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DESIG� A�D DEVELOPME�T OF A DY�AMIC-

ACTIVE CLOTH WASHI�G PROCESS

BY

HEAP YEE �EA�

(0730510151)

A thesis submitted

In fulfilment of the requirements for the degree of Master of Science

(Manufacturing Engineering)

School of Manufacturing

U�IVERSITI MALAYSIA PERLIS

2010

© This item is protected by original copyright

ACK�OWLEDGME�T

The author would like to express gratitude and thanks to Dr. Ryspek for all his

help, patience, and guidance that have made this research possible. Thank you also to Dr.

Zaki for his passion and constant support in this research project. Thanks Dr. Khairul for

serving as part of member in manufacturing school graduate committee and organizing

research meeting and talk to improve the research quality. Sincere thanks goes to En.

Faizal and En. Nazri for their technical support and used of laboratory facility throughout

the research activity.

A special thanks to Chong Fee Wah and Chua Hui Min for volunteering their time

for this project. Not to forget Dr. Iqbar, Mr. Lim and En. Nabil for their guidelines in

running the statistical software. Finally, the author would like to thanks her parents for

their constant encouragement and support for making all this possible.

iii


REKABE�TUK DA� PEMBA�GU�A� PROSES AKTIF-

DI�AMIK PE�CUCIA� PAKAIA�

ABSTRAK

Tesis ini menerangkan tentang tahap kecekapan suatu proses pencucian baru yang

direka cipta. Suatu model makmal telah dibangunkan agar kaedah pencucian baju baru

iaitu secara aktif dan dinamik dapat dikaji. Proses baru ini menggunakan prinsip cucian

mekanikal di mama ia menggabungkan tindakan pulasan dan gosokan akibat tindakan

hidrodinamik air dan kesan jet air untuk membersihkan baju. Pergerakan air yang

komplek dan dinamik memberi interaksi secara terus antara air dan baju di mana

pembersihan aktif yang lebih produksif boleh didapati. Dalam kajian pembersihan baju,

jurutera menumpukan perhatian dengan mengkaji faktor seperti masa cucian, suhu, dan

tindakan mekanikal untuk meningkatkan kualiti cucian. Tindakan mekanikal adalah

bergantung kepada daya putaran atau kesan kacauann daripada tindakan pergerakan air

terhadap baju yang dicuci semasa proses pencucian berlaku. Tujuan kajian ini ialah untuk

mencari faktor utama yang mempengaruhi output cucian secara optima untuk proses

cucian berkaitan. Perbandingan data antara aktif proses daripada model makmal dan pasif

proses daripada mesin basuh Samsung WA91U3 dari segi keupayaan mencuci pakaian

dibandingkan. Hasil data menunjukkan faktor utama yang dapat memberi kesan cucian

optima kepada proses aktif ditentukan oleh masa manakala proses pasif bergantung

terutamanya kepada kelajuan cucian. Kadar lunturan kotoran daripada baju menunjukkan

proses cucian secara aktif adalah hampir 50% lebih baik daripada proses cucian secara

pasif yang dibanding.

iv


DESIG� A�D DEVELOPME�T OF A DY�AMIC-ACTIVE

CLOTH WASHI�G PROCESS

ABSTRACT

This thesis describes washing performance of a new introduced washing process.

A laboratory washing model is developed to simulate the dynamic-active cloth washing

process. It is the mechanical washing principle which combines deflection and abrasion

actions due to hydrodynamic and impact water jet working liquid to wash the cloth.

