perfact for medical student

1. viscometer
Typesof 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 typeof
viscometer.
 “Viscometersonly 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 viscosityofone liquid one can find the viscosity
of other liquid.

8. Falling Piston Viscometer

9.  The principle of viscosity measurement in this rugged & sensitive
industrialdevice is based on a piston & cylinder assembly.
 The piston is periodically raised by an air lifting mechanism,
drawing the materialbeing measured down through the
clearance (gap) b/w the piston & the wall of cylinder intothe
space which is formed below the piston as it is raised.

10. Falling Sphere Viscometer

11.  Stoke’slaw is the basis of the falling sphere viscometer, in which
the fluid is stationary in a verticalglass tube.
 A sphere of known size and density is allowed to descend
through the liquid.If correctly selected , it reachesterminal
velocity , which can be measured by the time it takes to pass two
marks on the tube.
 Knowing the terminalvelocity, the size and density of the
sphere, and the density of the liquid , Stoke’slaw 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.  Rotationalviscometer gathersdata on a material’s viscosity
behavior under different conditions.
 RotationalViscometerscan be used for the accurate
measurement of viscosity for both Newtonian & Non-
Newtonian.
Rotational Viscometer

15.  A vibrationalviscometer is used for continuousdirect
measurement of viscosity in pipes and / or tanks.
 Vibratory Viscometersare better suited to measure non-
Newtonian liquids.
Vibrational viscometer

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

17.  Efflux cup viscometersare most commonly used for fieldworkto
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
1ST PROFESSIONAL (PHARM-D)

20. THE END