Peristaltic Pumping of a Non-Newtonian Fluid

The flow induced by sinusoidal peristaltic motion of the tube wall of a non-Newtonian fluid obeying Herschel-Bulkley equation (a general rheological equation that represents a powerlaw, Bingham and Newtonian fluid for particular choice of parameters) under long wavelength and low Reynolds number approximation is investigated. The results obtained for flow rate, pressure drop and friction force are discussed both qualitatively and quantitatively and compared with other related studies. It is found that the pressure drop increases with the flow rate and yield stress but decreases with the increasing amplitude ratio. The flow behaviour index shows significant impact on the magnitude of the pressure drop. The pressure-flow rate relationships in Bingham and Newtonian fluid models are found to be linear whereas the same are non-linear in power- law and Herschel-Bulkley models. The friction force possesses the character similar to the pressure drop (an opposite character to the pressure rise) with respect to any parameter

Peristaltic transport of a two-layered fluid in a catheterized tube

The flow of a two-layered Newtonian fluid induced by peristaltic waves in a catheterized tube has been investigated. The expressions for the flow characteristics- the flow rate, the pressure drop and the friction forces at the tube and catheter wall are derived. It is found that the pressure drop increases with the flow rate but decreases with the increasing peripheral layer thickness and a linear relationship between pressure and flow exists. The pressure drop increases with the catheter size (radius) and assumes a high asymptotic magnitude at the catheter size more that the fifty percent of the tube size. The friction forces at the tube and catheter wall posses characteristics similar to that of the pressure drop with respect to any parameter. However, friction force at catheter wall assumes much smaller magnitude than the corresponding value at the tube wall

Peristaltic Induced Flow of a Particulate Suspension in a Non-Uniform Geometry

The flow induced by sinusoidal peristaltic waves of a particle-fluid suspension in a twodimensional diverging channel under low Reynolds number and long wavelength approximation has been investigated. The analytical expression for the flow characteristics-the flow rate, pressure rise and friction force have been derived. Moreover, we present some results concerning the dependence of these quantities on the geometrical parameters

A macroscopic two-phase blood flow through a stenosed artery with permeable wall

Abstract. The present paper concerns with the fluid mechanical study on the effects of the permeability of the wall through an overlapping stenosis in an artery assuming that the flowing blood is represented by a macroscopic two-phase model. The expressions for the blood flow characteristics, the impedance, the wall shear stress distribution in the stenotic region, shearing stress at the stenosis throats and at the stenosis critical height have been derived. Results for the effects of permeability as well as of hematocrit on these blood flow characteristics are shown graphically and discussed briefly

Blood Flow through a Composite Stenosis in an Artery with Permeable Wall

The present work concerns the fluid mechanical study on the effects of the permeability of the wall through an artery with a composite stenosis. The expressions for the blood flow characteristics, the flow resistance, the wall shear stress, shearing stress at the stenosis throat have been derived. Results for the effect of permeability on these flow characteristics are shown graphically and discussed briefly

Peristaltic Induced Flow of a Two-Layered Suspension in Non-Uniform Channel

Peristaltic transport of a two-layered particulate suspension in a non-uniform channel has been investigated. The coupled differential equations for both the fluid and the particle phases in the central as well as in the peripheral layers have been solved and the expression for the flow rate, the pressure rise and the friction force has been derived. The results obtained are discussed both qualitatively and quantitatively in brief. The significance of the particle concentration as well as the peripheral layer has been well explained

Modeling of an active suspension system with different suspension parameters for full vehicle

An active suspension system attempts to overcome these compromises so as to provide the best performance for controlling the vehicle. A fully active suspension system aims to control the suspension over the full bandwidth, increase load carrying capacity, handling and ride quality. A model for vehicle’s dynamics while using an active suspension system has been developed. The equations are cast in both the state space form and transfer function forms. To compare the ideal system and a real system, a comparative analysis is also performed by incorporating various sensing and actuation constraints such as time delay and discrete sampling. Simple PID as well as feed-forward controllers is designed and the response is simulated for various disturbances such as road excitations and those arising due to cornering. Parameter studies are also performed to assess the response to various suspension properties. The comparison of the active suspension with respect to the passive suspension indicates significant improvement in performance characteristics such as riding comfort, tendency to rollover and road traction. The studies on the effect of sensing and actuation constraints provide valuable insights into the use of low-cost and/or robust control system elements. Full vehicle model, State space equation, Passive and active suspension system, PID controller, Road profile, MATLAB and SIMULIN

Modeling of an active suspension system with different suspension parameters for full vehicle

55-63An active suspension system attempts to overcome these compromises so as to provide the best performance for controlling the vehicle. A fully active suspension system aims to control the suspension over the full bandwidth, increase load carrying capacity, handling and ride quality. A model for vehicle’s dynamics while using an active suspension system has been developed. The equations are cast in both the state space form and transfer function forms. To compare the ideal system and a real system, a comparative analysis is also performed by incorporating various sensing and actuation constraints such as time delay and discrete sampling. Simple PID as well as feed-forward controllers is designed and the response is simulated for various disturbances such as road excitations and those arising due to cornering. Parameter studies are also performed to assess the response to various suspension properties. The comparison of the active suspension with respect to the passive suspension indicates significant improvement in performance characteristics such as riding comfort, tendency to rollover and road traction. The studies on the effect of sensing and actuation constraints provide valuable insights into the use of low-cost and/or robust control system elements

Suspension Two-Layered Blood Flow Through a Bell Shaped Stenosis in Arteries

The present study concerns with the effects of the hematocrit and the peripheral layer on blood flow characteristics due to the presence of a bell shaped stenosis in arteries. To account for the hematocrit and the peripheral layer, the flowing blood has been represented by a two-layered macroscopic two-phase (i.e., a suspension of red cells in plasma) model. The expressions for the flow characteristics, namely, the velocity profiles, the flow rate, the impedance, the wall shear stress in the stenotic region and the shear stress at the stenosis throat have been derived. The quantitative effects of the hematocrit and the peripheral layer on these flow characteristics have been displayed graphically and discussed briefly

A Macroscopic Two-Phase Blood Flow Through a Stenosed Artery with Permeable Wall

The present paper concerns with the fluid mechanical study on the effects of the permeability of the wall through an overlapping stenosis in an artery assuming that the flowing blood is represented by a macroscopic two-phase model. The expressions for the blood flow characteristics, the impedance, the wall shear stress distribution in the stenotic region, shearing stress at the stenosis throats and at the stenosis critical height have been derived. Results for the effects of permeability as well as of hematocrit on these blood flow characteristics are shown graphically and discussed briefly