Complex dynamic fluid motion creates direct interaction between working liquid and

washed cloth hence produce active washing. In the washing machine research area,

engineer is interested in improving the washing performance by investigating its washing

time, temperature and the mechanical action that depend on motion of rotating force or

agitation effect acting on the washed cloth. The purpose of this study is to find the major

contributing factor to optimum washing of the washing process. Data comparison in term

of the washing efficiency has been performed between the laboratory developed model

and the commercial washing machine modelled Samsung WA91U3. Result shows that the

most significant factor contributes to optimum washing for developed model is washing

time while the commercial washing machine depends major on the washing speed. Soil

removal test indicates dynamic-active cloth washing process of developed laboratory

model is about 50% more efficient than the current washing machine compared.

v


CO�TE�TS

CHAPTER TITLE PAGE

TITLE i

DECLARATIO� ii

ACK�OWLEDGME�T iii

ABSTRAK iv

ABSTRACT v

CO�TE�TS vi

LIST OF TABLES x

LIST OF FIGURES xii

LIST OF APPE�DICES xv

I I�TRODUCTIO�

1.1 DESCRIPTION OF WASHING PROCESSES 1

1.2 EFFECT OF CLEANING ON FIBERS 2

1.3 HISTORY OF WASHING MACHINE 4

1.4 CLOTH CLEANING METHOD 6

vi


1.4.1 Wet Cleaning 6

1.4.2 Dry Cleaning 6

1.4.3 Ozone Cleaning System 7

1.4.4 Ultrasonic cleaning 7

1.5 STATEMENT OF PROBLEM 8

1.6 PURPOSE 8

1.7 SCOPE OF THE STUDY 9

II REVIEW OF LITERATURE

2.1 VERTICAL AND HORIZONTAL WASHING

MACHINE 11

2.2 SINNER’ CIRCLE 13

2.2.1 Mechanical Action 14

2.2.1.1 Mechanical G-factor 15

2.2.1.2 Abrasion and deflection cleaning 16

2.2.1.3 Drum construction 17

2.2.2 Chemical action 18

2.2.3 Washing time 20

2.2.4 Temperature influence 20

2.2.5 Water consumption 21

2.3 BLADE DESIGN 22

2.4 ACTIVE AND PASSIVE WASHING PROCESS 23

vii


2.4.1 Passive Washing Process 23

2.4.2 Active Washing Process 24

2.4.3 Advantage of Active Washing Process 26

2.5 MECHANICS OF DYNAMIC WASHED FLUID 26

2.5.1 Mechanical Action of Hydrodynamic Flow 30

III METHODOLOGY

3.1 DESIGN PROCESS 32

3.2 EQUIPMENT 41

3.3 MATERIAL 42

3.3.1 Soiled Fabrics 42

3.3.2 Detergents 43

3.3.3 Test Method 43

3.3.3.1 Washing Conditions 43

3.3.3.2 Experimental Procedure 48

3.3.3.3 Observation of the Sample 52

3.3.3.4 Washing Efficiency 53

3.4 REFLECTANCE AND CLEANLINESS RELATION 53

3.5 DESIGN OF EXPERIMENT 55

3.6 SCALING THEORY 60

viii


IV RESULTS A�D DISCUSSIO�

4.1 RESULTS 62

4.2 DISCUSSION 68

4.3 REGRESSION MODEL 73

4.4 SUMMARY OF FINDING 73

V CO�CLUSIO�

5.1 RECOMMENDATION 76

5.2 FUTURE OF ACTIVE WASHING TECHNOLOGY 77

REFERE�CE 79

APPE�DIX 83

GLOSSARY 103

ix


LIST OF TABLES

TABLE TITLE PAGE

Table 1.1 Fibre Strength 4

Table 1.2 Abrasion Resistances of Fibres 4

Table 2.1 Comparison between Top and Front Loader Washer

(Mescavage, Jun 2002) 13

Table 3.1 Bill of Material of Developed Active Washing Model 35

Table 3.2 Washing Condition and Experimental Parameter Setting 47

Table 3.3 Guidelines for Designing an Experiment 57

Table 3.4 2 Level Factorial Designs for Active Washing Process 59

Table 3.5 2 Level Factorial Designs for Passive Washing Process 59

Table 4.1 Pre-washed Data for Active Washing Process 63

Table 4.2 Data Compilation for Active Washing Process 63

Table 4.3 Analysis of Variance of Soil Removal Test

(Active Washing Process) 64

Table 4.4 Analysis of Variance of Soil Removal Test

(Passive Washing Process) 64

