scholarly journals High-speed range and velocity measurement using frequency scanning interferometry with adaptive delay lines [Invited]

2020 ◽  
Vol 37 (11) ◽  
pp. 1814
Author(s):  
Christos A. Pallikarakis ◽  
Jonathan M. Huntley ◽  
Pablo D. Ruiz
Keyword(s):  
Velocity Measurement ◽  
High Speed ◽  
Delay Lines ◽  
Frequency Scanning ◽  
Speed Range ◽  
Frequency Scanning Interferometry

scholarly journals High-enthalpy hypersonic flows

2020 ◽  
Vol 2 (1) ◽  
Author(s):  
Joseph J. S. Shang ◽  
Hong Yan
Keyword(s):  
Hypersonic Flow ◽  
High Speed ◽  
Quantum Physics ◽  
Nonequilibrium Thermodynamic ◽  
Strong Shock ◽  
Hypersonic Flows ◽  
Electrically Conducting ◽  
High Enthalpy ◽  
Speed Range ◽  
Flow Theories

Abstract Nearly all illuminating classic hypersonic flow theories address aerodynamic phenomena as a perfect gas in the high-speed range and at the upper limit of continuum gas domain. The hypersonic flow is quantitatively defined by the Mach number independent principle, which is derived from the asymptotes of the Rankine-Hugoniot relationship. However, most hypersonic flows encounter strong shock-wave compressions resulting in a high enthalpy gas environment that always associates with nonequilibrium thermodynamic and quantum chemical-physics phenomena. Under this circumstance, the theoretic linkage between the microscopic particle dynamics and macroscopic thermodynamics properties of gas is lost. When the air mixture is ionized to become an electrically conducting medium, the governing physics now ventures into the regimes of quantum physics and electromagnetics. Therefore, the hypersonic flows are no longer a pure aerodynamics subject but a multidisciplinary science. In order to better understand the realistic hypersonic flows, all pertaining disciplines such as the nonequilibrium chemical kinetics, quantum physics, radiative heat transfer, and electromagnetics need to bring forth.

scholarly journals An efficient method for the compensation of dispersion mismatch in the frequency-scanning interferometry

2021 ◽  
Author(s):  
Qiang Zhou ◽  
Tengfei Wu ◽  
Yang Liu ◽  
yue shang ◽  
Jiarui Lin ◽  
...  
Keyword(s):  
Efficient Method ◽  
Frequency Scanning ◽  
Frequency Scanning Interferometry

Torque imporvement of IPM motors with skewing magnetic designs

2021 ◽  
pp. 3-10
Author(s):  
Dinh Hai Linh
Keyword(s):  
Permanent Magnet ◽  
High Speed ◽  
Torque Ripple ◽  
Maintenance Cost ◽  
Permanent Magnet Motor ◽  
Element Analysis ◽  
Speed Range ◽  
Interior Permanent Magnet ◽  
Interior Permanent Magnet Motor ◽  
Wide Speed Range

In this paper, a type interior permanent magnet synchronous motor designs is proposed for sport scooter application to improve constant torque wide speed performance. Interior Permanent Magnet machines are widely used in automotive applications for their wide-speed range operation and low maintenance cost. An existing permanent magnet motor (commercial QS Motor) is 3 kW-3000 rpm. In order to improve torque and power in wide speed range, a IPM electric motor 5.5 kW -5000 rpm can run up to 100 km/h: An Step-Skewing Interior Permanent Magnet motor alternatives is designed and optimized in detail with optimal magnetic segment V shape. The electromagnetic charateristics of Interior Permanent Magnet motors with V shape are compared with the reference Surface Permanent Magnet motor for the same geometry parameter requirements. Detailed loss and efficiency result is also analyzed at rate and maximum speeds. A prototype motor is manufactured, and initial experimental tests are performed. Detailed comparison between Finite Element Analysis and test data are also presented. It is shown that it is possible to have an optimized Interior Permanent Magnet motor for such high-speed traction application. This paper will figure out optimal angle of magnetic V shape for maximum torque and minimum torque ripple.

Photonic Doppler velocimetry used for instant velocity measurement of high-speed small flyer

2016 ◽  
Vol 45 (12) ◽  
pp. 1217001 ◽  
Author(s):  
吴立志 Wu Lizhi ◽  
陈少杰 Chen Shaojie ◽  
叶迎华 Ye Yinghua ◽  
沈瑞琪 Shen Ruiqi ◽  
刘卫 Liu Wei
Keyword(s):  
Velocity Measurement ◽  
High Speed ◽  
Doppler Velocimetry ◽  
Photonic Doppler Velocimetry

scholarly journals Vibration Compensation of the Frequency-Scanning-Interferometry-Based Absolute Ranging System

2019 ◽  
Vol 9 (1) ◽  
pp. 147 ◽  
Author(s):  
Fu-Min Zhang ◽  
Ya-Ting Li ◽  
Hao Pan ◽  
Chun-Zhao Shi ◽  
Xing-Hua Qu
Keyword(s):  
Standard Deviation ◽  
Vibration Frequency ◽  
Phase Modulation ◽  
Vibration Velocity ◽  
Sinusoidal Vibration ◽  
Vibration Effect ◽  
Frequency Scanning ◽  
Blind Area ◽  
Frequency Scanning Interferometry ◽  
Vibration Compensation

The frequency-scanning-interferometry-based (FSI-based) absolute ranging technology is a type of ranging technology possessing a high precision and no ranging blind area, so it can be used for non-cooperative targets. However, due to a tiny movement of a target, the Doppler shift and the phase modulation are introduced into the beat signal which results in ranging accuracy decrease. In order to solve this problem, first the model of vibration effect is established, and then the beat signals of two adjacent scanning periods are processed to produce a signal that is immune to vibration. The proposed method is verified by the experiments, and the experimental results show that the effect of vibration compensation is better for the target with a lower vibration velocity and at a lower vibration frequency (lower than 6 Hz). When the target is subjected to a sinusoidal vibration with an amplitude of 10 μm at a frequency of 1 Hz, by using the proposed method the standard deviation is reduced from 775 to 12 μm. Moreover, in the natural environment, by using vibration compensation the standard deviation is reduced from 289 to 11 μm.

scholarly journals Dual-Pulse Mode Control of a High-Speed Doubly Salient Electromagnetic Machine for Loss Reduction and Speed Range Extension

2020 ◽  
Vol 67 (6) ◽  
pp. 4391-4401
Author(s):  
Li Yu ◽  
Zhuoran Zhang ◽  
Zhangming Bian ◽  
David Gerada ◽  
Chris Gerada
Keyword(s):  
High Speed ◽  
Pulse Mode ◽  
Range Extension ◽  
Loss Reduction ◽  
Mode Control ◽  
Doubly Salient ◽  
Speed Range
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