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This paper constructed a new high speed and power density servo motor design scheme based on magnetic pole eccentricity proposed according to the requirements of electrical performance parameters. The analytical formulae were deduced in view of the theory of thick-walled elastic cylinders and the actual model by analytical calculations and finite element calculations. The structure strength of permanent magnet was analyzed. Furthermore, comprehensively comparing and analyzing the calculation results of the two methods verify the accuracy of the analytical calculation method and the rationality of the permanent magnet structure design. In brief, this paper provides a reference for the design of high-speed motor magnetic pole eccentricity.

Spherical Tokamak (ST) path to Fusion has been proposed [1] and experiments on STs demonstrated feasibility of this approach. Advances in High Temperature Superconductor technology [2] allows significant increase in the toroidal field (TF) which was found to improve confinement in STs. The combination of the high normalised plasma pressure, β, which has been achieved in STs [3], and high TF that can be produced by HTS TF magnets, opens a path to lower-volume fusion reactors, in accordance with the fusion power scaling proportional to β2Bt4V. Modular approach then becomes an alternative to high power, GW-scale Fusion reactors [4,5]. Feasibility of low-power compact ST reactor module and physics and engineering challenges of the accelerated, ST path to Fusion Power are discussed in this paper, on example of the first our prototype on this route, high-field compact spherical tokamak ST40.Spherical Tokamak (ST) path to Fusion has been proposed [1] and experiments on STs demonstrated feasibility of this approach. Advances in High Temperature Superconductor technology [2] allows significant increase in the toroidal field (TF) which was found to improve confinement in STs. The combination of the high normalised plasma pressure, β, which has been achieved in STs [3], and high TF that can be produced by HTS TF magnets, opens a path to lower-volume fusion reactors, in accordance with the fusion power scaling proportional to β2Bt4V. Modular approach then becomes an alternative to high power, GW-scale Fusion reactors [4,5]. Feasibility of low-power compact ST reactor module and physics and engineering challenges of the accelerated, ST path to Fusion Power are discussed in this paper, on example of the first our prototype on this route, high-field compact spherical tokamak ST40.

This paper presents a mathematical model and code-implemented engineering calculation technique that allow to study workflow inside a ramjet’s combustion chamber under dynamic variation of external and internal parameters: flight speed, angle of attack, and fuel mass flow rate. To assess adequacy of the mathematical model and the technique, a comparison is performed between results of internal ballistics calculations of a spaceplane’s ramjet obtained by aforementioned mathematical model and by numerical simulation in a computational fluid dynamics software package. This is tested for cruise flight conditions and for dynamic variation of flight parameters and fuel mass flow rate in a wide range. It shows that for a model subsonic flow combustion chamber a satisfactory correlation between these solutions is realized. Transient processes are stable and monotonous for all cases studied, registered oscillations of total pressure and temperature in relation to their stabilized values and weak overshooting have no effect on the engine’s output characteristics.

This paper aims to design a small-scale, compact supersonic wind tunnel nozzle using the method of characteristics and perform computational fluid dynamics (CFD) simulations to validate the design. The wind tunnel is designed to have a test section of 7cm × 7cm and a test section Mach number of 2.0. Simulations were performed for both 3D inviscid and viscous cases and it shows that for both cases, the obtained Mach number conforms with the design requirements. A further study on the effects of different pressure ratios, towards the position of shock waves, shows that an increase in the ratio would result the shock waves to shift downstream.

Malaysia Youth Satellite (MYSat) is a scientific 1U CubeSat initiated by School of Aerospace Engineering Universiti Sains Malaysia (USM) in 2016. The objective of the MYSat mission is to measure accurate electron density and temperature in E-layer of the ionosphere by a CubeSat. This mission was driven from a study which reported that Earthquake precursors could be analyzed from the ionosphere. Electron temperature and density probe (TeNeP) was the selected scientific instrument for MYSat. This instrument develops a technique by measuring the shift of electric floating potential (ΔVf) characteristics of an electrode immersed in plasma. The ΔVf characteristic of the plasma will then be retrieved from the instrument where the plasma’s electron density (ne) together with the temperature (Te) can be acquired. The TeNeP instrument has been proven not affected by the satellite potential variation effects, which is a common problem for electron measurements onboard small satellites, especially CubeSats. Therefore, the accurate Te and ne measured by MYSat could contribute to the on-going research regarding ionospheric physics and possible Earthquake precursor effects. An already developed TeNeP circuit based on a 2U platform has been redeveloped for MYSat’s 1U based platform. In this paper, several performance tests to the TeNeP generator circuit in the preparation of the MYSat will be shown and discussed.