Table 4.5 Nozzle Inclination and Washing Efficiency Relation


x


Table 4.6 Washing Time Consumption and Washing Efficiency Relation


Table 4.7 Water Flow Rate and Washing Efficiency Relation


Table 4.8 Washing Time Consumption and Washing Efficiency Relation


Table 4.9 Water Speed and Washing Efficiency Relation


xi


LIST OF FIGURES

FIGURE TITLE PAGE

Figure 1.1 Old Manual Washing Machine (Kessler, 2008) 5

Figure 1.2 Samsung WA91U3 Washing Machine 10

Figure 2.1 Front Loader Washer 12

Figure 2.2 Top Loader Washer 12

Figure 2.3 Concept of Sinner’s Circle (Mescavage, July 2002) 14

Figure 2.4 Mechanical G-factor (Vinci, 2001) 16

Figure 2.5 Chemical Actions during Washing Process (Fanson, 1989) 19

Figure 2.6 Enzyme Activity versus pH Washing Liquor (Fanson, 1989) 20

Figure 2.7 Savinase Relative Activity versus Temperature at pH 9

(Novozymes, 2009) 21

Figure 2.8 Dual Action Agitator (Suggs, 1997) 22

Figure 2.9 Radial Extension for Single Action Agitator (Suggs, 1997) 22

Figure 2.10 Passive Washing Process 24

Figure 2.11 Active Washing Process 25

Figure 2.12 Effect of Active Flow on a Sample Cloth 25

Figure 2.13 Ring Formation from Opposing Vortices (Okamura, 2006) 27

Figure 2.14 Twin Opposing Vortex Pattern (Okamura, 2006) 27

xii


Figure 2.15 Vortex Vector in Central of Ring Formation (Okamura, 2006) 28

Figure 2.16 Cross Section View of Vortex Vector in Central of Ring Formation

(Okamura, 2006) 29

Figure 2.17 Pressure Distributions at Central of Ring Formation

(Okamura, 2006) 29

Figure 3.1 Overall System of Washing Model Assembly Unit 34

Figure 3.1.1 Detail Construction of Washing Drum 35

Figure 3.2 Active Flow at Cycle One 37

Figure 3.3 Squeezing Effect at Cycle One 37

Figure 3.4 Active Flow at Cycle Two 38

Figure 3.5 Squeezing Effect at Cycle Two 38

Figure 3.6 Conceptual Design of Passive Washing Process 40

Figure 3.7 Conceptual Design of Active Washing Process 40

Figure 3.8 Soil Strip Sample 42

Figure 3.9 Nozzle Angle, φ Acting on Centre Mass of Rotating Body 45

Figure 3.10 Centrifugal Force Created by Spinning Mass 46

Figure 3.11 Nozzle Angle Deflection 47

Figure 3.12 Swatch Quadrant Division 48

Figure 3.13 Towel Folding Instruction 48

Figure 3.14 Cloth Loading Sequence 49

Figure 3.15 Experimental Method Flow Chart 51

Figure 3.16 Radiometer Image 52

Figure 3.17 Radiometer Probe 52

xiii


Figure 3.18 Lightness or Value Identifies the Total Quantity of Light

(MacEvoy, 2001) 54

Figure 3.19 Geometric View of 23 Factorial Designs 58

Figure 4.1 Response of Cleanliness as a Function of Nozzle Inclination

Angle for Active Washing Process 68

Figure 4.2 Response of Cleanliness as a Function of Washing Time for

Active Washing Process 68

Figure 4.3 Response of Cleanliness as a Function of Water Flow Rate for

Active Washing Process 69

Figure 4.4 Response of Cleanliness as a Function of Washing Time for

Passive Washing Process 69

Figure 4.5 Response of Cleanliness as a Function of Washing Speed for

Passive Washing Process 70

Figure 4.6 Effect of Washing Time on Cleanliness for Active and Passive

Washing Process based on the Same Ratio Studied 70

Figure 4.7 Effect of Washing Speed on Cleanliness for Active and Passive

Washing Process based on the Same Ratio Studied 71

xiv


LIST OF APPE�DICES

APPE�DIX TITLE PAGE

Appendix I Revolution of washing machine 83

Appendix II Samsung washing machine model WA91U3

specification 84

Appendix III Forces exert on a fluid element 85

Appendix IV Model construction of active washing process 90

Appendix V Soil strip attachment and its folding procedure 91

