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EFFECT OF NON-SPHERICAL PARTICLES ON THE FLUID TURBULENCE IN A PARTICULATE pipe flow

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Journal of Hydrodynamics 2004年第6期16卷 721-729页

作者： SUNLei LINJian-zhong WUFa-li CHENYi-min DepartmentofMechanics StateKeyLaboratoryofFluidPowerTransmissionandControlZhejiangUniversityHangzhou310027China

In the non-spherical particulate turbulent flows, a set of new fluidfluctuating velocity equations with the non-spherical particle source term were derived, then a newmethod, which treats the slowly varying functions and rapidly varying functions separately, wasproposed to solve the equations, and finally the turbulent intensity and the Reynolds stress of theflu-id were obtained by calculating the fluctuating velocity statlsti-cally. The equations andmethod were used to a paniculate tur-bulent pipe flow. The results show that the turbulent intensityand the Reynolds stress are decreased almost inverse proportion-ally to the fluctuating velocityratio of particle to fluid. Non-spherical particles have a greater suppressing effect on thetur-bulence than the spherical particles. The particles with short re-laxation time reduce theturbulence intensity of fluid, while the particles with long relaxation time increase the turbulenceinten-sity of fluid. For fixed particle and fluid, the small particles sup-press the turbulence andthe large particles increase the turbu-ience.

关键词： paniculate flow non-spherical particle turbu-lent property pipe flow

RESEARCH ON THE MOTION OF PARTICLES IN THE TURBULENT pipe flow OF FIBER SUSPENSIONS

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Applied Mathematics and Mechanics(English Edition) 2004年第7期25卷 741-750页

作者：张卫峰林建忠 Department of Mechanics

The motion of fibers in turbulent pipe flow was simulated by 3-D integral method based on the slender body theory and simplified model of *** orientation distribution of fibers in the computational area for different Re numbers was *** results which were consistent with the experimental ones show that the fluctuation velocity of turbulence cause fibers to orient *** orientation distributions become broader as the Re number *** the fluctuation velocity and angular velocity of fibers were *** are affected by the fluctuation velocity of *** fluctuation velocity intensity of fiber is stronger at longitudinal than at lateral,while it was opposite for the fluctuation angular velocity intensity of ***,the spatial distribution of fiber was *** is obvious that the fiber dispersion is strenghened with the increase of Re numbers.

关键词： fiber suspension numerical simulation pipe flow turbulent orientation

K-ε-T MODEL OF DENSE LIQUID-SOLID TWO-PHASE TURBULENT flow AND ITS APPLICATION TO THE pipe flow

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Applied Mathematics and Mechanics(English Edition) 2000年第5期21卷 519-528页

作者：魏进家胡春波姜培正 1.802 Division Northwestern Polytechnical University Xi'an P R China Chemical Machinery and Equipment Department Xi'an Jiaotong University Xi'an P R China

To predict the characteristics of dense liquid-solid two-phase flow, K-Ε-T model is established, in which the turbulent flow of fluid phase was described with fluid turbulent kinetic energy Kf and its dissipation rate Εf, and the particles random motion was described with particle turbulent energy Kp and its dissipation rate Εp and pseudothermal temperature Tp. The governing equations were also derived. With K-Ε-T model, numerical study of dense liquid-solid two-phase turbulent up-flow in a pipe is performed. The calculated results are in good agreement with experimental data of Alajbegovic et al. (1994), and some flow features are captured.

关键词： Liquids Numerical analysis Particles (particulate matter) pipe flow Solids Turbulent flow

Research on the orientation distribution of fibers immersed in a pipe flow

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2002年第5期 2-7页

作者：林建忠张卫峰王叶龙 Department of Mechanics Zhejiang UniversityHangzhou 310027China

The computed orientation distribution of fibers immersed in laminar pipe flows showed that the longitudinal distributions are wide for small Reynolds numbers and become narrower with increasing Re . For low Re number, the axial orientation distributions are broad with almost no preferred orientations. For high Re number, the axial distribution becomes narrow, with sharp maxima. The mean values of the longitudinal orientation depend strongly on the Re number. The computed results are in qualitative agreement with relevant experimental results.

