Lab Manual 2017

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UNIVERSITI MALAYSIA SABAH

FACULTY OF ENGINEERING

CHEMICAL ENGINEERING PROGRAMME

(HK03)

L

L A

A B

B M

M A

A N

N U

U A

A LL

Semester Semester

Laboratory

WORKSHOP BLOCK E

MAKMAL SAINS HABA 2 BLOCK C

Lecturer

Dr. S.M. Ani!""#$#n

Lab. Assistants

Mr. R#"i

Mr. M!%& R!'#n

Mr. S#i!'

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T#*'+ , C,n-+n-

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N,,.. TTii--''++ PP##++

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1..00 LLaabboorraattoorryy ssaaffeettyy  !

!..00 RRee""oorrt t ##rriittiinn$ $ %%uuii&&ee''iinneess (( E/+ri$+n- E/+ri$+n- )M )M 1 1 )

)''oo* * ++eeaassuurree++eennt t uussiinn$ $ ,,eennttuurre e ++eetteerr - -)M

)M ! !

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)rriiccttiioon n ''oossssees s iin n ssttrraaii$$t t ""ii""eess 11// )M

)M  



rreessssuurre e &&rroo" " aaccrroosss s ,,aa'',,eess !!(( )M

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eennttrriiffuu$$aa' ' ""uu++" " ccaarraacctteerriissttiiccss !! )M

)M 2 2

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T#*'+ , C,n-+n-

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N,,.. TTii--''++ PP##++

1

1..00 LLaabboorraattoorryy ssaaffeettyy  !

!..00 RRee""oorrt t ##rriittiinn$ $ %%uuii&&ee''iinneess (( E/+ri$+n- E/+ri$+n- )M )M 1 1 )

)''oo* * ++eeaassuurree++eennt t uussiinn$ $ ,,eennttuurre e ++eetteerr - -)M

)M ! !

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)rriiccttiioon n ''oossssees s iin n ssttrraaii$$t t ""ii""eess 11// )M

)M  



rreessssuurre e &&rroo" " aaccrroosss s ,,aa'',,eess !!(( )M

)M / /



eennttrriiffuu$$aa' ' ""uu++" " ccaarraacctteerriissttiiccss !! )M

)M 2 2

3

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1.0 L#*,r#-,r S#+- in G+n+r#'

Tese

Tese $ui&e'ines $ui&e'ines are are +eant +eant for for safety safety a*arena*areness ess in in te te 'aboratory'aboratory.. Ho*

Ho*e,ee,er6 r6 s"s"eciecia'ia'i7e& 7e& 'ab'aboraoratortory y +a+ay y rere8ui8uire re s"s"ecieci5c 5c sasafetfety y ru'ru'es. es. %oo%oo&& +ana$e+ent of 'aboratory is

+ana$e+ent of 'aboratory is i+"ortant to "rotect 'aboratory "ersonne'9usersi+"ortant to "rotect 'aboratory "ersonne'9users a$ainst a7ar&s at *or:.

a$ainst a7ar&s at *or:.

1.1L#*,r#-,r S#+- A#r+n+ 1.1L#*,r#-,r S#+- A#r+n+

••

E,eryone is res"onsib'e for is or er o*n safety an& te safety of E,eryone is res"onsib'e for is or er o*n safety an& te safety of oters *i'e *or:in$ in te 'aboratory.

oters *i'e *or:in$ in te 'aboratory.

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Before *or:in$ *it a ce+ica'6 assess+ent +ust be +a&e of itsBefore *or:in$ *it a ce+ica'6 assess+ent +ust be +a&e of its a7ar&s an& ris:.

a7ar&s an& ris:.

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Be Be fa+fa+i'ii'iar ar *it*it  a""a""roro"ri"riate ate "r"roteotectction ion +ea+easursure e **en en you you araree *or:in$ *it te fo''o*in$;

*or:in$ *it te fo''o*in$;



 )'a++ab'e substances)'a++ab'e substances



 orrosi,e an& to<ic ce+ica'sorrosi,e an& to<ic ce+ica's



 Bioa7ar&sBioa7ar&s



 Ra&ioacti,e +ateria'sRa&ioacti,e +ateria's 

 o+"resses $aseso+"resses $ases

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Laboratory sou'& be a&e8uate'y ,enti'ate&.Laboratory sou'& be a&e8uate'y ,enti'ate&.

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e+ica' stora$e areas sou'& be coo'6 &ry6 *e'' ,enti'ate& an&e+ica' stora$e areas sou'& be coo'6 &ry6 *e'' ,enti'ate& an& a*ay fro+ sun'i$t.

a*ay fro+ sun'i$t.

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Eatin$6 &rin:in$6 an& Eatin$6 &rin:in$6 an& s+o:in$ are strict'y "roibite& in s+o:in$ are strict'y "roibite& in 'aboratories'aboratories66 as *e'' as stores an& *or:so"s.

as *e'' as stores an& *or:so"s.

1.2P+r,n#' Pr,-+-i,n 1.2P+r,n#' Pr,-+-i,n

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Laboratory coat6 safety $o$$'es an& $'o,es =if nee&e&> sou'& beLaboratory coat6 safety $o$$'es an& $'o,es =if nee&e&> sou'& be *orn a'' te ti+e in te 'aboratory.

*orn a'' te ti+e in te 'aboratory.

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A'A'*a*ays ys asassusurre e ttat at yoyou u *a*as s yoyour ur aan&n&s s bebefoforre e 'e'ea,a,inin$ $ ttee 'aboratory.

'aboratory.

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SoSort rt s:s:irtirts6 s6 sosorts rts an& an& o"eo"en?tn?toe& oe& ssoesoes9sa9san&an&a's 's sosou'& u'& not not bebe *orn in te 'aboratory to a,oi& s:in e<"osure.

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1.3Fir+ H#"#r& #n& H#"#r&,! C%+$i#' 1.3Fir+ H#"#r& #n& H#"#r&,! C%+$i#'

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A'*ays store @a++ab'e 'i8ui&s in a""ro"riate safety cabinets9cans.A'*ays store @a++ab'e 'i8ui&s in a""ro"riate safety cabinets9cans.

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3o not store inco+"atib'e rea$ents to$eter6 e.$. @a++ab'es an&3o not store inco+"atib'e rea$ents to$eter6 e.$. @a++ab'es an&

aci&

aci&s. s. Se$rSe$re$ate aci&s e$ate aci&s an& an& basbases6 es6 an& an& corcorrosrosi,e i,e +ate+ateria'ria's s frofro++ or$anic an& @a++ab'e +ateria's.

or$anic an& @a++ab'e +ateria's.

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##ear ear a""ra""ro"rio"riate ate "r"rotecotecti,e ti,e e8ui"e8ui"+ent +ent suc suc as as 'abo'aboratoratory ry coatcoat66 a"ron6 $'o,es an& eye "rotection $ear *en you are *or:in$ *it a"ron6 $'o,es an& eye "rotection $ear *en you are *or:in$ *it @a++ab'e6 corrosi,e an& to<ic ce+ica's.

@a++ab'e6 corrosi,e an& to<ic ce+ica's.

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Ensure tat no i$nition sources "resent nearby *i'e *or:in$ *itEnsure tat no i$nition sources "resent nearby *i'e *or:in$ *it @a++ab'e ce+ica's.

@a++ab'e ce+ica's.

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A'' e'ectrica' cor&s sou'& a'*ays be in $oo& con&ition. E'ectrica'A'' e'ectrica' cor&s sou'& a'*ays be in $oo& con&ition. E'ectrica' out'ets sou'& be $roun&e&.

out'ets sou'& be $roun&e&.

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3o not store eters for 'on$ "erio&s to a,oi& for+ation e<"'osi,e3o not store eters for 'on$ "erio&s to a,oi& for+ation e<"'osi,e "ero<i&es.

"ero<i&es.

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ororrorosi,si,e e cce+ie+icaca's 's can can buburn rn an& an& irirritritate ate tistissusue. e. If If inina'a'e& e& oror in$este&6 it +ay aect 'un$ an& sto+ac tissue.

in$este&6 it +ay aect 'un$ an& sto+ac tissue.

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AA,oi,oi& & +i<+i<inin$ $ oo<i&<i&i7ii7in$ n$ cece+i+ica'ca's s *it*it  ototer er cece+i+ica'ca's s &ur&urin$in$ &is"osa'.

&is"osa'.

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ararefuefu' ' *e*en n &ea&ea'in'in$ $ *it*it  carcarcincino$eo$ens ns =ca=cancencer r cacausiusin$ n$ a$ea$ent>nt>.. Sus"

Sus"ecte& carciecte& carcino$eno$ens ns ="'ea="'ease se ceccec: : for for a a fu'fu'' ' 'ist'ist>; >; c'oc'ororoforfor+6+6 ben

ben7i&7i&ineine6 6 beben7en7ene6 ne6 +et+ety'y'c'c'ororo+o+etety' y' eteter6 er6 ,in,iny' y' cc'or'ori&ei&e66 acry'onitri'e6 for+a'&ey&e6 etc.

acry'onitri'e6 for+a'&ey&e6 etc.

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Ne,er use 'ubricants on ,a',e re$u'ators of co+"resse& $ases.Ne,er use 'ubricants on ,a',e re$u'ators of co+"resse& $ases.