Appendix VI Radiometer technical specification 92

Appendix VII Pre-washed data for active washing process (Day 1, 2) 93

Appendix VIII Post-washed data for active washing process (Day 1, 2) 95

Appendix IX Data compilation for active washing process (Day 1, 2) 97

Appendix X Pre-washed data for passive washing process 99

Appendix XI Post-washed data for passive washing process 100

Appendix XII Data compilation for passive washing process 101

Appendix XIII Statistical formula for analysis of variance 102

xv


1

CHAPTER I

ITRODUCTIO

Cloth cleaning aims to separate soil, odour sources and stains from fabric. It is a

two-step- process which involves “get it off” and “keep it off.” From the wet cleaning

point of view of, this process consists of wetting a fabric and the soil, odour source or

stain in order to separate the problem from the fabric. Holding the soil, odour source or

stain away from the fabric is to prevent it from soiling the fabric again during the

cleaning process.

1.1 DESCRIPTIO OF WASHIG PROCESSES

In general, cloth washing process can mainly divided into two major processes

which are under influence of mechanical and chemical actions.

Mechanical agitation removes dirt from a garment by either direct force or by

breaking and pulverizing dirt particles. Breaking and pulverizing results in smaller

particles, which are able to leave the fabric structure more easily. These smaller particles

are able to leave the fabric more easily than larger particles.


2

Chemical action taken place by adding certain chemicals to water can help water

clean more effectively. These chemical additives are called “surfactants” because of their

effects on surface tension. These chemical additives will decrease the surface tension of

the water. This allows the water to penetrate the fabric more rapidly and thoroughly.

Water is a powerful solvent that can help separate certain soils and stains from

fabrics. Some soils dissolve in water that is used to clean a garment. The mechanical

force of water flushing can also remove some soils, even though the soils themselves do

not dissolve in water.

Steaming and heating a garment also assist in separating soils and stains from a

fabric. Heat can melt or soften particles. Steam can cause particles to expand or lose their

electrostatic charges.

Finally, drying can assist in soil separation as particles curl, break or change

shape during the evaporation process. A dehydrated particle or cell is less likely to

decompose rapidly or to attract bacteria and, therefore, is less likely to generate odours.

1.2 EFFECT OF CLEAIG O FIBERS

Fibres can be divided into two groups. There are natural fibre and man-made fibre.

Each type of fibre reacts differently to the wet cleaning process. How a fibre reacts

depends on a number of factors, including strength, elasticity, dimensional stability,

absorbency and the effect of chemicals and heat. These factors have a clear influence on

the way a garment should be handled in the wet cleaning process.


3

Natural fibres include:

· Wool — when wet, it absorbs 30% of its own moisture and needs to be dried flat. It

needs to be washed gently to avoid shrinkage.

· Silk — it needs great care when washing as it becomes weak with water.

· Cotton — it can tolerate high temperatures, is strong when wet and washes well in the

washing machine. It is absorbent and wears very well, making it suitable for work wear

and soft furnishings.

· Linen — it is very strong when wet but creases easily.

