دانلود مقاله ترجمه شده نوآوری الگوی ساختار مایع تعاملی برای نانو لوله های کربنی – مجله الزویر

بخشی از ترجمه:

در این مقاله معادله حرکت لوله های انتقال سیال بررسی شده است. ما با استفاده از اصول مکانیک سیالات مانند مدل استوکس و همچنین چندین معیار در زمینه تعامل ساختار مایع(FSI) استفاده کرده ایم و نشان می دهد که ویسکوزیته جریان سیال باید در معادله حرکت سیال صدق کند. براساس این نتیجه ما می توانیم یک مدل ابتکاری برای ارتعاشات نانولوله های کربنی (CNT) ها را با استفاده از سرعت لغزش جریان سیال بر دیواره های CNT ارائه نموده و همچنین از نظریه زنجیره اثر اندازه نانوجریان و نانو ساختار را بررسی کردیم. بنابراین ابتکار در معادله FSI نشان می دهد که نانو لوله برای انتقال نانوجریان برای سرعت های بالاتر پایدارتر است. به عبارت دیگر به طور متوسط سرعت برای جریان سیال که در آن بی ثباتی اتفاق می افتد باید در مقایسه با سرعت بحرانی پیش بینی شده توسط مدل های مورد استفاده مانند پلاگین و نظریه های زنجیره کلاسیک کارساز باشد. ١-مقدمه: نانو لوله های کربنی در حال تبدیل شدن به مواد نانو الکتریک،نانودستگاه ها و نانوکامپوزیت ها برای استفاده در نانوپیپت ها،دیسک ها،راکتورها و دستگاه های فیلتراسیون مایع،حمل و نقل یون،دستگاه های داروسازی و میکروسکوپ های هدایت یون است. در این راستا تعداد قابل توجهی از مطالعات به افشای رفتار ارتعاشی از جمله نانوساختارها و انتقال سیال توسط آنها انجام شده است. در این تحقیق ما یک ارزیابی مجدد برای محاسبات مدل سازی CNT های چسبناک را با برخی از دیدگاه های تازه را انجام داده ایم. و سعی می کنیم به منظور توسعه آن قدم برداریم و معادله ای را با در نظر گرفتن شرایط لغزش برروی دیواره ناولوله ارائه دهیم. مورد مطالعه جریان مایعات چسبناک از طریق CNT و ایجاد یک توازن جدید حرکت لوله های انتقال مایع با درنظرگرفتن اثرویسکوزیته است. آنها دریافتند که یک نانولوله انتقال یک سیال لزج را در برابر کمانش لرزش ناشی از یک نانولوله غیر چسبناک را دارد. مدل سازی محاسباتی مایع چسبناک منتقل شده از CNT توسط خوسرویان و رفیعی تبار ارائه شده است. و پس از آن اصلاح معادله FSI و فاش کردن اثر ویسکوزیته جریان سیال در لرزش و بی ثباتی نانولوله ها باعث نادیده گرفتن می شود.

بخشی از مقاله انگلیسی:

abstract In this article, we reappraise the well-known equation of motion for a pipe conveying viscous fluid. We utilize prominent principles of fluid mechanics such as Navier–Stokes’ equation as well as several benchmark references in the field of fluid–structure interaction (FSI) to reveal that the viscosity of the fluid flow should not appear explicitly in the equation of motion of pipe conveying fluid. Based on this result, we could develop an innovative model for one dimensional coupled vibrations of carbon nano-tubes (CNTs) conveying fluid using slip velocity of the fluid flow on the CNT walls as well as utilizing size-dependent continuum theories to consider the size effects of nano-flow and nano-structure. Therefore, this innovative coupled FSI equation suggests that CNTs conveying nano-flow remain stable for higher velocities. In the other words, the critical average velocity of the fluid flow at which the divergence instability occurs, should be greater in comparison with the critical velocity predicted by the models used plug flow and classical continuum theories. 2013 Elsevier B.V. All rights reserved. 1. Introduction Carbon nano-tubes (CNTs) are becoming the most promising material for nano-electronics, nano-devices and nano-composites because of their enormous application such as nano-pipettes, actuators, reactors, fluid filtration devices, biomimetic selective transport of ions, targeted drug delivery devices, scanning molecule microscopy, and scanning ion conductance microscopy [1–4]. In this regard, a remarkable number of studies have been accomplished to disclose the vibrational behavior of such nano-structures conveying fluid. Tuzun et al. [5], Amabili et al. [6], Yoon et al. [7], Natsuki et al. [8], Wang et al. [9], Xia et al. [10] and Wang and Qiao [11] made important contributions in this practical area. In this research, we would undertake a reevaluation for computational modeling of carbon nano-tubes conveying viscous fluid with some fresh insights as well as we try to develop an innovative one dimensional (1D) coupled fluid–structure interaction (FSI) equation by considering slip condition on the nano-tube wall. Khosravian and Rafii Tabar [12] studied the flow of viscous fluid through a carbon nano-tube and established a new equation of motion of pipe conveying fluid by considering the viscosity effect. They found that a nano-tube conveying a viscous fluid was more stable against vibration-induced buckling than a nano-tube conveying a non-viscous fluid. Wang and Ni [13] reappraised the computational modeling of carbon nano-tube conveying viscous fluid represented by Khosravian and Rafii Tabar [12] and then corrected the FSI equation and disclosed that the effect of viscosity of fluid flow on the vibration and instability of CNTs could be ignored. Lee and Chang [14] analyzed the influences of nonlocal effect, viscosity effect, aspect ratio, and elastic medium constant on the fundamental frequency of a single-walled carbon nano-tube (SWCNT) conveying viscous fluid embedded in an elastic medium. They revealed that the frequency increased as the values of the viscosity parameter increased. Soltani et al. [15] developed a transverse vibrational model for a viscous fluid-conveying SWCNT embedded in biological soft tissue. Their investigation determined that the structural instability and the associated critical flow velocity could be affected by the viscosity of the fluid and the nonlocal parameter. Khoddami et al. [16] studied electro-thermo nonlinear vibration and instability of embedded double-walled Boron Nitride nano-tubes (DWBNNTs) conveying viscous fluid based on nonlocal piezoelasticity theory. They reported that increasing the small scale parameter decreased the real and imaginary parts of frequency and critical fluid velocity. Furthermore, they concluded that the effect of fluid viscosity on the vibration and instability of DWBNNTs might be ignored. In many recent studies various size-dependent continuum theories have been developed for vibration and stability analysis of CNTs conveying fluid.  Computational Materials Science 77 (2013) 161–171 Contents lists available at SciVerse ScienceDirect Computational Materials Science journal homepage: www.elsevier.com/locate/commatsci and Fang [18], Jannesari et al. [19] included the effect of small-size into equations of motion by using nonlocal elasticity in their studies and showed that increasing nonlocal parameter had the effect of a decrease in the critical velocity of fluid. Ke and Wang [20] investigated vibration and instability of fluid-conveying doublewalled carbon nano-tubes based on modified couple stress theory. They showed that the imaginary component of the frequency and the critical flow velocity of the CNTs increased with an increase in length scale parameter. Wang [21] developed a theoretical analysis of wave propagation of fluid-conveying single-walled carbon nanotubes based on strain gradient elasticity theory. He showed that the use of gradient elasticity theory had a dramatic effect on dispersion relation. Wang [22] utilized nonlocal elasticity theory integrated with surface elasticity theory to analyze dynamic response of nano-tubes conveying fluid. He revealed that fundamental frequency and critical flow velocity predicted by his new model was generally higher than that predicted by the Euler–Bernoulli beam model without surface effects. Some recent studies developed to consider the small size effects of nano-flow as well as slip boundary condition on nano-tube wall. For instance, Rashidi et al. [23] presented an original model for a single-mode coupled vibrations of nano-tubes conveying fluid by considering the slip boundary conditions of nano-flow quantified by Knudsen number (Kn). They reported, for the passage of gas through a nano-pipe with nonzero Kn, that the critical flow velocities could decrease considerably in comparison with a liquid nano-flow. Mirramezani and Mirdamadi [24] investigated coupled-mode flutter stability of nano-tube conveying gas and liquid nano-flow for different beam boundary conditions and multi-mode analysis. They observed that coupledmode flutter might occur much sooner by considering slip condition than that predicted by continuum theory. Kaviani and Mirdamadi [25] studied the wave propagation phenomena in CNT conveying fluid. The CNT structure was modeled by using sizedependent strain/inertia gradient theory of continuum mechanics, the CNT wall-fluid interaction by slip boundary condition and Knudsen number (Kn). They reported that Kn could impress complex wave frequencies at both lower and higher ranges of wave numbers, while the small-size had impression at the higher range. Mirramezani and Mirdamadi [26] investigated the effect of nanosize of both fluid flow and elastic structure simultaneously on the vibrational behavior of a nano-tube conveying fluid using both Kn and nonlocal continuum theory. It was observed that the nonlocal parameter would have more effect than Kn on the reduction of critical velocities of a liquid nano-flow. This effect had considerable impact on the reduction of critical velocities for a clamped– clamped beam in comparison with a pinned–pinned one. Kaviani and Mirdamadi [27] considered the coupled effects of Kn and slip boundary condition on the viscosity of a nano-flow passing through a nano-tube. Kn-dependent viscosity could affect both directly on viscosity values and indirectly on a dimensionless parameter, velocity correction factor, VCF, defined as the ratio of no-slip flow velocity to slip flow velocity on the boundaries of a nano-tube. They concluded that the effect of viscosity on the critical flow velocity could be so large that for a specific numerical study could reach one-fourth of that velocity, by ignoring the viscosity effect on slip boundary condition. Matin et al. [28] studied the effects of nonlocal elasticity and slip condition on vibration of nano-plate coupled with fluid flow. They reported that the effect of nonlocal parameter would be considerable for plate lengths less than 50 nm as well as when the fluid is a liquid, most of the contribution in decreasing critical flow velocity is due to nonlocal parameter but when the fluid is a gas, Kn has a greater role in decreasing the critical velocity. A partial objective of this study is to reappraise the equation of motion of pipe conveying viscous fluid extracted by Khosravian and Rafii Tabar [12]. In this article, we utilize basic principles of fluid mechanics such as Navier–Stokes’ equation; moreover, we benefit from some valuable classical works in the field of FSI to reveal that the viscosity of the fluid flow should not appear explicitly in the equation of motion. Furthermore, we propose a novel model, for 1D coupled vibrations of carbon nano-tubes (CNTs) conveying fluid, taking into account the slip boundary condition using Knudsen number as well as size-dependent continuum theories such as strain/inertia gradient and nonlocal theories. It could be seen that the current model by considering the size effects of nano-flow and nano-structure, the critical mean flow velocity at which the divergence-type instability might occur, could differ remarkably from that of a plug flow model for the fluid flow. The remainder of this study is organized as follows: In Section 2, we reappraise the equation of motion of pipe conveying viscous fluid. In Section 3, we develop an innovative 1D coupled FSI equation by considering slip condition and size-dependent continuum theories. In Section 4, we implement the Galerkin weighted-residual solution technique and solve the partial differential equations of nano-tube vibrations. In Section 5, we discuss stability analysis and present the results. Finally, in Section 6, we express our conclusions.