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Particuology 2021年第1期19卷 116-125页

作者： Xin Su Chengxiu Wang Xingying Lan Huajian Pei Xiaoyang Mao Jinsen Gao State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China

The axial flow structure in a high-density CFB riser having a height of 18 m is investigated on the basis of pressure *** circulation rates reach 1400 kg/(m2 s)at superficial gas velocities of 5-9 m/s and the apparent solids holdup exceeds 0.2,indicating high-density operations have been *** apparent solids holdup increases with the solids circulation rate increasing and/or superficial gas velocity *** distributions of the apparent solids holdup have exponential shapes with denser regions at the bottom and more dilute regions in the upper *** apparent slip velocity increases with the increasing solids holdup and reaches 14 m/s,showing that there are more opportunities of cluster formation in high-density ***,the apparent slip velocity has a power relation with the apparent solids holdup under a wide range of operating conditions.

关键词： Circulating fluidized bed pressure measurement Flow structure Solids holdup Slip velocity

Investigation of pressure wave behaviors in the rotational speed effects on a pressure-exchange wave rotor

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Chinese Journal of Aeronautics 2022年第5期35卷 247-259页

作者： Shining CHAN Huoxing LIU Hang SONG Fengchao LI Chongwen JIANG Zhenxun GAO Aircraft&Propulsion Laboratory Ningbo Institute of TechnologyBeihang UniversityNingbo 315800China National Laboratory for Computational Fluid Dynamics School of Aeronautic Science and EngineeringBeihang UniversityBeijing 100083China Research Institute of Aero-Engine Beihang UniversityBeijing 100083China AVIC CAPDI Integration Equipment Co. Ltd.Beijing 102206China Aero Engine Academy of China Beijing 101300China

A wave rotor is suitable for compact and efficient pressure-exchange between gas *** work measured the circumferential pressure distribution of the rotor/stator interfaces and utilized a CFD method to simulate the unsteady pressure *** experimental and CFD results showed some slopes in the circumferential pressure distributions,and the slopes indicated the traces of specific unsteady pressure *** traces varied regularly if the rotational speed varied within a range from-11%to+11%off the baseline value,but they were seriously disturbed if the rotational speed varied by-45%from the baseline *** verified that a pressure wave in a wave rotor tended to keep its pressure ratio and propagation velocity unchanged if the rotational speed varied by a small extent,and that the pressure wave could not keep its propagation patterns if the rotational speed varied by a large *** of the pressure wave behaviors,the wave rotor demonstrated specific regulations of the rotational speed effects on its operational states.

关键词： Experimental test pressure exchange pressure measurement Rotational speed Unsteady pressure wave Wave rotor

应用压力敏感涂料测量孤立叶片吸力面压力(英文)

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Chinese Journal of Aeronautics 2009年第2期22卷 138-144页

作者：周强刘波高丽敏陈柳生史淼西北工业大学动力与能源学院

Global pressure distribution on the suction surface of a single vane in a transonic cascade wind tunnel is measured with the help of intensity-based pressure-sensitive paint (PSP) technique using a type of temperature-insensitive fluorescent paint and a self-made measurement system. This measurement is conducted at the outlet of the cascade wind tunnel at the Mach numbers 0.3 and 0.4, attack angle about –20°, ambient pressure 95.4 kPa and temperature 15 °C. The vane under study owns a large camber angle of ...

关键词： turbomachinery pressure measurement pressure-sensitive paint pressure distribution cascade wind tunnel suction surface of vane image registration

Experimental investigation of characteristics of instability evolution in a centrifugal compressor

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Chinese Journal of Aeronautics 2023年第4期36卷 174-189页

作者： Hanzhi ZHANG Ce YANG Ben ZHAO Wei ZHAO Chenxing HU Wenli WANG Jianbing GAO Shijun SUN School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

The stable range of operation for the centrifugal compressor significantly influences the dynamic,economic,and environment-friendly characteristics of power systems.A deep understand-ing of the characteristics of instability evolution is necessary to improve the compressor stability.A centrifugal compressor equipped with a vaneless diffuser is experimentally investigated using high-response static-pressure *** results obtained indicate that three typical rotational-speed ranges exist based on the different instability evolution characteristics,which reveals the var-ious impeller–diffuser matching behaviors over the entire speed *** low-speed ranges((40%–75%)N_(max),N_(max)is the maximum rotational speed),the compressor exhibits stable,Rotating Insta-bility(RI),impeller stall(diffuser stall),and surge *** impeller stall mode is induced by RI and propagates downstream,resulting in the diffuser stall and compressor surge *** the medium-speed range((75%–85%)N_(max)),the compressor exhibits stable,diffuser stall,RI,and surge *** the high-speed range((85%–100%)N_(max)),the compressor exhibits stable,diffuser stall,and surge *** dominant instability position is shifted from the impeller to the diffuser as the rotational speed *** the impeller and diffuser stall present an irregular sawtooth static-pressure wave and exhibit broadband frequency spectrum patterns.

关键词： Centrifugal compressor Impellers pressure measurement Rotating instability Stability Stall

Experimental investigation of expansion effect on shock wave boundary layer interaction near a compression ramp

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Chinese Journal of Aeronautics 2022年第12期35卷 89-101页

作者： Junjie HUO Shihe YI Wenpeng ZHENG Haibo NIU Xiaoge LU Dundian GANG College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

The experiment is conducted to investigate the effect of expansion on the shock wave boundary layer interaction near a compression ramp. The small-angle expansion with an angle degree of 5° occurs at different positions in front of the compression ramp. The particle image velocimetry and flow visualization technology show the flow structures, velocity field, and velocity fluctuation near the compression ramp. The mean pressure distribution, pressure fluctuation, and power spectral density are measured by high-frequency response pressure transducers. The experimental results indicate that the expansion before the compression ramp position affects the shock wave boundary layer interaction to induce a large-scale separation. But the velocity fluctuation and pressure fluctuation are attenuated near the large-scale flow separation region. When the expansion occurs closer to the compression ramp, the expansion has a more significant impact on the flow. The fluctuation of velocity and pressure is significantly attenuated, and the wall pressure rise of the separation point is reduced obviously. And the characteristic low-frequency spectrum signal related to the unsteadiness of the shock wave boundary layer interaction is significantly suppressed. In addition, variation of the separation region scale at different compression angle degrees is distinctive with the effect of expansion.

