in the range of 2388-3408 MPa. The balanced properties justified the application of novel epoxy nanocomposites in aviation industry.
Abstract: Publication year: 2016Source: International Journal of Aerospace Sciences, Volume 4, Number 1S. Martínez-Aranda, A. L. García-González, L. Parras, J. F. Velázquez-Navarro, C. del PinoThis experimental work deals with the influence of the angle of attack (AoA) and the chord based Reynolds number (Rec) on the lift and drag coefficients for a low-aspect-ratio NACA0012 airfoil. In addition, we provide novel general correlations for the minimum drag coefficient together with the ratio between the maximum lift and the minimum drag coefficient for different Reynolds numbers and several aspect ratios, after comparing our experimental data with other research works. This information is very useful for future validation of numerical simulations. Furthermore, we observe that the change in the aerodynamic characteristics are linked to the variations in the linear slope of the lift coefficient as function of AoA for any aspect ratio, thus finding a critical Reynolds number Rec=105 at which the slope saturates its value and the maximum of the polar curve changes its upward trend.
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