scholarly journals Design of Ring-Focus Elliptical Beam Reflector Antenna

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Jun-Mo Wu ◽  
Xue Lei ◽  
Dong-fang Zhou ◽  
Lei Hou ◽  
Hong-wei Chen
Keyword(s):  
Design Process ◽  
Design Method ◽  
Beam Width ◽  
Transition Function ◽  
Reflector Antenna ◽  
New Method ◽  
Center Frequency ◽  
Basic Principles ◽  
Aperture Efficiency ◽  
Practical Engineering

A new method for the design of elliptical beam reflector antenna is presented in this paper. By means of the basic principles of ring-focus antenna, a circularly symmetric feed and two specially shaped reflectors are used to form an elliptical beam antenna. Firstly, the design process of this ring-focus elliptical beam antenna is studied in detail. Transition function is defined and used in the design process. Then, combining the needs of practical engineering, a ring-focus elliptical beam reflector antenna is manufactured and tested. The gain at center frequency (12 GHz) is 37.7 dBi with an aperture efficiency of 74.6%. 3 dB beam-width inφ=0°andφ=90°plane is2.6°and1.4°, respectively. Ratio of the elliptical beam (ratio of 3 dB beam-width inφ=0°andφ=90°plane) is2.6/1.4=1.85, substantially equal to designed ratio 2. Simulating and testing results match well, which testify the effectiveness of this design method.

scholarly journals Modernisation of LEMACH 6 Design-Research Method as a Reliability Engineering Tool

2020 ◽  
Vol 50 (2) ◽  
pp. 145-164
Author(s):  
Łucja Maria Kuraś ◽  
Maksymilian Smolnik
Keyword(s):  
Detailed Analysis ◽  
Design Process ◽  
Research Method ◽  
Design Research ◽  
Design Method ◽  
New Method ◽  
Reliability Testing ◽  
Reliability Engineering ◽  
Iterative Design ◽  
Mechanical Objects

AbstractThe article presents the developed design-research method for mechanical objects, which is a modernisation of the sequential-iterative design method LEMACH 6. As part of the design process organised by method guidelines, a number of activities related to designed object’s reliability testing and engineering were included. The article charac-terises selected design methods, with particular emphasis on the LEMACH 6 method. Next, assumptions were made regarding the development and use of the proposed solution, and a diagram and detailed analysis of individual elements of the new method were presented. The developed method enables the organisation of design works, allowing one to rapidly create new solutions and avoid mistakes during designing.

Development of the design method for the optimal design of the Neutron Converter experimental plant

2020 ◽  
Author(s):  
Timur Smetani ◽  
Elizaveta Gureva ◽  
Vyacheslav Andreev ◽  
Natalya Tarasova ◽  
Nikolai Andree
Keyword(s):  
Optimal Design ◽  
Flux Density ◽  
Design Process ◽  
Design Method ◽  
Fast Neutrons ◽  
Experimental Plant ◽  
Plant Design ◽  
State Technical ◽  
Research Organizations ◽  
Neutron Converter

The article discusses methods for optimizing the design of the Neutron Converter research plant design with parameters that are most suitable for a particular consumer. 38 similar plant structures with different materials and sources were calculated, on the basis of which the most optimal options were found. As part of the interaction between OKBM Afrikantov JSC and the Nizhny Novgorod State Technical University named after R. E. Alekseev, the Neutron Converter research plant was designed and assembled. The universal neutron converter is a device for converting a stream of fast neutrons emitted by isotopic sources into a "standardized" value of flux density with known parameters in the volume of the central part of the product, which is the working part of the universal neutron converter. To supply neutron converters to other customer organizations (universities, research organizations and collective centers), it is necessary to take into account the experience of operating an existing facility, as well as rationalize the design process of each specific instance in accordance with the requirements of the customer.