关键词： Boundary layers Flow visualization Fluid dynamic pressure measurement Shock waves Supersonic aerodynamics Velocity measurement

ANSYS-Based Birefringence Property Analysis of Side-Hole Fiber Induced by pressure and Temperature

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Photonic Sensors 2018年第1期8卷 13-21页

作者： Xinbang ZHOU Zhenfeng GONG School of Ocean Science and Technology Dalian University of Technology. Panjin Panjin 124000 China College of Physics and Optoelectronics Engineering Dalian University of Technology Dalian 116024 China

In this paper, we theoretically investigate the influences of pressure and temperature on the birefringence property of side-hole fibers with different shapes of holes using the finite element analysis method. A physical mechanism of the birefringence of the side-hole fiber is discussed with the presence of different external pressures and temperatures. The strain field distribution and birefringence values of circular-core, rectangular-core, and triangular-core side-hole fibers are presented. Our analysis shows the triangular-core side-hole fiber has low temperature sensitivity which weakens the cross sensitivity of temperature and strain. Additionally, an optimized structure design of the side-hole fiber is presented which can be used for the sensing application.

关键词： Fiber optics birefringence pressure measurement temperature

Experimental investigation on static/dynamic characteristics of a fast-response pressure sensitive paint

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Chinese Journal of Aeronautics 2018年第6期31卷 1198-1205页

作者： Ruiyu LI Limin GAO Tianlong ZHENG Guanhua YANG School of Power and Energy Northwestern Polytechnical University Xi'an 710072 China Collaborative Innovation Center of Advanced Aero-Engine Beijing 100083 China

An optical-based technique using pressure-Sensitive Paint（PSP） is a promising method to measure the distribution of surface pressure on an aerodynamic model. The static and dynamic characteristics of a fast-response PSP that is developed in the Chinese Academy of Sciences（CAS）are analyzed and tested to serve as the basis for experiments on unsteady surface measurement using a fast-response PSP. Two calibration systems used for this study are set up to investigate the temperature dependency, response time, and resolution. A data processing method, used for dynamic data, is analyzed and selected carefully to determine the optimum signal. Results show that the fastresponse PSP can be used normally at temperatures from 25 ℃ to 80 ℃. The effect of temperature on the accuracy of the measurement must be considered when temperatures are beyond the temperature range of 30–40 ℃. The dynamic calibration device with a solenoid valve can achieve a pressure jump within a millisecond order. The resolution is determined by the signal-to-noise ratio of the photo-multiplier tube. Results of the measurement show that the response time of the PSP decreases with a large pressure variation, and the response time is below 0.016 s when the pressure variation is under 40 kPa.

关键词： Dynamic calibration pressure measurement pressure sensitive paint Signal processing Unsteady flow

COORELATION ANALYSIS OF SURFACE pressure FLUCTUATIONS ON THREE EQUISPACED CYLINDERS

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Journal of Hydrodynamics 2001年第2期13卷 55-62页

作者： Dong, L.Y. Xu, Y.H. Huang, D.Q. Inst. of Appl. Math. and Mech. Shanghai Univ. Shanghai 200072 China

The fluctuating pressures on the surface of three circular cylinders in equispaced arrangement were measured simultaneously in the medium subcritical regime (Re=3×104). The distributions of their rms values and circumferential correlation were obtained in the spacing range from 1.25 to 6.0. The spatial correlation of pressures of two pressure taps on two different cylinders at the same azimuth was investigated as well. Owing to different flow patterns in various arrangements and spacing, these correlation curves of pressure show different distributions. The lift fluctuation can be estimated qualitatively from the circumferential coefficient curve with the knowledge of the rms pressure distribution. Some critical spacing for each arrangement were found that the flow regimes and the corresponding pressure correlation take a sudden change. Flow interference between cylinders in each arrangement was also discussed with various flow regimes.

关键词： Cylinders (shapes) Experiments Flow interactions Flow patterns pressure distribution pressure measurement

CHARACTERISTICS OF CORRELATION AND SPECTRUM BETWEEN WALL FLUCTUATING pressure AND FLUCTUATING VELOCITY OF IMPINGING JET

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Journal of Hydrodynamics 2002年第3期14卷 21-28页

作者： Dai, Guang-Qing Yang, Yong-Quan Yang, Qing Wang, Hai-Yun Hydraulics Lab. of High Speed Flows Sichuan Univ. Chengdu 610065 China

The correlation, between wall fluctuating pressure and fluctuating velocity, on the bed of plunging pool under the action of single and twin impinging jet, and their spectrum and turbulent scale are investigated in the paper by using 2-D LDA and the dynamic pressure scanning system of multiple points. It is found that the cross correlation between the horizontal fluctuating velocity and the fluctuating pressure of twin jet is bigger than that of single jet, and the spectrums of horizontal fluctuating velocity and fluctuating pressure obviously have approximately same dominant frequency. The relationship between the fluctuation pressure coefficient on wall and the turbulent intensity near the wall can be described with logarithmic curve.

关键词： Hydraulic structures pressure pressure measurement Turbulence Velocity