关键词： Fiber suspension Orientation distribution Computation pipe flow

ANALYTIC SOLUTIONS OF INCOMPRESSIBLE LAMINAR flow IN THE INLET REGION OF A pipe

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Applied Mathematics and Mechanics(English Edition) 2004年第8期25卷 894-897页

作者：孟庆国 Department of Mathematical and Physical Sciences National Natural Science Foundation of China Beijing 100085 P.R.China

The laminar analytic solutions of velocities and pressure in the central zone of the inlet region of pipe flow are given under the condition of uniform inflow, based on the Navier-Stokes equations of incompressible vi... 详细信息

关键词： pipe flow laminar flow inlet region analytic solution

Measurement of Fluid flow in pipe and Porous Media by High-Resolution Magnetic Resonance Imaging

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China Ocean Engineering 2012年第2期26卷 317-328页

作者：蒋兰兰宋永臣刘瑜豆斌林朱宁军赵佳飞 BULITI Abudul baKey Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education Dalian University ofTechnology North Japan New Energy Research Center Hirosaki University

The objective of this study is to understand the process of fluid flow in pipe and porous media with different pore structures. High-resolution Magnetic Resonance Imaging （MRI） technique was used to visualize the pore structure and measure fluid flow. The porous media was formed by packed bed of glass beads. flow measurement was carried out by a modified spin echo sequence. The results show that the velocity distribution in pipe is annular and the linear relation between MRI velocity and actual velocity is found in pipe flow measurement. The flow distribution in porous media is rather heterogeneous, and it is consistent with heterogeneous pore structure. The flow through pores with the high volume flow rate is determined largely by geometrical effects such as pore size and cross-sectional area.

关键词： MRI pore structure velocity distribution pipe flow porous media

THEORETICAL STUDY OFDRAG REDUCTION BY AERATION IN pipe flowS

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International Journal of Sediment Research 1999年第4期 31-36页

作者： ZHENG Yonggang(Project Supported by National Natural Science Foundation of China.)(Prof., Ph.D., Sichuan University, Chengdu 610065, P. R. China.)Notes: Discussion open open Until December 2000. The manuscript for this paper was received on 12 Feb. 1999

The paper studies the laws of drag reduction in aerated lanlinar and turbulent pipe flows. Thetheoretical study indicates that the resistance aeratcd 11ow is smaller than the flows without air at the sameflow. rate. For turbulent flow drag reduction occurs only when the air concentration at the wall region ishigher than that at the center of the pipe. The concepts of density turbulence stress and viscosityturbulence stress are proposed in the paper.

关键词： Stratified flow. Drag reduction Aeration Turbulence stress pipe flow

TRANSIENT flowS AND PRESSURE WAVES IN pipeS

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Journal of Hydrodynamics 1995年第2期7卷 51-59页

作者： Wang, Xiuqing Sun, J.G. Sha, W.T. Nuclear Industry Management Inst Beijing China

Transient laminar flows and pressure-wave propagation in pipes, commonly called as water hammer, have been analyzed. A pressure-wave equation and a linearized velocity equation were derived from the equations of mass and momentum conservation. The waveform distortion due to viscous dissipation and elastic expansion of pipe wall was characterized by a dimensionless transmission number. The damping coefficients of pressure waves were found to be related to the roots of Bessel function. An exact solution of pressure-wave equation was obtained numerically. The relationship between the distortion of a traveling wave and transmission number was studied. The problem was also calculated with a general-purpose computer code, COMMIX, which solves exact mass conservation equation and Navier-Stokes equations. The computational results of the COMMIX code agreed well with the analytical solutions.

关键词： Computer simulation Differential equations pipe flow Water wave effects

NORMAL MODES OF FLUID-STRUCTURE INTERACTION IN INTERNAL flowS

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Journal of Hydrodynamics 1998年第4期10卷 71-89页

作者： Zhang, Lixiang Huang, Wenhu Tijsseling, Arris S. Vardy, Alan E. Yunnan Polytechnic Univ Kunming China

The Information in frequency domain was deducted by a discrete Fourier transforms. The modal information of the fluid-structure interaction in internal flows was analyzed. The dispersive and dissipative term in a fully coupled manner can be treated. The method has been validated by comparison with an exact analytical solution, with the results obtained by discrete Fourier transform and an analysis using the method of characteristics as well as with measured data from a laboratory apparatus.

关键词： Dispersions Fourier transforms Frequency response Mathematical models pipe flow Vibrators