Viscometer slide

perfact for medical student

1. viscometer
Types of Viscometer
&
Their Descriptions

2. Viscosity
Viscometer
Types of Viscometer

CONTENTS

3. The viscosity of a fluid is a measure of its resistance to gradual
deformation by shear stress or tensile stress.

Units of Viscosity……

1.Poise

2.Centipoise
VISCOSITY

4. A viscometer (also called viscosimeter) is an instrument used to
measure the viscosity of a fluid.
 For liquids with viscosities which vary with flow conditions,
an instrument called a rheometer is used.
 Thus, a rheometer can be considered as a special type of
viscometer.



 “Viscometers only measure under one flow condition.”
What is Viscometer ?

5. 1.Ostwald Viscometer
2.Falling Piston Viscometer
3.Falling Sphere Viscometer
4.Oscillation Viscometer
5.Rotational Viscometer
6.Vibrational Viscometer
7.Saybolt Viscometer & many others……
“Types of Viscometer”

6. Ostwald’s Viscometer

7. “Ostwald’s Viscometer, also known as U-Tube
viscometer, is a device which is used to measure the
viscosity of the liquid with a known density.”
This device is named after “Wilhelm Ostwald.”
Measurement:
The method consist of measuring the time foe a known volume
of the liquid (the volume contained between the marks A& B) to
flow through the capillary under the influence of gravity.
By knowing the viscosityof one liquid one can find the viscosity
of other liquid.

8. Falling Piston Viscometer

9. The principle of viscosity measurement in this rugged & sensitive
industrial device is based on a piston & cylinder assembly.

The piston is periodically raised by an air lifting mechanism,
drawing the material being measured down through the
clearance (gap) b/w the piston & the wall of cylinder into the
space which is formed below the piston as it is raised.

10. Falling Sphere Viscometer

11. Stoke’s law is the basis of the falling sphere viscometer, in which
the fluid is stationary in a vertical glass tube.
A sphere of known size and density is allowed to descend
through the liquid.If correctly selected , it reaches terminal
velocity , which can be measured by the time it takes to pass two
marks on the tube.
Knowing the terminal velocity, the size and density of the
sphere, and the density of the liquid , Stoke’s law can be used to
calculate the viscosity of the fluid.

12. Oscillation Viscometer
The oscillating piston viscometer technology has been adapted foe
small sample viscosity & micro-sample viscosity testing in laboratory
applications.

13. It has been adapted to measure high pressure viscosity & high
temperature viscosity measurements in both laboratory & process
environments.

14. Rotational viscometer gathers data on a material’s viscosity
behavior under different conditions.
Rotational Viscometers can be used for the accurate
measurement of viscosity for both Newtonian & Non-
Newtonian.
Rotational Viscometer

15. A vibrational viscometer is used for continuous direct
measurement of viscosity in pipes and / or tanks.
Vibratory Viscometers are better suited to measure non-
Newtonian liquids.
Vibrational viscometer

16. A device used to measure the viscosity of a fluid.The saybolt
viscometer controls the heat of the fluid & the viscosity is the
time to take the fluid to fill the container.

Saybolt Viscometer

17. Efflux cup viscometers are most commonly used for fieldwork to
measure the viscosity of oils, syrups, varnish, paints & Bitumen
emulsions.
The saybolt viscometer , one of the efflux cup viscometers is the
standard instrument for testing petroleum products.
The testing procedure is quite similar to the capillary-tube viscometers.

18. PREPARED BY:-
MOHAMMAD MUNAWAR
SHEHZAD HASHMI
1
ST
PROFESSIONAL (PHARM-D)

20. THE END