• Title/Summary/Keyword: fluid slip

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Wheel slip control of automotive brake system using ER valve (ER 밸브를 이용한 자동차 브레이크 시스템의 차륜 슬립제어)

  • 방주현;최승복
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.357-360
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    • 1997
  • This paper presents a new anti-lock brake system(ABS) using electro-rheological(ER) valve actuators for the wheel slip control. The hydraulic dynamic model of the automotive brake system is formulated by incorporating electric field-dependent Bingham properties of ER fluid obtained experimentally. The brake system designed by this hydraulic model is able to control wheel slip by controlling the intensity of electric field which tunes the braking torque. The control fields of the ER valve to command desired wheel slip are determined by a sliding mode controller. A comparison between the proposed brake system and the conventional brake system is made by providing with computer simulations of vehicle motions under ABS performance requirement condition.

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Sloshing Flow of Highly-Viscous Fluid in a Rectangular Box (사각용기에서 발생하는 고점성 유체의 슬로싱 유동)

  • park, Jun Sang
    • Journal of the Korean Society of Visualization
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    • v.17 no.3
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    • pp.39-45
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    • 2019
  • A study on the sloshing flow of highly-viscous fluid in a rectangular box was made by both of theoretical approach and experimental visualization method. Assuming a smallness of external forcing to oscillate the container, it was investigated a linear sloshing flow of highly-viscous fluid utilizing asymptotic analysis by Taylor-series expansion as a small parameter Re (≪1) in which Re denotes Reynolds number. The theory predict that, during all cycles of sloshing, a linear shape of free surface will prevail in a bulk zone and it has confirmed in experiment. The relevance of perfect slip boundary condition, adopted in theoretical approach, to the bulk zone flow at the container wall was tested in experiment. It is found that quasi-steady coated thin film, which makes a lubricant layer between bulk flow and solid wall, is generated on the wall and the film makes a role to perfect slip boundary condition.

A study on Low-Noise and High-Efficiency Sirocco Fan Development (저소음 고효율 시로코 홴 개발에 관한 연구)

  • Park, Kwang-Jin;Lee, Sang-Hwan;Son, Byung-Jin
    • The KSFM Journal of Fluid Machinery
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    • v.2 no.2 s.3
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    • pp.46-56
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    • 1999
  • This study is on the performance prediction and design of a sirocco fan. Slip coefficient is very important factor for the performance analysis of a centrifugal-type fan. Because generally used slip coefficient equations of backward curved centrifugal fan are not appropriate for forward curved sirocco fan, in this study a proper slip coefficient equation for a sirocco fan is suggested. Using this equation performance prediction program for sirocco fan is composed of and also included the total noise prediction that include the turbulent noise at the fan inlet and boundary layer noise. A comparison between the values obtained from performance prediction program and experimental values shows that the program predicts the sirocco fan performance in a practical rate.

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Combined influence of slip parameter and Reynolds number on Casson nanofluid flowing in stretching cylinder

  • Jalil, Mudassar;Hussain, Muzamal;Khadimallah, Mohamed A.;Iqbal, Waheed;Loukil, Hassen;Mouldi, Abir;Mahmoud, S.R.;Tounsi, Abdelouahed
    • Computers and Concrete
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    • v.30 no.5
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    • pp.369-375
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    • 2022
  • Current exertion reports the numerical analysis of boundary layer slip flow of Casson Nano fluid along a permeable cylinder that is stretching in exponential manner. The modeled PDEs are changed into nonlinear ODEs through appropriate nonlinear transformations. Numerical results are attained using a renowned numerical scheme shooting method with Runge-Kutta procedure of 6th-order. Influential role of relevant parameters like Reynolds, suction, Casson fluid and slip parameters on velocity profile is investigated. The effect of influence of slip parameter γ on temperature profile is seen through graph. To ensure the authenticity of numerical procedure, outcomes of some special cases of present work are compared with published work and strong agreement is noticed.

Lubrication phenomenon in the stagnation point flow of Walters-B nanofluid

  • Muhammad Taj;Manzoor Ahmad;Mohamed A. Khadimallah;Saima Akram;Muzamal Hussain;Madeeha Tahir;Faisal Mehmood Butt;Abdelouahed Tounsi
    • Advances in concrete construction
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    • v.15 no.5
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    • pp.303-312
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    • 2023
  • The present study investigates the effects of Cattaneo-Christov thermal effects of stagnation point in Walters-B nanofluid flow through lubrication of power-law fluid by taking the slip at the interfacial condition. For the solution, the governing partial differential equation is transformed into a series of non-linear ordinary differential equations. With the help of hybrid homotopy analysis method; that consists of both the homotopy analysis and shooting method these equations can be solved. The influence of different involved constraints on quantities of interest are sketched and discussed. The viscoelastic parameter, slip parameters on velocity component and temperature are analyzed. The velocity varies by increase in viscoelastic parameter in the presence of slip parameter. The slip on the surface has major effect and mask the effect of stagnation point for whole slip condition and throughout the surface velocity remained same. Matched the present solution with previously published data and observed good agreement. It can be seen that the slip effects dominates the effects of free stream and for the large values of viscoelastic parameter the temperature as well as the concentration profile both decreases.