1.4L#*,r#-,r

1.4L#*,r#-,r H,!+5++H,!+5++inin

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A'' e8ui"+ent sou'& be ins"ecte& carefu''y before use&.A'' e8ui"+ent sou'& be ins"ecte& carefu''y before use&.

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E8ui"+ent an& *or: benc +ust be E8ui"+ent an& *or: benc +ust be c'eane& after use.c'eane& after use.

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Use non?cro+ate c'eanin$ so'ution if "ossib'e. Ma:e sure c'eanin$Use non?cro+ate c'eanin$ so'ution if "ossib'e. Ma:e sure c'eanin$ is &one in te fu+e oo& if su'"uric aci& $'ass c'eaner is use&.

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•

ee" 'aboratory @oor &ry at a'' ti+es. Any s"i''s +ust be i++e&iate'y atten&e& to.

1.6A-+r H,!r7L,n H,!r

E/+ri$+n-•

A,oi& e<"eri+enta' *or: in an unoccu"ie& s"ace9bui'&in$ if "ossib'e.

•

A'*ays "'ace a note sou'& any unatten&e& e<"eri+ents +ust be carrie& out6 statin$ te e<"eri+ent6 na+e of researcer9stu&ent an& contact nu+ber.

•

A'*ays cec: tat @a+es an& co+"resse& $as su""'ies are sut o *en not in use an& en& of &ay.

1.8E$+r+n Pr,+&!r+

•

A'' 'aboratory "ersonne'9users +ust be fa+i'iar *it te 'ocation an& uses of te safety &e,ices in an& aroun& te 'aboratory6 for e<a+"'e;

 Safety so*er  )u+e oo&

 )ire e<tin$uiser  )irst ai& :it

 Eye *as station

 )ire a'ar+

•

ontact te 'aboratory "ersonne' or Uni,ersity safety o4cer i++e&iate'y *en e+er$ency a""ens.

•

U"on in$estion of ce+ica's6 if ,icti+ is a*a:e6 $i,e *ater. If nauseate&6 &o not $i,e @ui&s. If unconscious6 R +i$t be nee&e&.

•

U"on ina'ation of a7ar&ous ce+ica's6 +o,e te ,ictio+ out for

fres air. erfor+ arti5cia' res"iration if ,icti+ is not breatin$.

•

)or ce+ica' s"i''s; =i> aci& s"i''s C a""'y neutra'i7er or a&& *ater if necessary an& cec: +i<ture *it in&icator for neutra'i7ationD =ii> so',ent s"i''s C a""'y acti,ate& carcoa' an& +i< torou$'y unti'

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+ateria' is &ry. Transfer +i<ture into "'astic ba$6 tie u" an& 'abe'6 "'ace in fu+e oo&. ontact 'aboratory "ersonne' for &is"osa'.

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2.0 R+,r- Wri-in G!i&+'in+

Your 'aboratory re"ort sou'& contain te fo''o*in$s; C,9+r #+

 Na+e  Matric nu+ber of te stu&ent  Na+e of e<"eri+ent

 3ate of e<"eri+ent  %rou" nu+ber

1.0 In-r,&!-i,n ('i$i- -, 3 #+ $#/)

 FbGecti,e of te e<"eri+ent

 Bac:$roun& +ateria' C e<istin$ 5n&in$s an& teories re'e,ant to your stu&y

 3escri"tion of s"ecia'i7e& e8ui"+ent

 usti5cation of e<"eri+ents i+"ortance

2.0 M+-%,&,',

 E8ui"+ent6 a""aratus an& +ateria'

 roce&ure

 3escribe te "rocess in crono'o$ica' or&er C e<"'ain a'' ste"s in te or&er tey actua''y a""ene&6 not as tey *ere su""ose& to a""en

3.0

R+!'- Resu't

 'ear9concise su++ary of te co''ecte& &ata  Re"orts of &ata an& teir ana'ysis

 Tab'e  )i$ure

 Sou'& a'' be tit'e&  Labe' c'ear'y

 Inc'u&e so+e e<"'anatory te<t &escribin$ *at &ata a""ears in

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 Fbser,ation

4.0 Di!i,n

 Inter"ret te resu'ts of te e<"eri+ent an& &iscuss teir +eanin$  Your &iscussion re'ates te resu'ts to te issues raise& in te

intro&uction

 o+"are e<"ecte& resu'ts *it tose obtaine&

 E<"'ain your resu'ts in ter+s of teoretica' issues

 Re'ate resu'ts to your e<"eri+ent obGecti,e  Ana'y7e any e<"eri+enta' error

6.0 C,n'!i,n

 Ans*er te "rob'e+ state& in te tit'e an& intro&uction

 Base your conc'usion on your resu'ts

R++r+n+

 Laboratory +anua'

 Any outsi&e rea&in$

A+n&i+

 Ra* &ata6 ca'cu'ation6 $ra"6 "icture95$ure6 tab'e tat a,e not been inc'u&e& in te re"ort =+a:e sure you refer to eac a""en&ices at 'east once in your re"ort>

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FLUID MECHANICS LABORATORY E:PERIMENT 1 FLOW MEASUREMENT USING ;ENTURI METER

1.0 INTRODUCTION

Venturi +eter is use& to +easure te @ui& @o* rate by re&ucin$ te cross sectiona' area in te @o* "at6 $eneratin$ a "ressure &ierence. It +a:es use of Bernou''is rinci"'e6 a restate+ent of te 'a* of onser,ation of Ener$y as a""'ie& to te @ui& @o*.

In tis e<"eri+ent6 te ussons (!!J Venturi Meter is use& in conGunction *it te In'et Hea& Tan: (10 an& te (10/ Variab'e Hea& Fut'et Tan:. Te (10( +ano+eter boar& is re8uire& for "ressure +easure+ent. Te )ee&bac: (102 +ay be use& instea& of te in'et ea& tan: to increase te @o* ran$e.

Te ,enturi6 *ic is +anufacture& fro+ trans"arent acry'ic +ateria'6 fo''o*s te c'assic !1K ? 10K con,er$ent?&i,er$ent &esi$n *ic for+s te basis of +ost en$ineerin$ stan&ar&s for ,enturi @o* +eters. Te (!!J co+"'ies *it te Britis Stan&ar& BS10/! for @o* +easure+ent. Te &i+ensions of te Venturi Meter are so*n in )i$ure 1.1. Te u"strea+ an& troat "ressure ta""in$s are use& for @o* +easure+ent *i'st te &o*nstrea+ ta""in$s a''o*s an assess+ent of te "ressure reco,ery to be +a&e. Te troat &ia+eter is 10++ an& te u"strea+ an& &o*nstrea+ "i"e &ia+eters are bot !1++.

)i$ure1.1 3i+ensions of ussons (!!J Venturi +eter.

1.1 THEORIES AND E:PLANATION

)i$ure1.! 3ia+eters an& &ierentia' "ressure across ,enturi +eter at section 1  !.

P

1 P2

D₁ D

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Refer to )i$ure 1.!6 fro+ consi&eration of continuity bet*een te +out of te ,enture at section 1 an& te troat at section !;

2 2 1 1V A V A Q = = _=1.1>

an& on te intro&ucin$ te &ia+eter ratio   3! 9 316 ten

2 1 2 1 2 V V A A

=

β =1.!> A""'yin$ Bernou''is teore+ to te ,enture +eter bet*een section1 an& section!6 ne$'ectin$ 'osses an& assu+in$ te ,enturi is insta''e& ori7onta''y g V g P g V g P 2 2 2 2 2 2 1 1

+

=

+

ρ ρ =1.> Rearran$in$6 g V V H g P P ρ ρ 2 1 2 2 2 1

−

=

−

=1./>

an& so',in$ for V!6

4 2 2 2 1 2 1 2 1 2 1 ) ( 2 β ρ

−

=













−

=

g H V V P P V =1.2> =1.(>

Te ,o'u+etric @o* rate is ten $i,en by

4 2 2 2 1 2 β − = =_A_V _A g H Q =1.J> Te actua' &iscar$e *i'' be 'ess tan tis &ue to 'osses causin$ te ,e'ocity trou$ te troat to be 'ess tan tat "re&icte& by

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e<"eri+enta''y &eter+ine& coe4cient of &iscar$e &. Te actua'

&iscar$e *i'' ten be $i,en by;

4 2 1 2 β − =_C _A g H Q _d =1.-> *ere =1.>

Te coe4cient of &iscar$e ,aries *it bot te Reyno'&s nu+ber an& area ratio. Ty"ica''y ,a'ues for a +acine& ,enturi +eter are bet*een 0.J2 an& 0.2.

Te "ressure 'oss across te ,enture +eter is 'ess tan te "ressure &ierence +easure& bet*een te +out an& te troat &ue to te "ressure reco,ery *ic occurs in te &i,er$ence as te :inetic ener$y is re&uce&.

1.2 OB<ECTI;ES

1. To ca'cu'ate te coe4cient of &iscar$e fro+ e<"eri+enta' &ata for a ,enturi +eter.

!. To in,esti$ate te +easure+ent of ,o'u+etric @o*rate usin$ a ,enturi +eter.

1.3 E=UIPMENT PREPARATION

In'et (10 onstant Hea& In'et Tan: *it o,er@o* "i"e e<tension 5tte&.

Test Section ussons (!!J Venturi +eter Fut'et (10/ Variab'e Hea& Fut'et Tan: Mano+eter T*o of te sin$'e +ano+eter tubes.