Design and Research of Double-Drum Winch with Anti-Pressure Wheel

2012 ◽  
Vol 479-481 ◽  
pp. 1709-1713
Author(s):  
Kai An Yu ◽  
Tao Yang ◽  
Chang Zhi Gong
Keyword(s):  
Finite Element ◽  
Bearing Capacity ◽  
Finite Element Methods ◽  
Design Method ◽  
New Method

In view of the problems of large stress and severe bearing heating in double-drum winch at present, this paper adopted a new method to enhance bearing capacity for double-drum winch by adding anti-pressure wheels between two drums. Finite element methods were used to analyze the strength of 4000kN-traction double-drum winches with anti-pressure wheels and without anti-pressure wheels respectively. The results of the analysis revealed that the stress of the cylinder bearing decreased from 264MPa to 167MPa. The new method by adding anti-pressure wheels had remarkably improved the endurance of the bearing. Therefore, the design method can be widely used in large-traction double-drum winch.

scholarly journals Design of Wideband Bandpass Filter Based on Corrugated Disk Resonator with Multiple Resonant Modes

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2614
Author(s):  
Qian Yang ◽  
Shuangyang Liu ◽  
Hongyu Shi ◽  
Kai-Da Xu ◽  
Xinyue Dai ◽  
...  
Keyword(s):  
Theoretical Analysis ◽  
Bandpass Filter ◽  
Design Method ◽  
Center Frequency ◽  
Localized Surface Plasmons ◽  
Metallic Structure ◽  
Disk Resonator ◽  
Resonant Frequencies ◽  
Resonant Modes ◽  
Via Holes

A corrugated disk resonator with eight grooves is proposed for wideband bandpass filter (BPF) design. Due to the spoof localized surface plasmons resonances of the corrugated metallic structure, the dipole, quadrupole, hexapole modes, and a fundamental mode excited by the introduced short-circuited via holes are employed to realize four transmission poles (TPs) in the passband. The theoretical analysis is described by the electric field and current distributions on the resonator. The resonant frequencies can be tuned easily by the parameters of the structure, which can be used to adjust the center frequency and bandwidth of the BPF freely. Furthermore, two resonators are cascaded to obtain eight TPs to improve the selectivity performance. Finally, three fabricated filters demonstrate the design method.

scholarly journals Development of Optimal Design Method for Steel Double-Beam Floor System Considering Rotational Constraints

2021 ◽  
Vol 11 (7) ◽  
pp. 3266
Author(s):  
Insub Choi ◽  
Dongwon Kim ◽  
Junhee Kim
Keyword(s):  
Optimal Design ◽  
Design Process ◽  
Design Method ◽  
Steel Beams ◽  
High Gravity ◽  
Double Beam ◽  
Iterative Analysis ◽  
Floor Systems ◽  
Optimal Design Method ◽  
Floor System

Under high gravity loads, steel double-beam floor systems need to be reinforced by beam-end concrete panels to reduce the material quantity since rotational constraints from the concrete panel can decrease the moment demand by inducing a negative moment at the ends of the beams. However, the optimal design process for the material quantity of steel beams requires a time-consuming iterative analysis for the entire floor system while especially keeping in consideration the rotational constraints in composite connections between the concrete panel and steel beams. This study aimed to develop an optimal design method with the LM (Length-Moment) index for the steel double-beam floor system to minimize material quantity without the iterative design process. The LM index is an indicator that can select a minimum cross-section of the steel beams in consideration of the flexural strength by lateral-torsional buckling. To verify the proposed design method, the material quantities between the proposed and code-based design methods were compared at various gravity loads. The proposed design method successfully optimized the material quantity of the steel double-beam floor systems without the iterative analysis by simply choosing the LM index of the steel beams that can minimize objective function while satisfying the safety-related constraint conditions. In particular, under the high gravity loads, the proposed design method was superb at providing a quantity-optimized design option. Thus, the proposed optimal design method can be an alternative for designing the steel double-beam floor system.