The Effect of Suction and Injection on Unsteady Flow of a Dusty Conducting Fluid in Rectangular Channel

  • Attia Hazem Ali
    • Journal of Mechanical Science and Technology
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    • v.19 no.5
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    • pp.1148-1157
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    • 2005
  • In the present study, the unsteady Hartmann flow of a dusty viscous incompressible electrically conducting fluid under the influence of an exponentially decreasing pressure gradient is studied without neglecting the ion slip. The parallel plates are assumed to be porous and subjected to a uniform suction from above and injection from below. The fluid is acted upon by an external uniform magnetic field which is applied perpendicular to the plates. An analytical solution for the governing equations of motion is obtained to yield the velocity distributions for both the fluid and dust particles.

MHD Pulsatile Flow and Heat Transfer of Two Immiscible Couple Stress Fluids Between Permeable Beds

  • Kumar, Deepak;Agarwal, Manju
    • Kyungpook Mathematical Journal
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    • v.61 no.2
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    • pp.323-351
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    • 2021
  • The present paper addresses magnetohydrodynamic pulsating flow and heat transfer of two immiscible, incompressible, and conducting couple stress fluids between two permeable beds. The flow between the permeable beds is assumed to be governed by Stokes' [28] couple stress fluid flow equations, whereas the dynamics of permeable beds is determined by Darcy's law. In this study, matching conditions were used at the fluid-fluid interface, whereas the B-J slip boundary condition was employed at the fluid-porous interface. The governing equations were solved analytically, and the expressions for velocity, temperature, mass flux, skin friction, and rate of heat transfer were obtained. The analytical expressions were numerically evaluated, and the results are presented through graphs and tables.

INFLUENCE OF SLIP CONDITION ON RADIATIVE MHD FLOW OF A VISCOUS FLUID IN A PARALLEL POROUS PLATE CHANNEL IN PRESENCE OF HEAT ABSORPTION AND CHEMICAL REACTION.

  • VENKATESWARLU, M.;VENKATA LAKSHMI, D.;DARMAIAH, G.
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.20 no.4
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    • pp.333-354
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    • 2016
  • The present investigation deals, heat and mass transfer characteristics with the effect of slip on the hydromagnetic pulsatile flow through a parallel plate channel filled with saturated porous medium. Based on the pulsatile flow nature, exact solution of the governing equations for the fluid velocity, temperature and concentration are obtained by using two term perturbation technique subject to physically appropriate boundary conditions. The expressions of skin friction, Nusselt number and Sherwood number are also derived. The numerical values of the fluid velocity, temperature and concentration are displayed graphically whereas those of shear stress, rate of heat transfer and rate of mass transfer at the plate are presented in tabular form for various values of pertinent flow parameters. By increasing the slip parameter at the cold wall the velocity increases whereas the effect is totally reversed in the case of shear stress at the cold wall.

Study on The Slip Factor Model for Multi-Blades Centrifugal Fan (원심다익송풍기의 미끄럼 계수에 대한 연구)

  • GUO, En-min;KIM, Kwang-Yong;SEO, Seoung-Jin
    • 유체기계공업학회:학술대회논문집
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    • 2002.12a
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    • pp.111-115
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    • 2002
  • The objective of this work is to develop improved slip factor model and correction method to predict flow through impeller in forward-curved centrifugal fan by investigating the validity of various slip factor models. Both steady and unsteady three-dimensional CFD analyses were performed with a commercial code tn validate the slip factor model and the correction method. The results show that the improved slip factor model presented in this paper could provide more accurate predictions for forward-curved centrifugal impeller than the other slip factor models since the presented model takes into account the effect of blade curvature. The comparison with CFD results also shows that the improved slip factor model coupled with the present correction method provides accurate predictions for mass-averaged absolute circumferential velocity at the exit of impeller near and above the flow rate of peaktotal pressure coefficient.

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ACCURATE SOLUTION FOR SLIDING BURGER FLUID FLOW

  • ZUBAIR, MUHAMMAD;HAYAT, TASAWAR
    • Journal of applied mathematics & informatics
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    • v.37 no.5_6
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    • pp.429-442
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    • 2019
  • This article addresses the influence of partial slip condition in the hydromagnetic flow of Burgers fluid in a rotating frame of reference.The flows are induced by oscillation of a boundary. Two problems for oscillatory flows are considered. Exact solutions to the resulting boundary value problems are constructed. Analysis has been carried out in the presence of magnetic field. Physical interpretation is made through the plots for various embedded parameters.