1.4 E:PERIMENTAL PROCEDURE

1. Set u" te a""aratus as "er instructions in F"eration a"ter.

!. Start te "u+" an& estab'is a *ater @o* trou$ te test section. . Ensure tat any air bubb'es are b'e& fro+ te +ano+eter tubes. /. Ne<t6 raise te *ater @o* rate unti' 1 +_9r.

2. #ait unti' te *ater 'e,e' in te in'et an& out'et of +ano+eter stabi'i7e&.

(. Recor& te rea&in$ for te in'et an& out'et.

J. Re"eat ste" ?( for @o* rate of 0.6 0.-6 0.JOO unti' 0.1 +_9r.

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3ia+eter of ,enturi +out  PPPPPP ++ 3ia+eter of ,enturi troat  PPPPPP ++

F',r#-+ (L7$in) M#n,$+-+r In'+- ($) M#n,$+-+r O!-'+- ($) S#$' + (L) Ti$+ () 1 !  A,era$ e 1 !  A,era$e ! !! !1 !0 1 1-1J 1( 12 1/ 1 1! 11 OBSER;ATIONS>

1.8 RESULTS AND ANALYSIS

1. Recor& te resu'ts on a co"y of te resu'ts seet. !. a'cu'ate ,o'u+etric @o* rate for eac resu't.

. 'ot $ra" of @o* rate a$ainst te s8uare root of te ea& an& &ra* te best strai$t 'ine fro+ te ori$in trou$ te resu'ts. a'cu'ate te s'o"e an& &eter+ine te coe4cient of &iscar$e for te ,enturi +eter.

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Quantities of *ater co''ecte&6 Q =L> Ti+e to co''ect

*ater6 t =s>

Vo'u+e @o* rate6 Q =L9+in> In'et ea&6 H1 =+> Fut'et ea&6 H! =+> Venturi &ierentia' ea&6 H =H1?H!> =+> Venturi &ierentia' ea&6 =H>19! Area of ,enturi troat6 A! =+!>=10? /_> Ve'ocity at ,enturi troat6 V! =+9s> Q6 ,o'u+etric @o* rate =A!V!> Actua' &iscar$e6 &

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FLUID MECHANICS LABORATORY E:PERIMENT 2 FRICTION LOSSES IN STRAIGHT PIPES

2.0 INTRODUCTION

Te "ressure 'oss a'on$ a "i"e is cause& by friction an& can$es in ,e'ocity or &irection of @o*. In or&er to 5n& te friction 'oss in "i"es6 te @ui& friction +easure+ents a""aratus are s"ecia''y &esi$ne& to a''o* te &etai'e& stu&y of te @ui& friction ea& 'osses *ic occur6 *en an inco+"ressib'e @ui& @o*s trou$ "i"es6 ben&s6 ,a',es an& oter "i"e @o* +eterin$ &e,ices. )riction ea& 'osses in strai$t "i"es of &ierent si7es can be in,esti$ate& o,er a ran$e of Reyno'&s Nu+ber. Te friction factors &e"en& on te Reyno'&s nu+ber of te @o* an& te

"i"e re'ati,e rou$ness.

ussons (!!0 La+inar )'o* A""aratus use& in tis e<"eri+ent consists of a tubu'ar test section of  ++ interna' bore an& 20-++ 'on$6 inc'u&in$ a 1 ++ be'' nose entry6 *ic is su""orte& insi&e a "rotecti,e outer !2 ++ tube an& is ter+inate& at eac en& in buse& unions. Besi&es tat6 t*o test sections of ussons (!!1 Losses In i"es an& )ittin$s A""aratus are use& in tis e<"eri+ent6 i.e. te J ++ no+ina' bore "i"e an& te 10 ++ no+ina' bore "i"e *it t*o static "ressure ta""in$s (0 ++ a"art6 eac /(/ ++ 'on$. It is inten&e& tat te test section sou'& be +ounte& bet*een te (10 onstant Hea& In'et Tan: an& te(10/ Variab'e Hea& Fut'et Tan:. Te (10( Mano+eter Boar& is use& to +easure te ea& 'oss across te tubu'ar test section.

2.1.1 F', in i+

If @ui& @o*s &o*n a "i"e at 'o* ,e'ocities it is foun& tat in&i,i&ua' @ui& "artic'es fo''o* @o* "ats *ic are "ara''e' but tose "artic'es nearer te centre of te "i"e +o,e faster tan tose near te *a''. Tis ty"e of @o* is :no*n as 'a+inar @o* or strea+ 'ine @o*. At +uc i$er ,e'ocities it is foun& tat secon&ary irre$u'ar +otions are su"eri+"ose& on te +o,e+ent of te "artic'es an& a si$ni5cant a+ount of +i<in$ ta:es "'ace6 te @o* is sai& to be turbu'ent. Fsbourne Reyno'&s in,esti$ate& tese t*o &ierent ty"es of @o* an& conc'u&e& tat te "ara+eters *ic *ere in,o',e& in te @o* caracteristics *ere;

 Te &ensity of te @ui& $ +?

V Te ,e'ocity of te @ui& + s?1

3 Interna' &ia+eter of "i"e +  Te abso'ute ,iscosity of te Ns +?!

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@ui&

Reyno'&s *as ab'e to so* tat te caracter of te @o* cou'& be &escribe& *it te ai& of a &i+ension'ess "ara+eter6 *ic is no* :no*n as Reyno'&s nu+ber6

Re 

µ ρ VD

=!.1>

)'ui& +otion *as foun& to be 'a+inar for te ,a'ues of Re be'o* !000 an& turbu'ent for ,a'ue Re $reater tan /000. 3ierent 'a*s of @ui& resistance a""'y to 'a+inar an& turbu'ent @o*s.

)or 'a+inar @o* it is foun& tat te "ressure &ro" or ea& 'oss is "ro"ortiona' to ,e'ocity an& tat tis can be re"resente& by oiseui''es e8uation for te y&rau'ic $ra&ient

2 32 gD V L h i f ρ µ

=

=!.!>

)or turbu'ent @o* te re'ationsi" bet*een ea& 'oss an& ,e'ocity is e<"onentia'

f  Vn =!.>

an& a'tou$ tere is no si+"'e e8uation for turbu'ent @o* it is acce"te& en$ineerin$ "ractice to use an e+"irica' re'ationsi" for te y&rau'ic $ra&ient *ic is attribute& to 3arcy an& #eisbac

i  g D fV L h_f 2 4 2

=

=!./>

*ere f is an e<"onentia''y &eter+ine& friction factor *ic ,aries *it bot Reyno'&s nu+ber an& te interna' rou$ness of te "i"e. A &ierent friction factor +ay be use& *ic is four ti+es 'ar$er tan te friction factor in te 3arcy?#eisbac for+u'a.

2.1.2 N+-,n? L# , ;i,i-

#en a 'ayer of @ui& is +o,e& 'atera''y re'ati,e to an a&Gacent 'ayer6 a force is set u" *itin te @ui& *ic is in o""osition to te searin$ action. Tis interna' resistance :no*n as te abso'ute ,iscosity of te @ui& is cause& by +o'ecu'ar a&esion an& acts a'on$ te co++on boun&ary of te @ui& 'ayers. In te SI syste+ abso'ute ,iscosity is &e5ne& as te force in Ne*ton *ic *ou'& "ro&uce unit ,e'ocity in a "'ate of unit area at unit &istance fro+ a "ara''e' stationary "'ate6 tat is

y V ∂ ∂ − = _σ µ _=!.2>

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Te unit of ,iscosity is in te c$s syste+ is te "oise . A +easure of te W@ui&ity of a substance is te :ine+atics ,iscosity *c is &e5ne& as;?

=!.(> i.e. X 

ρ µ

=!.J> 2.1.3 L#$in#r F', in # Cir!'#r Pi+

onsi&er te @o* of @ui& in a concentric in a circu'ar "i"e as so*n in 5$ure. Let te "ressure &ro" &ue to @ui& friction o,er a "i"e 'en$t L be .

)i$ !.1Strea+tube in a ircu'ar i"e

Te force e<erte& by te &ierentia' "ressure on te @ui& containe& in te strea+ tube in te &irection of te @o* is $i,en by

 Z &!₉ _/ _=!.->

F""osin$ tis force is a sear force create& by te ,iscous resistance to @o* *ic is "ro"ortiona' to te sear stress an& te *ette& area of te strea+tube

[ Z &L =!.> )or &yna+ic e8ui'ibriu+ tese t*o forces +ust ba'ance

 Z &!_{9 /  [ Z &L} =!.10> 4 d L P

⋅

∆

=

σ =!.11>

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4 0 d L P

⋅

∆

=

σ =!.1!> An& substitute for δ P δ / L bac: into te e8uation $i,es

t cons D d tan 0 = = σ σ =!.1>

)ro+ *ic it fo''o*s tat te sear stress ,aries 'inear'y fro+ 7ero at te centre to a +a<i+u+ at te "i"e *a''.

