COMPARISON OF THE RHEOLOGICAL PROPERTIES

Comparison of the Rheological Properties of Different Materials

Comparison of the Rheological Properties of Different Materials

Simulation based Modelling.

[Student Name and Supervisor Name]

Research CentreCollege of Engineering

Swansea University

Swansea UK

e-mail address of Student

Abstarct.

This paper is based on the study of different research methods to study and model the properties of materials and model them accoeding to the property wise classification as needed by the engineers for quick referencing.

Introduction

Rheology

The study of deformation and flow of materials, including elastic, viscous and elastic properties.

Viscosity Measurement of the internal friction of the liquid. this friction occurs between layers of fluid as it moves. The more friction, the more force must be applied to cause movement (“shift”).

The shift takes place in physical movement or destruction of the liquid: spills, spreading, spraying, mixing, etc. to shift the high viscosity liquids need to make more power than the low viscosity materials.

By the nature of the fluid flow (and pseudo liquid) is divided by the Newtonian and non Newtonian fluid, and the behaviour of the time on the thyrotrophic and reopeksnye.

Discussion

Newtonian and non Newtonian fluids

Fluid for which the viscosity is independent of the rate of deformation, called Newton. Typical Newtonian

fluids are water and low viscosity motor fuels. Behaviour of Newtonian fluids is well seen in the plot of shear stress (a) and viscosity (b) of the shear rate.

in practice, to designate to the viscosity of the liquid at a given temperature is constant and does not depend on the model viscometer, spindle or shear rate. Standard Brookfield viscosity is also Newtonian fluids and is suitable for all models of Brookfield viscometer.

for non Newtonian fluids viscosity varies with shear rate. for these fluids viscometer model, spindle and shear rate affect the final result, for non Newtonian fluids, so called “apparent viscosity.” accuracy and reproducibility of the results for these fluids can be achieved only by playing all measurement parameters (model viscometer, spindle, temperature, etc.).

There are several types of non Newtonian fluids with different vliyaneniem shear viscosity. The best known are of three types:

pseudo plastic fluid

dilatants fluid

plastic fluid

Pseudo plastic viscosity liquids decreases with increasing shear rate.



The most famous pseudo plastic fluids paints, emulsions, and some suspension. To understand this behaviour, imagine that at the time of the spindle in the sample structure of molecules of a substance will change, they will seek to accommodate the movement of the surface parallel to the spindle. As a result, the resistance between the individual layers of the liquid will diminish strength to decline. With the acceleration of rotation of the original structure will break down the molecules will slide relative to each other, and strength will be reduced.

In dilatants fluids, on the contrary, with increasing shear rate viscosity increases.

Although dilatants fluids are not common, but they are quite a lot, this includes most deflocculates: clay suspensions, sweet mixture of corn starch suspension in water systems, sand / water.

Plastic fluid in static conditions behaves as solids, but when exposed to a certain power they begin to ...