Impact of Secondary Flow on the Accuracy of Simplified Design Methods for Steam Turbine Stages

2012 ◽  
Author(s):  
Jan Schumann ◽  
Ulrich Harbecke ◽  
Daniel Sahnen ◽  
Thomas Polklas ◽  
Peter Jeschke ◽  
...  
Keyword(s):  
Secondary Flow ◽  
Steam Turbine ◽  
Design Process ◽  
Design Method ◽  
Computing Time ◽  
Leading Edge ◽  
Design Methods ◽  
Preliminary Design ◽  
Line Design ◽  
Radial Equilibrium

The subject of the presented paper is the validation of a design method for HP and IP steam turbine stages. Common design processes have been operating with simplified design methods in order to quickly obtain feasible stage designs. Therefore, inaccuracies due to assumptions in the underlying methods have to be accepted. The focus of this work is to quantify the inaccuracy of a simplified design method compared to 3D Computational Fluid Dynamics (CFD) simulations. Short computing time is very convenient in preliminary design; therefore, common design methods work with a large degree of simplification. The origin of the presented analysis is a mean line design process, dealing with repeating stage conditions. Two features of the preliminary design are the stage efficiency, based on loss correlations, and the mechanical strength, obtained by using the beam theory. Due to these simplifications, only a few input parameters are necessary to define the primal stage geometry and hence, the optimal design can easily be found. In addition, by using an implemented law to take the radial equilibrium into account, the appropriate twist of the blading can be defined. However, in comparison to the real radial distribution of flow angles, this method implies inaccuracies, especially in regions of secondary flow. In these regions, twisted blades, developed by using the simplified radial equilibrium, will be exposed to a three-dimensional flow, which is not considered in the design process. The analyzed design cases show that discrepancies at the hub and shroud section do exist, but have minor effects. Even the shroud section, with its thinner leading-edge, is not vulnerable to these unanticipated flow angles.

scholarly journals Optimal Unimodular Sequences Design Method for Active Sensing Systems

2018 ◽  
Vol 2018 ◽  
pp. 1-13 ◽  
Author(s):  
Ze Li ◽  
Ping Li ◽  
Xinhong Hao ◽  
Xiaopeng Yan
Keyword(s):  
Optimization Problems ◽  
Design Method ◽  
Correlation Coefficients ◽  
Continuous Phase ◽  
Active Sensing ◽  
Sidelobe Level ◽  
One Dimensional ◽  
Sensing Systems ◽  
Practical Engineering ◽  
Dimensional Optimization

In active sensing systems, unimodular sequences with low autocorrelation sidelobes are widely adopted as modulation sequences to improve the distance resolution and antijamming performance. In this paper, in order to meet the requirements of specific practical engineering applications such as suppressing certain correlation coefficients and finite phase, we propose a new algorithm to design both continuous phase and finite phase unimodular sequences with a low periodic weighted integrated sidelobe level (WISL). With the help of the transformation matrix, such an algorithm decomposes the N-dimensional optimization problem into N one-dimensional optimization problems and then uses the iterative method to search the optimal solutions of the N one-dimensional optimization problems directly. Numerical experiments demonstrate the effectiveness and the convergence property of the proposed algorithm.

A New Design Method for the Fault Diagnosis on the Rotating Rectifier of Aeronautic Synchronous Generator

2012 ◽  
Vol 548 ◽  
pp. 544-547
Author(s):  
Yong Zhi Liu ◽  
Cong Liu
Keyword(s):  
Fault Diagnosis ◽  
Feature Vector ◽  
Design Method ◽  
Synchronous Generator ◽  
New Method ◽  
Test Analysis ◽  
Exciting Current ◽  
On Line

A new method of fault diagnosis on the rotating rectifier of aeronautic synchronous is raised in the work. Firstly, the condition, truth and approach of EMD are introduced, and the method and steps of building up the feature vector are also included, Secondly the theories of LS-SVM and the arithmetic in the classification are also included. Finally taking the faults of one and two diodes turning off for example, after extracting the feature vector of exciting current based on EMD and establishing the classifying method based on Gauss RBF LS-SVM, the test, analysis and comparison can be on between LS-SVM and NN the conclusion can be got that the classified method referred in the work owns higher exactness, takes less time and has more application on the on-line fault diagnosis NN.

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