Te sear stress is re'ate& to ,e'ocity by Ne*tons 'a* of ,iscosity r V δ δ µ σ

=

−

=!.1/> E8uatin$ tese t*o e<"ressions for sear stress

= − r V δ δ µ 4 d L P

⋅

∆

=!.12> Re"'acin$ & by !r µ δ δ 2 r r V = L P ∆ ∆ =!.1(> In,esti$atin$ fro+ te "i"e centre =r  0> to te "i"e *a'' =r  R an& V  0> yie'&s µ 4 2 2 _r R V

=

−

L P ∆ ∆ =!.1J> Te ,e'ocity &istribution is terefore "arabo'ic *it +a<i+u+ ,e'ocity at te centre of te "i"e

µ 4 2 max R V = L P ∆ ∆ µ 16 2 D = L P ∆ ∆ =!.1->

An& te +ean ,e'ocity is a'f of te +a<i+u+ ,e'ocity

µ 32 2 D V mean = L P ∆ ∆ =!.1> Rearran$in$6

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2 32 D LV P

=

µ mean

∆

_=!.!0>

E<"ressin$ te "ressure 'oss as a ea& &ue to friction6 Hf o,er

te "i"e 'en$t ';

2 32 gD LV f mean ρ µ = ∆ =!.!1> Te ea& 'oss "er unit 'en$t of "i"e

L h_f

*ic is :no*n as te y&rau'ic $ra&ient6 sy+bo' Wi6 is ten $i,en by

=

L h i f 2 32 gD V _mean ρ µ =!.!!>

*ic is :no*n as oiseui''es e8uation for 'a+inar @o*. Note tat V is no* ta:en to si$nify te +ean ,e'ocity.

2.1.4 T!r*!'+n- F', in Cir!'#r Pi+

Te ,e'ocity &istribution of turbu'ent @o* across "i"e is +ore unifor+ tan te "arabo'ic ,e'ocity &istribution of 'a+inar @o*. onsi&er a section of "i"e 'en$t L o,er *ic te "ressure &ro" is 6 as so*n in 5$ure !.!.

)i$ !.! Turbu'ent )'o* in ircu'ar i"e

Te forces actin$ on te cy'in&er of @ui& are te "ressure forces "ro&ucin$ te @o* an& te o""osin$ sear forces cause& by frictiona' resistance at te *a''.

4 / 2 D P LD π π σ _ο

=

∆

=!.!> 4 L PD ∆ = ο σ =!.!/>

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No* acce"tin$ tat te sear stress is "ro"ortiona' to te s8uare of te +ean ,e'ocity

[  V! _=!.!2> ten6 2 KV

=

σ =!.!(> *ere  is a constant.

E8uatin$ tese t*o e<"ressions for sear stress

2 4 . D KV L P

=

∆

=

σ =!.!J> D KLV P 2 4 = ∆ =!.!->

E<"ressin$ te "ressure 'oss as a ea& 'oss &ue to friction6 f

f  gD KLV ρ 2 4  D fL 4 g V 2 2 =!.!> *ere f  2 K _ρ is te 3arcy friction factor.

Te a'ternati,e &e5nition of friction factor is often so*n as f =f &as> an& te ea& 'oss e8uation is ten *ritten as

f  g V D L f 2 ' 2 =!.0> 2.1.6 R+n,'& n!$*+r

#en Reyno'&s "'otte& te resu'ts of is in,esti$ation of o* te ener$y ea& 'oss ,arie& *it te ,e'ocity of @o*6 e obtaine& t*o &istinct re$ions se"arate& by a transition 7one.

In te 'a+inar re$ion te y&rau'ic $ra&ient is &irect'y "ro"ortiona' to te +ean ,e'ocity. In te turbu'ent @o* re$ion te y&rau'ic $ra&ient is "ro"ortiona' to te +ean ,e'ocity raise& to so+e "o*er n ,a'ue of n bein$ in@uence& b te rou$ness of te "i"e *a''.

i  V1.J _{)or s+oot "i"e}

i  V! _{)or ,ery rou$ "i"e}

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2.1.8 Fri-i,n #-,r

Te ea& 'oss &ue to friction for bot 'a+inar an& turbu'ent @o* can be "resicte& by te 3arcy #eisbatc e8uation

2 32 gD V i ρ µ = =!.1> By +u'ti"'yin$ to" an& botto+ by V an& rearran$in$

g V VD i 2 16 4 2 ρ µ × = or g V VD i 2 64 2 ρ µ = =!.!> g V D f i 2 4 2 = or g V D f i 2 ' 2 = =!.> *ere e R VD f

=

16

=

16 ρ µ or e R VD f '

=

64

=

64 ρ µ =!./> are as to be use& &ue to tese t*o &ierent &e5nitions of te friction factor6 *ic are bot in e8ua''y co++on use6 an& terefore in coosin$ te a""ro"riate re'ationsi" bet*een te friction factor an& te ea& 'oss. #en usin$ $ra" of friction factor a$ainst Reyno'&s nu+ber a'*ays cec: te re'ationsi" for 'a+inar @o* as a +ean of &istin$uisin$ bet*een te t*o.

If e R f

=

16 ten use g D fLV h f 2 4 2

=

=!.2> If e R f '= 64 ten use g D LV f h_f 2 ' 2

=

=!.(> )or turbu'ent @o* te friction factor is a function of Reyno'&s nu+ber6 te re'ati,e rou$ness of te "i"e *a''ε /D. )or i$'y turbu'ent @o*s te friction factor beca+e in&e"en&ent of te Reyno'&s nu+ber in a @o* re$i+e :no*n as fullydeveloped turbulent ow. Te +ost *i&e'y acce"te& &ata for friction factors for use *it te 3ar'ey #eisbac: for+u'a is tat "ro&uce& by rofessor L.).Moo&y.

Se'ection of "i"e si7e for a "i"e to carry a $i,en @o* rate6 *ic is a ,ery co++on e<ercise6 is +a&e easier if te re'ationsi" bet*een te ea& 'oss an& "i"e &ia+eter is :no*n for s"eci5c case of constant @o* rate.

)or a $i,en @o* rate6 te +ean ,e'ocity In te "i"e is $i,en by; V D Q 2 π

=

ence V 4Q •

=

_=!.J>

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Substitutin$ for V into oiseui''es e8uation for 'a+inar @o* 2 2 2 4 2 4 2 4













=

D Q g D f g D fV L h i f π ence i α 4 1 D =!.->

An& usin$ te 3arcy?#eisbac e8uation for turbu'ent @o*

2 2 2 4 2 4 2 4













=

D Q g D f g D fV L h i f π ence i α 5 1 D =!.>

Te ea& 'oss is terefore in,erse'y "ro"ortiona' to te &ia+eter of te "i"e raise to te fort "o*er for 'a+inar @o* an& in,erse'y "ro"ortiona' to te 5ft "o*er for turbu'ent @o*.

2.2 OB<ECTI;ES

1. To in,esti$ate te "ressure 'oss &ue to friction in a "i"e. !. To co+"are te re'ationsi" bet*een te friction factor an&

Reyno'&s nu+ber *it e+"irica' &ata.

In'et Initia''y (10 onstant Hea& In'et Tan: *it o,er@o* "i"e e<tension 5tte&.

Test Section

(!!1 Losses in i"e J ++ an& 10 ++ test section. Fut'et (10/ Variab'e Hea& Fut'et Tan:.

Mano+eter T*o of te sin$'e +ano+eter tubes.

Asse+b'y Ensure te be'' +oute& entry en& of te (!!0 test section is at te 'eft an& en& an& tat is correct'y inserte& into te in'et tan:. Ensure tat te (!!1 J ++ bore test section is insta''e& te correct *ay roun& *it te conica' in'et at te 'eft an& en&.

1. Start te "u+" an& estab'is a *ater @o* trou$ te test section. Raise te s*i,e' tube of te out'et tan: so tat it is c'ose to te ,ertica'.

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!. A&Gust te benc re$u'atin$ ,a',e =or "u+" s"ee&> to "ro,i&e a s+a'' o,er@o* fro+ te in'et tan: an& o,er@o* "i"e. Ensure tat any air bubb'es are b'e& fro+ te +ano+eter tubes.

. Set u" a seria' of @o* con&itions *it &ierentia' ea&s startin$ at !2++ in ste"s of !2++ u" to 120++ an& tereafter in ste"s 20++ u" to a +a<i+u+ of 200++. At eac con&ition carefu''y +easure te @o* rate usin$ te ,o'u+etric tan: an& a sto" *atc. /. Measure te *ater te+"erature.

2. Re"ort te test *it te oter test sections.

2.6 RESULTS SHEET

1. Test Section 3ia+eter OO..++ #ater Te+"erature OOO \  onstant Hea& In'et Tan: OOO.++ Variab'e Hea& Fut'et Tan: Quantity of *ater o''ecte&6 Q =Litres> Ti+e to o''ect #ater6 t =sec> In'et Hea&6 H1=++> Fut'et Hea& H!=++>

!. Test Section 3ia+eter OO..++ #ater Te+"erature OOO \ 

onstant Hea& In'et Tan: OOO.++ Variab'e Hea& Fut'et Tan: Quantity of *ater o''ecte&6 Q =Litres> Ti+e to o''ect #ater6 t =sec> In'et Hea&6 H1=++> Fut'et Hea&

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OBSER;ATIONS>

2.8 RESULTS AND ANALYSIS>

1. Recor& te resu'ts on a co"y of te resu'ts seet.

!. 3eter+ine te *ater &ensity an& ,iscosity fro+ Anne< 1 of art 1 of te +anua'.

. )or eac resu't ca'cu'ate te +ean ,e'ocity an& ence te Reyno'&s nu+ber an& friction factor ] ’ .

