Viscosity Lab viscometer
Viscosity Lab Report.
CITY UNIVERITY
LONDON
SCHOOL OF ENGINEERING
AND MATHEMATICAL SCIENCES
1. Abstract.
In this experiment the viscosity of pure glycerol and a glycerol – water mixture are measured.
At the end of the test it is apparent that glycerol is a near perfect Newtonian fluid and that it is more viscous than water. We also can appreciate how viscosity varies within a given temperature range.
2. Introduction.
The purpose of this experiment was to find the viscosity of two differing mixtures of glycerol and water. Viscosity is an important fluid property for engineers, for it describes how the fluid deforms under stress. It could be colloquially defined as a fluid’s “thickness”.
Viscosity or “thickness” is important because it can describe how the fluid would flow, behave and what it can be used for. For example honey wouldn’t be used to shower with because it is very viscous and would clog the shower head, but water is perfect for this application. It is much less viscous and flows nicely out of the nozzle and over skin as opposed to the “thick” or “sticky” honey which would cling to skin due to internal forces, frictions, etc…
With this in mind, the experiment was carried out using a rotational viscometer. A viscometer is an apparatus that spins the fluid and measures the opposing force that the liquid exerts. A viscous fluid will oppose the spinning motion with a greater force than a mobile liquid. A mobile liquid is less viscous than water and a viscous liquid is more viscous than water.
There are two different types of liquid, a Newtonian liquid is a fluid who’s viscosity doesn’t vary with shear rate, a non-Newtonian liquid has the interesting property of it getting thicker or thinner depending on shear rate.
So is glycerol a Newtonian fluid and is it a mobile or viscous?
3. Theory.
Viscosity of a fluid is defined as the ratio between shear stress and shear rate. A fluid is considered a Newtonian fluid when
CITY UNIVERITY
LONDON
SCHOOL OF ENGINEERING
AND MATHEMATICAL SCIENCES
1. Abstract.
In this experiment the viscosity of pure glycerol and a glycerol – water mixture are measured.
At the end of the test it is apparent that glycerol is a near perfect Newtonian fluid and that it is more viscous than water. We also can appreciate how viscosity varies within a given temperature range.
2. Introduction.
The purpose of this experiment was to find the viscosity of two differing mixtures of glycerol and water. Viscosity is an important fluid property for engineers, for it describes how the fluid deforms under stress. It could be colloquially defined as a fluid’s “thickness”.
Viscosity or “thickness” is important because it can describe how the fluid would flow, behave and what it can be used for. For example honey wouldn’t be used to shower with because it is very viscous and would clog the shower head, but water is perfect for this application. It is much less viscous and flows nicely out of the nozzle and over skin as opposed to the “thick” or “sticky” honey which would cling to skin due to internal forces, frictions, etc…
With this in mind, the experiment was carried out using a rotational viscometer. A viscometer is an apparatus that spins the fluid and measures the opposing force that the liquid exerts. A viscous fluid will oppose the spinning motion with a greater force than a mobile liquid. A mobile liquid is less viscous than water and a viscous liquid is more viscous than water.
There are two different types of liquid, a Newtonian liquid is a fluid who’s viscosity doesn’t vary with shear rate, a non-Newtonian liquid has the interesting property of it getting thicker or thinner depending on shear rate.
So is glycerol a Newtonian fluid and is it a mobile or viscous?
3. Theory.
Viscosity of a fluid is defined as the ratio between shear stress and shear rate. A fluid is considered a Newtonian fluid when