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Underwater glider design based on dynamic model analysis and prototype development

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第8期14卷 583-599页

作者： Shuang-shuang FAN Can-jun YANG Shi-lin PENG Kai-hu LI Yu XIE Shao-yong ZHANG The State Key Lab of Fluid Power Transmission and Control Zhejiang University

Underwater gliders are efficient mobile sensor platforms that can be deployed for months at a time, traveling thousands of kilometers. Here, we describe our development of a coastal 200 m deep underwater glider, which can serve as an ocean observatory platform operating in the East China Sea. Our glider is developed based on dynamic model analysis: steady flight equilibrium analysis gives the varied range of moving mass location for pitch control and the varied vehicle volume for buoyancy control; a stability analysis is made to discuss the relationship between the stability of glider motion and the location of glider wings and rudder by root locus investigation of glider longitudinal- and lateral-directional dynamics, respectively. There is a tradeoff between glider motion stability and control authority according to the specific glider mission requirements. The theoretical analysis provides guidelines for vehicle design, based on which we present the development progress of the Zhejiang University (ZJU) glider. The mechanical, electrical, and software design of the glider is discussed in detail. The performances of glider key functional modules are validated by pressure tests individually; preliminary pool trials of the ZJU glider are also introduced, indicating that our glider functions well in water and can serve as a sensor platform for ocean sampling.

关键词： Underwater glider design Equilibrium Stability pressure test Pool trial

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Design of Linear Sweep Source Based on DDS Used in Readout System for Wireless Passive pressure Sensor

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Photonic Sensors 2014年第4期4卷 359-365页

作者： Yingping HONG Science and Technology on Electronic test & Measurement Laboratory North University of China Taiyuan 030051China Key Laboratory Instrumentation Science & Dynamic Measurement Ministry of Education North University of ChinaTaiyuan 030051 China

This paper proposes the design and research on the high bandwidth linear frequency sweep signal source involved in the readout unit module of the wireless passive pressure sensor in high temperature based on the principle of mutual inductance coupling which is applied widely at present. The operating principle of the linear sweep frequency source based on the direct digital frequency synthesis （DDS） technology is introduced, and the implementation method of the hardware circuit and logic sequential control process required in our system has been realized utilizing this technology. Through the experiments under different conditions of the step value, the sweep range and other related design indicators, the influence on the extraction method of resonance frequency information, extraction accuracy, and others during the readout system of the mutual inductance coupling sensor are analyzed and studied. The design of the linear frequency sweep signal source is realized with a resonance frequency change resolution of 6 kHz, a minimum step value of 1 kHz, and a precision of frequency for 0.116 Hz within the sweep width of 1 MHz - 100MHz. Due to the use of the integrated commercial chip, the linear sweep frequency source is made small in size, high working frequency, high resolution and low step values for the readout unit modularized of a higher application value.

关键词： Direct digital frequency synthesizer LC resonant sensor resonant frequency pressure test

Theoretical and Applied Mechanics Letters

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Theoretical & Applied Mechanics Letters 2021年第2期11卷 63-69页

作者： Xuan Zhao Lin Du Xuhao Peng Zichen Deng Weiwei Zhang College of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China National Key Laboratory Science and Technology on Aerodynamic Design and Research Northwestern Polytechnical UniversityXi’an 710072China School of Mathematics and Statistics Northwestern Polytechnical UniversityXi’an 710129China MIITKey Laboratory of Dynamics and Control of Complex Systems Northwestern Polytechnical UniversityXi’an 710072China School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an 710129China

The placement of pressure taps on the surface of the wind tunnel test model is an important means toobtain the surface pressure ***,limited by space location and experimental cost,it isdifficult to arrange enough pressure measuring taps on the surface of complex models to obtain completepressure distribution information,thus it is impossible to obtain accurate lift and moment characteristicsthrough *** paper proposes a refined reconstruction method of airfoil surface pressure basedon compressed sensing,which can reconstruct the pressure distribution with high precision with lesspressure measurement *** on typical airfoil subsonic flow around flow show that the accuracyof lift and moment after the pressure integration reconstructed by 4-8 measuring points can meet therequirements of the national military *** algorithm is robust to noise,and provides a new ideafor obtaining accurate force data from sparse surface pressure tests in engineering.

关键词： pressure test Compressed sensing Proper orthogonal decomposition pressure field reconstruction

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Design of deep-water omnidirectional spirit level

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Journal of Measurement Science and Instrumentation 2021年第4期12卷 472-478页

作者： ZHAO Lianyu LI Shuo ZHAO Xiaolei LI Maolin CHEN Jinyu WANG Chenglin Tianjin Key Laboratory of Advanced Mechatronic System Design and Intelligent Control National Demonstration Center of Experimental Mechanical and Electrical Engineering EducationSchool of Mechanical EngineeringTianjin University of TechnologyTianjin 300384China Offshore Oil Engineering Co. Ltd.Tianjin 300461China

Attitude adjustment is a key link in the installation process of underwater facilities in deep *** solve this problem,an omnidirectional spirit level for deep water was *** sealing principle of the spirit level and the principle of deep-water pressure resistance are analyzed,and the threaded connection strength is *** mechanical simulation verifies that the spirit level can withstand the pressure of 2000 m water depth,and the water pressure test is carried out for 30 min in a 20 MPa hyperbaric *** the experiment is completed,the appearance of the spirit level is intact and there is no *** experiment results show that the deep-water omnidirectional spirit level can be used in the deep sea within 2000 m.

关键词： deep water omnidirectional spirit level attitude adjustment pressure test underwater pressure

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New method of calculating formation parameters of low permeability gas reservoir

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Journal of Energy and Power Engineering 2009年第3期2卷 34-39页

作者： SHANG Xi-tao HE Shun-li LI Xiu-sheng MOE Key Laboratory of Petroleum Engineering China University of Petroleum Beijing 102249 China

The data of modified isochronal testing of gas well is just used to calculate gas well deliverability. Fully utilizing well test data make it possible to obtain formation parameters, such as gas well deliverability, effective permeability and skin factor at the same time. Based on transient flow theory, the pressure drawdown equation of gas unsteady seepage can be deducted. One simulated case is used to illustrate the applicability of the proposed method. The result of analyzed case shows that the proposed method can provide accurate estimate of formation permeability and skin factor compared with the method of Homer curves.

关键词： gas reservoir well testing pressure test formation parameters method