/. 'ot a $ra" of 'o$^ f a$ainst 'o$^ V6 &ra* a strai$t 'ine trou$

te resu'ts an& +easure its s'o"e to e<"ress te re'ationsi" bet*een f an& V in te fro+ f  Vn.

2. Fn a "otoco"y of te $ra" on "a$es  C 12 "'ot te "oints of friction factor a$ainst Reyno'&s nu+ber.

(. )ro+ te $ra" of fraction factor a$ainst Reyno'&s nu+ber on "a$e  ?12 &eter+ine te e+"irica' friction factor ] usin$ te Reyno'&s nu+ber for eac resu't an& assu+in$ a "i"e rou$ness of

0.0012++.

1. Test Section 3ia+eter;OOOOO++ #ater Te+"erature;OOOOO.O. \  3ensity;OOOOOOOO.. :$9+! Viscosity;OOOOOOOOO.c Quantity of #ater o''ecte&6 Q ='itre> Ti+e to o''ect #ater6 t =sec>

Vo'u+e )'o* Rate6 Q ='itres9+in> Mean Ve'ocity6 V =+9sec> Lo$e V Reyno'&s Nu+ber6 Re Lo$e Re In'et Hea&6 H1 =++> Fut'et Hea&6 H! =++>

)riction Hea& Loss6 f

=++> =H1?H!>

Lo$e f

)riction )actor6 f Lo$e f

!. Test Section 3ia+eter;OOOOO++ #ater Te+"erature;OOOOO.O. \ 

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3ensity;OOOOOOOO.. :$9+! Viscosity;OOOOOOOOO.c Quantity of #ater o''ecte&6 Q ='itre> Ti+e to o''ect #ater6 t =sec>

Vo'u+e )'o* Rate6 Q ='itres9+in> Mean Ve'ocity6 V =+9sec> Lo$e V Reyno'&s Nu+ber6 Re Lo$e Re In'et Hea&6 H1 =++> Fut'et Hea&6 H! =++>

)riction Hea& Loss6 f

=++> =H1?H!>

Lo$e f

)riction )actor6 f Lo$e f

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APPENDI:

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FLUID MECHANICS LABORATORY E:PERIMENT 3 PRESSURE DROP ACROSS ;AL;ES

3.0 INTRODUCTION

ressure &ro" is a critica' e'e+ent in ,a',e si7in$ an& ,a',e se'ection. Te +ost critica' factors to &eter+ine te "ressure &ro" are te ori5ce si7e an& interna' @o* "at.

Tere are ,arious ty"es of ,a',es *ic can be use& to contro' te @ui& @o*. Ho*e,er6 &ierent ty"es of ,a',es a,e teir o*n @o* caracteristics. Te @o* caracteristics an& @o* rate are in@uence& by te &e$ree of ,a',e o"enin$. Te &esi$n of "i"in$ an& "u+"in$ syste+s for ce+ica'6 "ar+aceutica' an& foo& "rocessin$ in&ustries re8uires :no*'e&$e of te "ressure &ro" &ue to @o* in strai$t "i"e se$+ents an& trou$ ,a',es an& 5ttin$s. resence of ,a',es an& 5ttin$s *i'' cause friction 'osses. Tese usua''y resu't fro+ &isturbances of te @o*6 *ic is force& to can$e &irection abru"t'y to o,erco+e "at obstructions an& to a&a"t itse'f to su&&en can$es in te cross section or sa"e of te &uct.

Va',es fa'' into t*o broa& ty"es6 'inear an& rotary. In a 'inear ,a',e suc as a $'obe ,a',e te &is: 'ifts fro+ te seat. Te &is: rotates in te seat of a rotary ,a',e suc as a ba'' ,a',e. In tis e<"eri+ent6 ussons (!!1 Test Section *it ba'' ,a',e is use& to &eter+ine te "ressure &ro". In $enera'6 ba'' ,a',e as a s"erica' ba'' *it a ori7onta' bore. Te ba'' ,a',e uti'i7es te sa+e conce"t as te "'u$ ,a',e an& is so+eti+es referre& to as te Ws"erica' "'u$ ,a',e or Wba'' "'u$ ,a',e.

3.1.1 Pr+!r+ L, Ar, ;#'9+ #n& ;#'9+ C%#r#-+ri-i Te "ressure &ro" across a ,a',e is &e"en&ent on te ty"e an& construction of te ,a',e6 its si7e an& te &e$ree of ,a',e o"enin$. 3ierent ty"es of ,a',es *ic +ay a,e te sa+e @o* ca"acity *en fu''y o"en +ay e<ibit ,ery &ierent caracteristics. In&ustria' "ractice6 "articu'ar'y in connection *it contro' ,a',es6 is to state bot te ,a',e ca"acity an& te @o*?o"enin$ caracteristics of te ,a',e in ter+s of a @o* coe4cient. In te U an& te USA te @o* coe4cient is :no*n as , *i'st in continenta' Euro"e a &ierent @o* coe4cient6 :, is

co++on'y use&. Te @o* coe4cients are a'' &e5ne& as te @o* rate *ic *i'' "ass trou$ te ,a',e *en unit "ressure &ierentia' is a""'ie& across te ,a',e. Te ,arious units *ic are use& for @o* coe4cients are so*n in te tab'e.

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, =USA>

:, =Euro"e>

US %a''ons 9 +in ubic +eters 9 our

oun& 9 inc!

$ 9 c+!

Te @o* trou$ a ,a',e in ter+s of te @o* coe4cient for a "ressure &ro" _ across te ,a',e is $i,en by

S P C Q V ∆ = =.1>

*ere S is te s"eci5c $ra,ity. Rearran$in$;

2 2 v C SQ P

=

∆

=.!>

an& e<"ressin$ te "ressure 'oss as a ea& of @ui&

2 2 v v gC SQ h ρ

=

=.>

an& assu+in$ tat te s"eci5c $ra,ity is 1.0 ten

2 2 2 2 2 v v v gC V A gC Q h ρ ρ

=

=./>

No* intro&ucin$ a ,a',e 'oss coe4cient6  , *ic sou'& not be

confuse& *it te Euro"ean for+ of te ,a',e @o* coe4cient6 :,.

g V K h_v _v 2 2 = =.2>

E8uatin$ tese t*o e<"ressions for te ,a',e ea& 'oss yie'&s;

2 1 v v C K α _=.(>

tat is te ,a',e 'oss coe4cient  , is in,erse'y "ro"ortiona' to te

s8uare of te @o* coe4cient.

Va',e @o* caracteristics are nor+a''y "resente& as tab'es or $ra"s of ,a',e @o* coe4cient a$ainst "ercenta$e ,a',e o"enin$. Tere are t*o "articu'ar ,a',e caracteristics *ic are i+"ortant.

a> Linear in *ic ,  `.

b> E8ua' ercenta$e in *ic ,  `!. Te i+"ortance of

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"ro"ortiona' increase in ,a',e o"enin$ causes te sa+e "ro"ortiona' increase in @o* "ro,i&in$ te "ressure across te ,a',e re+ains constant. )or e<a+"'e6 if a ,a',e as a , of (/ at -0 o"enin$ an& an e8ua' "ercenta$e

caracteristic6 ten at /0 o"enin$ te , *i'' be (/ <

=/09-0>!_{ 1(. If te ,a',e o"enin$ is can$e& fro+ /0}

to /16 te , ,a',e *i'' increase fro+ 1( to 1(=/19/0>! 

1(.-16 tat is a 2.0(!2 increase. If te ,a',e o"enin$ at -0 is increase& to -! te , ,a'ue *i'' increase fro+ (/

to (/=-!9-0>!_{ (J.!/6 tat is a 2.0(!2 increase in @o*.}

c> Quic: Actin$ in *ic a 'ar$e increase in @o* ca"acity is acie,e& for a s+a'' initia' o"enin$ of te ,a',e.

)i$ure .1 Re'ationsi" $ra" bet*een @o* coe4cient an&  of ,a',e o"enin$

3.2 OB<ECTI;E

To in,esti$ate te "ressure &ro" across ,a',es an& te @o* caracteristics of ,a',es.

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In'et (10 onstant Hea& In'et Tan: *it o,er@o* "i"e e<tension 5tte&

Test Section (!!1 Test Section *it ba'' ,a',e Fut'et (10/ Variab'e Hea& Fut'et Tan: Mano+eter T*o of te sin$'e +ano+eter tubes

Asse+b'y Ensure te test sections are insta''e& te correct *ay roun&

1. Before startin$ te "u+"6 o"erate te ,a',e trou$ its fu'' ran$e of +o,e+ent an& estab'is6 usin$ a "rotractor for te ba'' ,a',e6 a &atu+ "osition an& +eans of +easurin$ te &e$ree of ,a',e o"enin$.

!. )u''y o"en te ,a',e in te test section. Start te "u+" an& estab'is a *ater @o* trou$ te test section. Raise te s*i,e' tube of te out'et tan: so tat it is c'ose te ,ertica'.

. A&Gust te benc re$u'atin$ ,a',e =or "u+" s"ee&> to "ro,i&e a s+a'' o,er@o* fro+ te in'et tan: an& o,er@o* "i"e. Ensure tat any air bubb'es are b'e& fro+ te +ano+eter tubes.