Man-made fibres include:

· Nylon — it wears well and creases fall out easily. It dries quickly but is not absorbent.

· Polyester — it wears well and creases fall out easily.

· Acrylic — this fabric washes well and does not shrink. It wears well and is very light.

Fibre strength is a measure of the amount of force needed to cause a fibre to break.

It is also called tenacity, and it is measured in grams per denier. Fibre strength can change

when the fibre is exposed to water. Cotton and linen are the only fibres that get stronger

when exposed to water. Rayon and acetates are examples of fibres that get significantly

weaker in water. Polyesters and olefins, which are among the strongest of the common

fibres, do not get weaker or stronger. The strength of these fibres is not affected by water

at all. The effect of water on fibre strength is very important for the wet cleaner in the

stain removal and cleaning stages of garment care. Because the strength of fibres can

change when the fibres are wet, care must be taken when applying any force to wet fibres.

For example, rayon and acetates, since they get significantly weaker in water, could be


4

damaged by scrubbing or harsh agitation. Table 1.1 shows the wet and dry strength of

different fibres. Table 1.2 shows the resistance of different fibres to abrasion.

Table 1.1: Fibre Strength

Fibre Dry (grams/denier) Wet (grams/denier)

Acetate 1.2 - 1.5 0.8 - 1.2

Acrylic 2.0 - 3.5 1.8 - 3.3

Cotton 3.0 - 5.0 3.3 - 6.4

Linen stronger than cotton

Modacrylic 2.0 - 3.5 2.0 - 3.5

Nylon 3.0 - 6.0 2.6 - 5.4

Olefin 4.8- 7.0 4.8 - 7.0

Polyester 4.0 -5.0 4.0 - 5.0

Rayon 0.73 - 2.6 0.7 - 1.8

Silk 2.4 - 5.1 1.8 - 4.2

Wool 1.0 - 1.7 0.8 - 1.6

Table 1.2: Abrasion Resistances of Fibres

Acetate fair to low

Acrylic good to sufficient

Cotton good

Linen good but damaged by repeated flexing

Nylon good to excellent

Polyester good to excellent

Rayon poor to fair

Silk poor to fair

Wool good

1.3 HISTORY OF WASHIG MACHIE

In the early days, the most simplified hand-laundry used large amounts of time

and labour without running water, gas, or electricity. One wash, one boiling and one rinse

used about fifty gallons of water or four hundred pounds. Rubbing, wringing, and lifting


5

clothes are the washing process. Ancient peoples cleaned their clothes by pounding them

on rocks or rubbing them with abrasive sands; and washing the dirt away in local streams.

Evidence of ancient washing soap was found at Sapo Hill in Rome, where the ashes

containing the fat of sacrificial animals was used as soap.

The earliest manual washing machines imitated the motion of the human hand on

the washboard, by using a lever to move one curved surface over another and rubbing

clothes between two ribbed surfaces as in Figure 1.1. This type of washer was first

patented in the United States in 1846 and survived as late as 1927 in the Montgomery

Ward catalogue. The first electric clothes washers, in which a motor rotated the tub, were

introduced into America about 1900. All of these inventions lead up to what we use today.

Detail evolution of washing machine is attached in Appendix I.

Figure 1.1: Old Manual Washing Machine (Kessler, 2008)

Automatic washing machines became popular in the 1960s. These automate the

washing process by controlling the water and soap intake, draining and rotation of the

drum in sequence. Different types of material can be handled by using different

programmed cycles. For example, a wool wash needs a low temperature and less


6

agitation than a heavy soil cotton wash. Most automatic washing machines control the

sequence using an electromechanical cam timer, though recently fully electronic systems

based on microprocessors have become more widely available.

1.4 CLOTH CLEAIG METHOD

1.4.1 Wet Cleaning

Wet cleaning is both an old method and a new method for cleaning garments.