In this paper, we propose Two Dimensional Photonic Crystal (2DPC) square lattice structure to design Channel Drop Filter (CDF) for optical communication networks. The proposed filter is designed using dual curved Photonic Crystal Ring Resonator (PCRR). The Photonic Band Gap (PBG) is calculated by Plane Wave Expansion (PWE) method. The 2DPC square lattice periodic arrays of dielectric rods have been investigated by Finite Difference Time Domain (FDTD) method. The number of rods in Z and X directions are 21 and 20, respectively with lattice constant a = 0.540 µm and rod radius r = 0.1 µm. The Filter has been optimized for telecommunication wavelengths λ = 1.551 µm with refractive indices 3.31 of materials Al0.4Ga0.6As. Further, the investigation is extended for study the effect of scattering rods radius, which leads to shift of resonant wavelength. The proposed structure is useful for CWDM optical communication systems and photonic integrated circuits which is ultra-compact device.

This paper discusses the quality of GPS antenna signals on the effect of rocket attitude using SDR (Software Defined Radio). The antenna is mounted on the surface of the rocket tube, where the rocket’s position is horizontal, vertical, and tilted. The quality of the GPS signal is determined by the number of satellites that can be detected and the received signal strength. The experimental results show that when the rocket is horizontal and the antenna is on the upper surface, the signal is strongest and the number of satellites detected is more than the other positions (>4 satellite). The signal is weakest when the rocket is horizontal and the antenna position is on the lower surface so that the number of satellites detected is least.

In this paper, mode generation based on an elliptical core few mode fiber (EC-FMF) is devised through an inverse function, designed using split step beam propagation method (BPM). The undesired modes from an EC-FMF are eliminated through an appended waveguide computed from the inverse phase of undesired modes. The EC-FMF may be used as an all-optical switch.

The temperature in the nose region of a hypersonic vehicle can be extremely high, for example, reaching approximately 11 000 K at a Mach number of 36 (Apollo reentry). The bow shock wave is normal, or nearly normal, in the nose region of a blunt body. Fortunately, the nose geometry is a spherical sector; therefore, hypersonic aerodynamics near the nose of space vehicle can be studied with a hypersonic axisymmetric CFD code for flows without incidence and this greatly decreases the computational effort. For this reason, the present paper deals with the development of a hypersonic axisymmetric CFD code.

Current research paper deals with the numerical analysis of an idealized fighter jet wing in a multi-module aero-thermal-structural environment during supersonic flights. At high Mach number, heat is generated due to the friction between the body and the fluid flow, which must be considered for structural analyses. Six different Mach numbers ranging from 1.25 to 2.5 are chosen to understand the effect of viscous heating on the wing model. Ansys CFD is coupled with thermal/structural module to calculate the numerical results. It is observed that for Mach number 1.75 and beyond, equivalent Von-mises stress due to pressure load is almost identical. However, with viscous heating consideration, equivalent stress values are increased with higher Mach number which magnifies the significance of thermal loading on the structure

Coflow-jet (CFJ) airfoil is a new type of zero-net mass flux active flow control of the airfoils. The concept was proposed by Zha et al from Miami University and presents several extraordinary aerodynamic characteristics like: super-lift coefficient, small or even negative drag coefficient and almost stall free behaviour. All these make the CFJ airfoils suitable for highly efficient airplanes including electric airplanes with distributed thrust. This paper presents an evaluation of the broadband aeroacoustic noise of a NACA 6415 CFJ airfoil and compares it with the basic NACA 6415. Numerical simulation for aerodynamic and aeroacoustic field using Navier –Stokes equations and aeroacoustic analogies are conducted with Ansys Fluent and Msc Actran solvers.