/. Set u" a @o* con&ition *it a &ierentia' ea& of 20++. arefu''y +easure te @o* rate usin$ te ,o'u+etric tan: an& a sto" *atc. 2. arefu''y c'ose te ,a',e in s+a'' but +easurab'e incre+ents6 unti'

te ,a',e is fu''y c'ose&. Recor& te ,a',e "osition an& +easure te @o* rate at eac ,a',e "osition.

(. Measure te *ater te+"erature.

3.6 RESULTS SHEET

#ater Te+"erature OOOOOO. \  3ensity OOOOO.:$9+!

Viscosity OOOO.. c Test Section 3ia+eter OOO++

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Quantity of *ater o''ecte&6 Q

='itres>

Ti+e to o''ect #ater6 t =sec> Vo'u+e )'o* Rate6 Q ='itres9+in> Mean Ve'ocity6 V =+9sec> Ve'ocity Hea&6 V !_{9!$ =+>} In'et Hea&6  1 =++> Fut'et Hea&6  ! =++>

i"e )riction Loss6   =++>

Va',e )riction Loss6  V =+> Va',e ressure Loss6  =a> Va',e )'o* oe4cient6  V =$"+9"si19!> Va',e F"enin$6 &e$rees =°> Va',e F"enin$6 t ercent => OBSER;ATION>

1. Recor& te resu'ts on a co"y of te resu't seet.

!. 3eter+ine te *ater &ensity an& ,iscosity fro+ Anne< 1 of art 1 of te +anua'.

. a'cu'ate te ,e'ocity an& ence te ,e'ocity ea& for eac resu't. /. )ro+ te resu'ts for te 10++ "i"e use& in e<"eri+ent !6 or by

ana'ysis6 ca'cu'ate te ea& 'oss   for a (0 ++ strai$t 'en$t of

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e<"eri+ent ! ten correct te resu'ts for any &ierence in te &ia+eter of te t*o test sections = α 1932_>.

2. a'cu'ate te "ressure 'oss across te ,a',e an& &eter+ine te ,a',e @o* coe4cient for eac resu't6 con,ert te @o* coe4cient to a "ercenta$e of te @o* coe4cient for te fu''y o"en ,a',e.

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Gauge pressure Vauum !tm"sp#er$ ( %ar"meter Pressure Pressure) !&s"'ute er" !&s"'ute pressure

FLUID MECHANICS LABORATORY E:PERIMENT 4 CENTRIFUGAL PUMP CHARACTERISTICS

4.0 INTRODUCTION

A si+"'est for+ centrifu$a' "u+" consists of an i+"e''er rotatin$ *itin a casin$ an& so+e for+ of ousin$ *it a centra' in'et an& a "eri"era' out'et. It raises te "ressure of a 'i8ui& by $i,in$ it a i$ :inetic ener$y. Te :inetic ener$y is ten con,erte& to inGection *or: ="ressure>.

In tis e<"eri+ent6 sin$'e centrifu$a' "u+" is use& for &iscar$in$ *ater into te *eir canne'. Te "u+" caracteristics can be stu&ie& trou$ te tota' ea&?&iscar$e caracteristic6 y&rau'ic "o*er an& te e4ciency of a centrifu$a' "u+". 3eter+inin$ te +ost e4cient "u+" is ,ita' in or&er to +ini+i7e ener$y consu+"tion6 as *e'' as to +ini+i7e cost an& ener$y consu+"tion.

4.1.1 Pr+!r+ #n& H+#&

4.1.1.1 A-$,%+ri Pr+!r+

At+os"eric "resure is te ratio bet*een te *ei$t of te at+os"ere "er unit area on te eart surface. Tere are se,era' base for +easurin$ "ressure as "er be'o*

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Zero atmospheric pressure is te "ressure at *ic air is re+o,e& creates at ,acuu+. Tis "ressure is ca''e& ABSFLUTE ERF. Any "ressure +easure& on tese bases is ca''e& ABSFLUTE RESSURE. Tus one at+os"eric "ressure is e8ua' to 101.!2 :i'o Ne*ton "er s8uare +eter =:N9+!_{> or 1/.J "oun& "er s8uare inc. Since baro+eter}

is use& to +easure at+os"eric "ressure6 tis "ressure is often referre& to as Baro+eter "ressure6 b.

%enera''y "ressure +easurin$ &e,ice +easure "ressure &ierence fro+ tat of at+os"eric. Te resu'tin$ "ressure is ca''e& %au$e "ressure6 $ *ic can be "ositi,e or ne$ati,e ,a'ue. Tus6

Abso'ute "ressure  Baro+eter ressure  %au$e ressure abs  b  a =/.1>

Te at+os"eric "ressure or baro+eter "ressure can be in&icate& by

b  101 C 0.1022EL =/.!> *ere b is te at+os"eric "ressure in +i'ibar

Fne +i'ibar e8ua' 0.01/2 "oun& "er s8uare inc or e8ua' to *ater co'u+n at /o_{ of 0.0101J+.}

EL is te e'e,ation of abo,e +ean seas 'e,e' for te "oint to be +easure&.

In "u+" insta''ation ca'cu'ations6 te at+os"eric "ressure +ay be e8uate& to a *ater co'u+n ei$t as;

H"  10. C 0.001-EL =/.>

H" is te at+os"eric "ressure e<"resse& at ei$t of *ater

co'u+n at /o_{ in +eter.}

4.1.1.2 Pr+!r+ H+#&6 =H>

Instea& of nor+a' "ressure unit of force "er area suc as Ne*ton "er s8uare +eter =N9+!_{> or "oun& "er s8uare inc =SI> 'i8ui&}

"ressure is often in&icate& as ei$t of co'u+n creatin$ "ressure on te co'u+n su""ortin$ surface. Tis ei$t of 'i8ui& co'u+n is ca'' ressure Hea&.

Tus H"  9d  9$ =/./>

*ere d  s"ecific *ei$t   Li8ui& &ensity

$  Acce'eration &ue to $ra,ity

H"  =N9+!>  =:$9.-1N>  =+9 d:$>

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4.1.1.3 ;+',i- H+#&6 =H9>

Any 'i8ui& +o,in$ in a "i"e or o"en canne' as a ,e'ocity6 ence :inetic ener$y. Tis ener$y +ay be e<"resse& as ea& of 'i8ui& ,e'ocity.

H,  V!9 !$ =/.2>

*ere V  Li8ui& ,e'ocity

H,  =V!>+!9s!  =19!$> s!9+

 =V!_{9!$> +}

Ve'ocity ea& +ay be &e5ne& as a ei$t fro+ *ic 'i8ui& +ay fa'' &ue to $ra,ity an& attains a ,e'ocity e8ua' to te ,e'ocity of @ui& @o*.

4.1.1.4 S-#-i H+#&6=H>

In te "u+" o"eration6 ener$y is a&&e& to te 'i8ui& *en it @o*s fro+ one "oint to anoter at i$er e'e,ation. ressure *ic +ay be e<"resse& as 'i8ui& co'u+n at te "u+" suction an& &iscar$e *ere is no @ui& @o* is ca''e& static ea&.

)i$ure /.! Static Hea&

Hei$t of 'i8ui& co'u+n abo,e "u+" center'ine on te &iscar$e si&e of te "u+" is ca''e& Static 3iscar$e Hea&.

Hei$t of 'i8ui& co'u+n abo,e "u+" center'ine =5$ure b> on te "u+" suction is ca''e& Static Suction Hea&. If te 'i8ui& 'e,e' on te "u+" suction si&e is 'o*er tan center'ine6 ten ei$t is ca''e& Static Suction Hea&.

Tota' Static Hea& is te a'$ebraic &ierence bet*een Static 3iscar$e Hea& an& Static Suction Hea&. Tis tota' Static Hea& is te

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+ini+u+ ea& tat "u+" +ust e<ert to te @ui& before any @o* occurs.

4.1.1.6 Fri-i,n H+#&6 =H >

#en 'i8ui& @o*s fro+ one "oint to te ne<t suction si&e of te "u+" to &iscar$e si&e6 tere is a s+a'' ea& 'oss &ue to fricton? bet*een 'i8ui& an& "assa$e *a''. Tis is ca''e& )riction Hea&.

)i$ure /. )riction Hea&

Te ,a'ues of te abo,e 'osses &e"en& on te @o*. Te i$er te @o* rate6 te i$er te 'oss. Terefore6 &urin$ "u+" o"eration te Actua' Tota' Suction Hea& to Static Suction Lift "'us )riction Hea& fro+ 1 to 2. If te 'i8ui& 'e,e' on te suction si&e is i$er tan center'ine of te "u+" Tota' Suction Hea& e8ua' Static Suction Hea& +inus Tota' )riction on te suction si&e.

Si+i'ar'y6 on te &iscar$e si&e6 te su+ of a'' friction 'osses fro+ ( to  is te Tota' )riction Hea& on te &iscar$e si&e. Te Tota' 3iscar$e Hea& tus e8ua' Static Hea& "'us )riction Hea& on te &iscar$e si&e.

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4.1.1.8 T,-#' H+#& , F'!i&6=HT>

Tota' ea& at any "oint of te 'i8ui& is te su+ of a'' ea&s at "oint.

Tota' Hea&  ressure Hea&  Ve'ocity Hea&  Static Hea& H T  H"  H,  Hs

 9 d  V!_9!$__ _=/.(>

In case no ener$y is ta:en in or out of te ! "oints6 te &ierence bet*een H Tis )riction Hea&.