Water has been used to clean clothes for centuries. Inventors, scientists and engineers

have also been working for centuries to discover new methods to clean clothes quickly

and efficiently. Wet cleaning uses a wet cleaning machine, detergents, additives, stain

removal agents and a specialized dryer. Basically the process can be broken down into

stain removal, wet cleaning, drying and finishing.

1.4.2 Dry Cleaning

Dry cleaning treats garments in either perchloroethylene or petroleum.

Perchloroethylene is the solvent used in 80% of dry cleaning plants. Petroleum is used in

the remaining 20%. Dry cleaning has proven itself to be an efficient, affordable, cost

effective process for cleaning a wide variety of fibres and fabrics without causing damage

to garments. The primary drawback to dry cleaning is that perchloroethylene and

petroleum solvents are hazardous substances.


7

1.4.3 Ozone Cleaning System

The Ozonated Water Continuous Cleaning System is a new process that is still

being studied and under development stage. The theory behind the process is that ozone

(O3), working as an oxidizing agent, has the ability to disinfect, deodorize and bleach

fabrics. Ozone can be added to water, in much the same way that carbon dioxide is used

in carbonated soft drinks. Ozonated water can be combined with detergents to produce a

garment that is cleaned, disinfected and deodorized.

1.4.4 Ultrasonic Cleaning

Recent research cooperatively funded by the U.S. Department of Energy and

Kansas City Plant and Garment Care, Inc. determined that agitation for a continuous-flow,

water-based clothes washing process could be provided by ultrasound. When clothes

cleaned with ultrasound were examined, the clothes were clean enough to encourage

researchers to continue developing this process. Ultrasonic cleaning works by the

pressure of ultrasonic waves directed at the fabric through a solution of water and soaps.

The energy from the ultrasound excites the molecules of soil and causes them to separate

from the fabric.


8

1.5 STATEMET OF PROBLEM

In producing quality washing, laundry industries have main considerations which

strive to minimize time of washing, power, detergent and water consumption. In general,

washing quality could be improved by increasing the amount of washing detergent,

power, time and water used. Another issue is inefficient washing machine designs that

can affect the washing performance and hence cloth cleanliness too. Mechanical action

transmission from bottom actuator to wash contaminant cloth is lacking as consumers

commented that hand wash is still the best cleaning method.

This study aimed to determine the optimum washing result of the active washing

process which given by laboratory washing model and passive process from a

commercial washing machine. Active washing is direct squeezing force and interface

between washing liquid and cloth. Passive washing means indirect contact between

washing mechanism which is rotor and the wash load. The soil removal effect of active

washing process and passive process are compared in order to determine the best washing

process. Soil removal is measurement of cloth washer degree cleaning effect to remove

representative soils and stains from fabric.

1.6 PURPOSE

The objective of this study is to find out whether active washing process has

better washing quality compared to passive washing type. The better washing principle

should perform sufficient mechanical action on the fabrics and loosen the stain attached


9

into washing liquid to improve cleaning. Variables of the study include water speed,

washing time and radial nozzle inclination angle. The specific objectives of this study are:

a. To design and develop the laboratory active washing model.

b. To determine the degree of soil removal rate from soiled fabric for active

and passive washing process.

c. To determine the washing process which will give best cleaning effect

based on factors studied.

d. To find the significant factor that influences the washing efficiency of

active and passive washing process.

1.7 SCOPE OF THE STUDY

The study is limited to the laboratory washing model developed which is to be

compared with the commercial washing machine of model Samsung WA91U3 depicted

in Figure 1.2 and its technical specification is attached in Appendix II. The operating

procedure practiced was given by its manual (AHAM HLW-1-2006). The soil test strips

were in accordance to IEC60456. The supporting fabrics were 100% cotton. Water

hardness which indicates the amount of dissolved minerals in the water is 500 mg/l

(Ibarahim, 2006). Water temperature is taken as 30 ± 2ºC.


10

Figure 1.2: Samsung WA91U3 Washing Machine


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