This document discusses capillary viscometers, which are instruments used to determine the viscosity of Newtonian fluids. It explains that capillary viscometers operate based on Poiseuille's law, measuring the time it takes for a known quantity of fluid to flow through a capillary tube of defined diameter and length. Two common types are described - Ostwald viscometers and suspended level viscometers. A mathematical expression is provided to calculate the viscosity of an unknown liquid based on its flow time compared to a liquid of known viscosity. Examples of capillary viscometer applications in quality control, pharmaceuticals, chemicals, foods, and cosmetics are listed.

1. Smt .Maherbanu college of science &
commerce Akola .
Presented by : Munawwar Kaunain Guided by :Prof.chanchal rathi ma’am
Class: B . Tech( cosmetics ) 3rd
year sem – 5th
Topic : capillary viscometer

2. What is capillary viscometer ?????
Introduction
01
Principle behind capillary viscometer
02
( Mathematical expression) & formula
Types of Capillary viscometer , working
03
Application of capillary viscometer
04
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3. INTRODUCTION
What is capillary Viscometer ??
• It is a specialized device or instrument used for
determination of viscosity or flow properties of
Newtonian fluids only .
• Both dynamic & Kinametic viscosity obtained
• It is mostly stabilized for low viscous liquids..

4. Principle behind capillary viscometer
• It is based on poiseullie’s law .
• The Method of measurement that
measures time taken for defined
quantity of fluids to flow through a
capillary with known diameter and
length quantity and then compared
with a time required to flow by a
liquid of known viscosity.
• Usaully used water to determine the
viscosity of unknown liquid.

5. Ostwald viscometer
Suspended level
viscometer
Types of
viscometer

6. Ostwald viscometer
• Oswald viscometer is also known as
u- tube viscometer.
• A device which is used to measure
the viscosity of the liquid having
kown density.
• This device named after Wilhelm
Ostwald .

7. Mathematical expressions
Determination of
viscosity of
unknown liquid .
According to poiseuilles law the
relationship between flow of liquid
and capillary viscometer describe as
Where,
n2 = viscosity of unknown liquid
n1 = viscosity of the known liquid
t2 = time of flow of uknown liquid
t1= time of flow of known liquid
P1 = density of known liquid
P2 = density of unknown liquid liquid
N = viscosity of liquid 1 poise
r = radius of the inside diameter capillary
,cm
t= the time of flow in sec
∆p = pressure head dyne /cm2
L = length of the capillary , cm
V = volume of the liquid flowing cm3

8. Working of Ostwald viscometer
• A clean and dry Ostwald viscometer should be selected
and fixed firmly to a stand in a vertical position . With the
help of pipette a fixed amount of water is transferred
through a wide limb .
• Through the rubber tube water is sucked Through the upper
level water mark water allowed to flow down.
• When the water meniscus reach Mark ‘A’ the stop watch
started and hence water flow &reach Mark ‘B ‘then the stop
to take out reading .

9. Suspended level viscometer
• It is a modified from of Ostwald
viscometer.
• In it third vertical arm is attached to the
bulb of the capillary part of the right arm
• Liquid is introduced in the
• Viscometer through the left arm in
quantity sufficient to fill the bulb in the left
arm.
Suspended level
viscometer

10. Advantages and disadvantages
• Measure precise viscosities for
many diverse fluids.
• Small $Portable
• Inexpansive
• Easy to use
• Can use a wide variety of
capillary tubes on same
viscometer
• No single tube is
suitable for all viscosities
• Basic model can only be
used for Translucent
fluids.
• Difficult to clean the
capillary tube

11. Application of capillary viscometer
They are also used for jams & syrups that are used
for food preparations to determine consistent batches
1 3
4
2
Used in quality control
process in formulation
or evaluation of
pharmaceutical system
In chemical industry
Measured the fuel and
petroleums as well as seals and
lubricant to evaluate how they
does work in different
temperature
In food preparations
In cosmeceutical
For emulsion,suspension
and for low viscous fluid.