)riction Hea& bet*een oint 1 an& !

Hf1!  HT1 C HT!  19 d C !9 d  V1!9!$ C V!!9!$  1 C ! =/.J>

In te case of a "u+"6 an ener$y is e<erte& to te @ui& bet*een 1 an& !. Te &ierence bet*een HT!an& HT1 is te "u+" tota'

ea& or Tota' 3yna+ic Hea& =H T3>.

H T3  H T1 C H T!  = ! C 1>9 d  =V!! C V1!>9!$  =!?1> =/.->

If friction is consi&ere&6 H T3  H T1 C H T!  Hf1!

= ! C 1>9 d  =V!! C V1!>9!$  =!?1>  Hf1! =/.>

4.1.2 P,+r #n& P!$ E@i+n.

o*er is te a+ount of *or: &one "er unit ti+e. Tis unit +ay be in #atts =N?+9s>. Fne Horse o*er e8ua' J/2.J #atts or 220ft?'b9s. In "u+" o"eration6 *e consi&er ! ty"es of "o*er.

4.1.2.1 P,+r ,!-!- , P!$ (W,)

Tis is "o*er tat "u+" &e'i,ers to te 'i8ui& an& often referre& to as Hy&rau'ic o*er or #ater o*er. Hy&rau'ic o*er &e"en& on te rate of @o* =Q> an& ea& =H T3> or "ressure =>.

#o Q or QH T3 =/.10>

If #o is te 'i8ui& "o*er in #atts

Q is te )'o* rate in 't9+in  is te "ressure in :$9c+! f kg N m cm cm kg P L m L Q W 1 81 . 9 10 1000 1 se 60 m$n 1 m$n 2 2 4 2 3 0 = × × × × ×

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 1.(2 Q  #atts. =/.11>

4.1.2.2 P,+r In!- -, -%+ P!$ (Wi)

Tis is te "o*er tat is &e'i,ere& to te "u+" by +o,er suc as +otor or en$ine so tat te "u+" can &e'i,er "o*er to te 'i8ui&. Tis in"ut "o*er can be +easure& by a &yna+o+eter.

#i  )r  !Zn =/.1!>

*ere #i  o*er In"ut #atts

)  3yna+o+eter turnin$ force :$ R  3yna+o+eter ar+ 'en$t + n  ri+e +o,er s"ee& r"+ Tus se 60 m$n 1 1 81 . 9 ) ($m 2 m$n

×

=

f f i kg N rev ensionless rad rev n rm kg W π  1.0!JJ)+ =N?+>9sec  1.0!JJ)+ #atts =/.1>

Increase of &yna+o+eter tor8ue =T)r> is +easure& &irect'y by an in&icator to rea& in N?+ se 60 m$n 1 ) ($m 2 m$n

×

−

=

rev ensionless rad rev n m !N W _i π  0.10/J( Tn =N?+>9sec  0.10/J( Tn #atts =/.1/> In"ut "o*er to te =an& a'so to te in,erter> can be +easure& by a *att+eter.

4.1.2.3 P!$ Eii+n (P)

u+" e4ciency  o*er tat "u+" &e'i,ers to 'i8ui& 9 In"ut "o*er

  #o 9 #i =/.12>

Note ; If a *att +eter is use&6 te *att+eter *i'' in&icate& +otor in"ut not "u+" in"ut6 ence te e4ciency beco+es "u+"? +eter e4ciency not "ure e4ciency.

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To &eter+ine te tota' ea&?&iscar$e caracteristics6 y&rau'ic "o*er an& e4ciency of a centrifu$a' "u+";

i> #it constant su""'y ,o'ta$e ii> At constant s"ee&.

u+"

Arran$e+e nt

Sin$'e centrifu$a' "u+" &iscar$in$ into te *eir

canne'. If te Au<i''iary u+" (101 is 5tte& o"erate te iso'atin$ ,a',es as so*n.

#att+eter Essentia' for +easure+ent of e'ectrica' "o*er in"ut for "u+" e4ciency test6 connect as so*n in )i$ure  on "a$e 1?1/.

u+" S"ee& 3is"'ay Unit

Not essentia' for constant su""'y ,o'ta$e e<"eri+ent6 but usefu' to +easure "u+" s"ee&. Essentia' for constant

s"ee&

tests6 connect as so* in )i$ure  on "a$e 1?1/.

4.4.1 C,n-#n- S!' ;,'-#+

1. Start te "u+" fo''o*in$ te stan&ar& startin$ "roce&ure. !. 3urin$ tis e<"eri+ent a&Gust te "u+" @o* by usin$ te

beac re$u'atin$ ,a',e.

gA--n; 3o not use te ,ariab'e S"ee& ontro' Unit to a&Gust te @o*rate or to correct any can$es in "u+" s"ee&h

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. Start te test *it te re$u'atin$ ,a',e fu''y c'ose&. Recor& te "u+" suction an& &e'i,ery "ressures an& te "u+" s"ee&.

/. artia''y o"en te re$u'atin$ ,a',e to a''o* te "u+" to "ro&uce a &iscar$e @o* *it a "u+" &iscar$e "ressure so+e 2 to 10 'ess tan te initia' test 5$ure.

2. Measure te @o* rate by eiter ta:in$ te ti+e ta:en to co''ect a suitab'e ,o'u+e of *ater in te +easurin$ tan:6 or by usin$ te Rota+eter.

(. Recor& te "u+" suction "ressure6 te "u+" &e'i,ery "ressure6 te @o* rate an& te "u+" s"ee&.

J. )urter rea&in$s are ta:en for "u+" ea&s at a""ro<i+ate'y e8ua' incre+ents of "u+" &iscar$e "ressure unti' te beac re$u'atin$ ,a',e is fu''y o"en.

4.4.2 C,n-#n- P!$ S++&

1. Start te "u+" fo''o*in$ te stan&ar& startin$ "roce&ure. !. 3urin$ tis e<"eri+ent a&Gust te "u+" @o* by usin$ te

benc re$u'atin$ ,a',e an& use te u+" S"ee& ontro' Unit to correct any can$es in "u+" s"ee&6 ensurin$ te correct "u+" is se'ecte& on te (10! u+" S"ee& 3is"'ay Unit. Tis a''o*s te "u+" s"ee& to be +aintaine& at te re8uire&

constant ,a'ue.

. Start te test *it te re$u'atin$ ,a',e fu''y c'ose& an& a "u+" s"ee& of (0 re,9sec. Recor& te "u+" suction an& &e'i,ery "ressures an& te "u+" s"ee&.

/. artia''y o"en te re$u'atin$ ,a',e to a''o* te "u+" to "ro&uce a &iscar$e @o* *it a "u+" &iscar$e "ressure so+e 10 to !0 'ess tan te initia' test 5$ure.

2. A&Gust te u+" S"ee& ontro' Unit to +aintain te "u+" s"ee& of -0 re,9sec. Measure te @o* rate by eiter ta:in$ te ti+e ta:en to co''ect a suitab'e ,o'u+e of *ater in te +easurin$ tan:6 or by usin$ te Rota+eter.

(. Recor& te "u+" suction "ressure6 te "u+" &e'i,ery "ressure6 te @o* rate an& te "u+" s"ee&.

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J. )urter rea&in$s are ta:en for "u+" ea&s at a""ro<i+ate'y e8ua' incre+ents of "u+" &iscar$e "ressure unti' te beac re$u'atin$ ,a',e is fu''y o"en.

-. Re"eat te test for "u+" s"ee& of 0 re,9sec.

4.6 RESULTS SHEET

C,n-#n- S!' ;,'-#+ Quantity of *ater

co''ecte&6 Q ='itres> Ti+e to co''ect *ater6

t =sec> u+" 1 In'et "ressure6 1 =bar> u+" 1 Fut'et "ressure6 ! =bar> u+" 1 S"ee&6 =Re,9sec> u+" 1 E'ectrica' In"ut o*er6 #i =#atts> C,n-#n- S++& i. C,n-#n- S!' (0 r+97+) Quantity of *ater co''ecte&6 Q ='itres> Ti+e to co''ect *ater6

t =sec> u+" 1 In'et "ressure6 1 =bar> u+" 1 Fut'et "ressure6 ! =bar> u+" 1 E'ectrica' In"ut o*er6 #i =#atts> ii. C,n-#n- S!' (0 r+97+) Quantity of *ater co''ecte&6 Q ='itres> Ti+e to co''ect *ater6

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t =sec> u+" 1 In'et "ressure6 1 =bar> u+" 1 Fut'et "ressure6 ! =bar> u+" 1 E'ectrica' In"ut o*er6 #i =#atts> OBSER;ATION>

1. Resu'ts sou'& be recor&e& on a co"y of te sin$'e "u+" test seet. !. If te ,o'u+etric +easurin$ tan: *as use& ten ca'cu'ate te

,o'u+e @o* rate fro+;

Q  Q9t

orrect te "ressure rise +easure+ent across te "u+" by a&&in$ 0.0J bar o a''o* for te &ierence of 0.J1/ + in ei$t bet*een te +easure+ent "oint for te "u+" out'et "ressure an& te actua' "u+" out'et connection. Ten ca'cu'ate te +ano+etric ea& fro+;

H+  =!?1>9ρ$

a'cu'ate te y&rau'ic "o*er fro+; #  ρ$ H+Q

An& ca'cu'ate te o,era'' e4ciency fro+; η0  #9#i

. 'ot te "u+" caracteristics as a sin$'e $ra" of +ano+etric ea& a$ainst ,o'u+etric @o* rate for te resu'ts of te constant s"ee& test an& te constant ,o'ta$e test.

/. 'ot a $ra" of y&rau'ic "o*er an& o,era'' e4ciency a$ainst @o* rate for eac set of resu'ts. If re8uire& tis $ra" can be use& for inter"o'ation to "ro,i&e ,a'ues to enab'e constant y&rau'ic "o*er an& constant e4ciency to be &ra*n onto te "u+" caracteristics. C,n-#n- S!' ;,'-#+

Quantity of *ater co''ecte&6 Q ='itres> Ti+e to co''ect *ater6

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t =sec>

Vo'u+e )'o* Rate Q ='itres9+in> u+" 1 In'et "ressure6 1 =bar> u+" 1 Fut'et "ressure6 ! =bar> u+" 1 S"ee&6 =Re,9sec> u+" 1 E'ectrica' In"ut o*er6 #i =#atts> u+" 1 Mano+etric Hea&6 H+ =+eter> u+" 1 Hy&rau'ic o*er6 # =#atts> u+" 1 F,era'' E4ciency6 η0 => C,n-#n- S++& i. C,n-#n- S!' (0 r+97+) Quantity of *ater co''ecte&6 Q ='itres> Ti+e to co''ect *ater6

t =sec>

Vo'u+e )'o* Rate Q ='itres9+in> u+" 1 In'et "ressure6 1 =bar> u+" 1 Fut'et "ressure6 ! =bar> u+" 1 S"ee&6 =Re,9sec> u+" 1 E'ectrica' In"ut o*er6 #i =#atts> u+" 1 Mano+etric Hea&6 H+ =+eter> u+" 1 Hy&rau'ic o*er6 # =#atts> u+" 1 F,era'' E4ciency6 η0 => ii. C,n-#n- S!' (0 r+97+) Quantity of *ater

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Ti+e to co''ect *ater6 t =sec>

Vo'u+e )'o* Rate Q ='itres9+in> u+" 1 In'et "ressure6 1 =bar> u+" 1 Fut'et "ressure6 ! =bar> u+" 1 S"ee&6 =Re,9sec> u+" 1 E'ectrica' In"ut o*er6 #i =#atts> u+" 1 Mano+etric Hea&6 H+ =+eter> u+" 1 Hy&rau'ic o*er6 # =#atts> u+" 1 F,era'' E4ciency6 η0 =>

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FLUID MECHANICS LABORATORY E:PERIMENT 6 DETERMINATION OF COEFFICIENT OF ORIFICE METER

6.0 INTRODUCTION

An Fri5ce @o* +eter is te +ost co++on ea& ty"e @o* +easurin$ &e,ice. An ori5ce "'ate is inserte& in te "i"e'ine an& te &ierentia' "ressure across it is +easure&. Te ori5ce "'ate inserte& in te "i"e'ine causes an increase in @o* ,e'ocity an& a corres"on&in$ &ecrease in "ressure at te ,enacontracta. )ro+ te @o* "attern6 @ui& &iscar$e ,e'ocities an& corres"on&in$ coe4cients can be esti+ate&. Te coe4cient of ,e'ocity6 V6 is te ratio of te actua' ,e'ocity to te

teoretica' ,e'ocity. Te coe4cient of &iscar$e6 &6 is te ratio of te

actua' @o* rate to te teoretica' @o* rate. 6.1 THEORIES AND E:PLANTION

C,+@i+n- , 9+',i-

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At a 'e,e' H abo,e te ori5ce6 ,e'ocity of *ater &iscar$e trou$ te ori5ce is V  √!$H. Tis ,e'ocity consists of ori7onta' an& ,ertica' co+"onents. As air resistance is ne$'i$ib'e6 ,e'ocity V can be consi&ere& as constant.

At te sa+e ti+e6 te Get "at is &ro""in$ &ue to $ra,ity startin$ fro+ 7ero ,e'ocity at te ori5ce.

Vertica' ,e'ocity6 U =+9sec >  $t =2.1> Acce'eration &ue to $ra,ity6 $  .-1 +9sec!

=2.!>

Vertica' &istance6 Y =+>   Ut   $t!

=2.>

y  0 *en te botto+ en& of te nee&'e is at te sa+e 'e,e' te center of te ori5ce. Te y  0 +ar: is +a&e on te "ane' bein& te nee&'e near te to" en& of te 5rst nee&'e.

)or tis e<"eri+ent6 *e assu+e te Get "at touc te "robes at "oint 16 ! 6 OO- res"ecti,e'y.

Hori7onta' &istance fro+ 0?1  j1

0?!  j! etc Vertica' &istance 0?1  Y1 0?!  Y! etc )ro+ Y   $t! t  √=!Y9$> t1  √=!Y19$> t!  √=!Y!9$>

At te sa+e ti+e j1  Vt1

j!  Vt! etc

t1  j19V √=!Y19$>

V  j19√=!Y19$>

Y16 Y! can be +easure& fro+ te $ra" =ti"s of "robe 1 an& !>.

Tis actua' ,e'ocity V at "oint 1 =V1> can be foun&. Si+i'ar'y6 V!6

V +ay be foun&.

oe4cient of Ve'ocity6 ,  Actua' Ve'ocity9Teoretica'

Ve'ocity

Tus6 ,1 V19V =j19√=!Y1>=!$H>9$>>  j19!√ Y1HD V!  j!9!√ Y!H

=2./>

Various , +ay be foun& by ,aryin$ *ater 'e,e' in te tan: as

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#ater is &irecte& to te benc +easurin$ tan: or a +easurin$ cu". Tus @o* rate can be &eter+ine& by ti+in$.

Teoretica' @o* rate6 Q  VA =2.2>

Teoretica' ,e'ocity6 V  √!$H +9sec =2.(>

Fri5ce cross section area6 A  π&!_{9/ +}!

=2.J>

3ia+eter of te ori5ce6 3  / ++ or - ++ =2.-> Let actua' @o* rate fro+ +easure+ent  QA

Te coe4cient of &iscar$e6 &  QA9Q  QA9=π&!9/.√!$H> =2.>

It *i'' be foun& fro+ te e<"eri+ent tat QA is 'ess tan Q. Tis

is because of te contraction of te &ia+eter of te Get after "assin$ trou$ te ori5ce. Tis is :no*n as VENA FNTRATA *ic *i'' be foun& at &istance of one a'f te ori5ce &ia+eter on*ar&.

By ,aryin$ *ater 'e,e' in te tan: or can$in$ ori5ce si7e6 ,arious & +ay be foun&.

6.2 OB<ECTI;E

To stu&y te @o* trou$ ori5ce i.e. ,e'ocity coe4cient an& &iscar$e coe4cient an& actua' Get "ro5'e +ay be co+"are& *it tat of teory.

'ear acry'ic tan: !0 c+ &ia+eter < /- c+ i$. #ater in'et is at te botto+ of te tan: *ic as sti''in$ +ateria's to s+ooten te @o*. Le,e' sca'e is attace& to te si&e of te tan:.

An o,er @o* "i"e can a&Gust *ater 'e,e' in te tan: to as i$ as /! c+ fro+ te center of te ori5ce. #ater fro+ o,er@o* sou'& be &irecte& to te stora$e tan:.

Te sar" e&$e& ori5ce is attace& to an& @usin$ *it te si&e of te tan:. T*o ori5ces are "ro,i&e&  ++ an& ( ++ &ia+eter.

A *ite boar& *it - "robes is attace& ne<t an& ,ertica''y "ara''e' to te tan: *a'' an& "er"en&icu'ar to te Get "at. Te "robes are at a &istance of 26 106 126 !06 !26 26 an& /0 c+ fro+ te ori5ce. A $ra" "a"er can be attace& to te to" of te boar& to recor& te 'e,e' of ti" of te "robe. =A'' "robe 'en$ts are e8ua'>. Hence ti"s of "robes at to" or botto+ "ro,i&e te sa+e "roGecti'e.

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+easure+ent of @o* rate.

1. Insta'' te re8uire& ori5ce.

!. A&Gust te o,er@o* "i"e to obtain a re8uire& 'e,e' in te tan:.

. F"en te *ater su""'y ,a',e to obtain a stea&y @o* *it +ini+u+ o,er@o*.

/. #ait unti' *ater 'e,e' in te tan: an& Get "ro5'e is stab'e before a&Gustin$ te "robes ti"s to be in 'ine *it te center of te Get an& recor& te "robe ti"s "ro5'e =u""er ti"s> as *e'' as y0 +ar:.

2. Recor& te @o* ,o'u+e by usin$ a sto" *atc an& te benc +easurin$ tan: or a +easurin$ cu".

6.6 RESULTS SHEET E<"eri+ent No. 1 !  / 2 ( J #ater 'e,e' H =++> Vo'u+e ='it> Ti+e =sec>

)'o* rate ='it9+in> 3istance fro+ $ra" =++> j1  206 Y1  j!  1006 Y!  j  1206 Y  j/  !006 Y/  j2  !206 Y2  j(  006 Y(  jJ  206 YJ  j-  /006 Y-  oe4cient of Ve'ocity V1 V! V V/ V2 V( VJ

(49)

V

-oe4cient of 3iscar$e

&