1b Introduction 130417075034 Phpapp01

7/24/2019 1b Introduction 130417075034 Phpapp01

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FLUIDMECHANICS-I

INTRODUCTION (Contd)

Lecture # 01 (b)

CONTENTS OF TODAYSLECTURE

!"$%c&' roert%e$ o F'u%d$

Den$%t

Sec%*c +e%,"t

Sec%*c -o'u.e

Sec%*c ,r&/%t

Sur&ce ten$%on

CE2

En,r3 F&4&'E5&'&'

1F'u%d 6ec"&n%c$I!re&red b En,r3 F&4&'E5&'&'


2/28

D%$t%nct%on bet7een & So'%d8 F'u%d

6o'ecu'e$ o $o'%d &re u$u&'' c'o$erto,et"er t"&n t"o$e o & 9u%d3

T"e &ttr&ct%/e orce$ bet7een t"e.o'ecu'e$ o & $o'%d &re $o '&r,e t"&t& $o'%d tend$ to ret&%n %t$ $"&e3

In c&$e o 9u%d$: t"e &ttr&ct%/e orce$bet7een t"e .o'ecu'e$ &re $.&''er3

!re&red b En,r3 F&4&'E5&'&'

F'u%d 6ec"&n%c$I


3/28

D%$t%nct%on bet7een & So'%d8 F'u%d

An %de&' e'&$t%c $o'%d 7%'' deor.under 'o&d &nd once 'o&d %$ re.o/ed7%'' return to %t$ or%,%n&' $t&te3!'&$t%c $o'%d$ deor. under &ct%on o&'%ed 'o&d$ &nd deor.&t%oncont%nue$ &$ 'on, &$ 'o&d %$ &'%ed:

ro/%d%n, t"e .&ter%&' doe$ notruture3


F'u%d 6ec"&n%c$I ;

The intermolecular cohesive forces in a uiare not !reat enou!h to hol variouselements of ui to!ether" Hence a ui #illo# uner the action of sli!htest stress an

o# #ill continue as the stress is $resent"


4/28

D%$t%nct%on bet7een &


5/28



6/28



7/28

Den$%t &nd Sec%*c 7e%,"t

T"e ensit& (r"o) or mass ensit& o &9u%d %$ .&$$ er un%t /o'u.e 7"%'e t"es$eci,c #ei!ht G (,&..&)%$ %t$ 7e%,"t

er un%t /o'u.e3 Sec%*c 7t3 %$ t"e orcee?erted b ,r&/%t on un%t 7e%,"t o 9u%d3

Un%t$ o Den$%t S'u,$Ht;(3< $$te.) &ndJ,H.;(S3I $$te.)3 A'$o: c&n be e?re$$ed

&$ 'b3$ecHt2or N3$H.2

Un%t$ o Sec%*c 7e%,"t 'bHt; (3< $$te.)&nd NH.; (S3I $$te.)3


F'u%d 6ec"&n%c$I K


8/28


Den$%t %$ &b$o'ute: $%nce %tdeend$ on .&$$: 7"%c" %$%ndeendent o 'oc&t%on3

Sec%*c 7e%,"t G: on t"e ot"er "&nd%$ not &b$o'ute: $%nce %t deend$ ont"e /&'ue o ,: 7"%c" /&r%e$ 7%t"

'oc&t%on (r%.&r%' '&t%tude 8e'e/&t%on &bo/e .e&n $e& 'e/e')3

Den$%t%e$ 8 $ec%*c 7e%,"t$ o 9u%d$

/&r 7%t" te.er&ture3!re&red b En,r3 F&4&'E5&'&' F'u%d 6ec"&n%c$I


9/28


Den$%t &nd $ec%*c 7e%,"t o & 9u%d &rere'&ted &$

. / 0 1 ! 2 or 0 . 3"!

!"$%c&' =u&nt%t%e$ &re d%.en$%on&''"o.o,eneou$: t"e d%.en$%on$ o den$%t&re

In 3< S$te. M GH, ('bHt;)H(tH$)

'b3$ecHt2 .&$$H-o'3 $'u,$Hcub%c eet

In S3I S$te. M GH, (NH.;)H(.H$) N3$H.2 .&$$H-o'3 J,Hcub%c .eter


F'u%d 6ec"&n%c$I


10/28

Sec%*c 7e%,"t$ o L%=u%d$

T"e $ec%*c 7e%,"t o '%=u%d deend$onTe.er&ture (In/er$e' re'&ted)

!re$$ure (D%rect' re'&ted)

, /&'ue

!re$ence o d%$$o'/ed &%r: $&'t$ %n

$o'ut%on$ &nd $u$ended .&tter3(Incre&$e G to $'%,"t &.ount$)


F'u%d 6ec"&n%c$I 10

Un'e$$ ot"er7%$e $ec%*ed or %.'%ed b & ,%/en te.er&ture:t"e /&'ue to u$e or 7&ter %$ 45"6 l71ft8or 9":;


11/28

Sec%*c -o'u.e

T"e /o'u.e occu%ed b & un%t .&$$o 9u%d3 +e co..on' &' %t to,&$e$3

@ . ;13 . ;1Densit&

Un%t$ In 3


12/28

Sec%*c Den$%t o 9u%d /&r%e$ 7%t" te.er&ture3


F'u%d 6ec"&n%c$I 1am$le >ro7lem 5"; 5"5

>a!e? ;=(;4 (Fluid

Mechanicswith


13/28

!r&ct%ce !rob'e.$

3;31

3;3

3;3; 3;32

3;3@

3;3 3;3K


F'u%d 6ec"&n%c$I 1;

(Fluid

Mechanicswith

engineeringapplications)


14/28

Sur&ce Ten$%on

L%=u%d$ "&/e co"e$%on &nd &d"e$%on:bot" o 7"%c" &re or.$ o .o'ecu'&r&ttr&ct%on3

Cohesionen&b'e$ & '%=u%d to re$%$tTen$%'e $tre$$ 8 ahesionen&b'e$ %tto &d"ere to &not"er bod3


F'u%d 6ec"&n%c$I 12

It %$ & li%ui $ro$ert& b /%rtue o 7"%c"

orce o &ttr&ct%on ,ener&te$: &t %nter&cebet7een '%=u%d &nd & ,&$ %3e3 '%=u%d $ur&ce&nd &t t"e %nter&ce bet7een t7o%..%$c%b'e (not .%?&b'e) '%=u%d$: 7"%c"

e?ert$ & ten$%on orce %n t"e $ur&ce3


15/28

Sur&ce Ten$%on

+"en $econd 9u%d %$ not $ec%*ed &t%nter&ce: %t %$ under$tood t"&t '%=u%d$ur&ce %$ %n cont&ct 7%t" &%r3

T"e $ur&ce ten$%on /&'ue$ or '%=u%d$$'%,"t' decre&$e$ 7%t" %ncre&$%n,te.er&ture3

C&%''&r%tB %$ t"e roert oe?ert%n, orce$ on 9u%d$ b *ne tubeor orou$ .ed%&Q %t %$ due to bot"

co"e$%on &nd &d"e$%on3!re&red b En,r3 F&4&'E5&'&' F'u%d 6ec"&n%c$I 1@


16/28

Sur&ce Ten$%on

+"en co"e$%on %$ 'e$$ (t"&n&d"e$%on): t"e '%=u%d 7%'' 7et t"e$o'%d $ur&ce %n cont&ct &nd r%$e &t

t"e o%nt o cont&ct3

I co"e$%on %$ .ore: t"e '%=u%d $ur&ce7%'' dere$$ &t t"e o%nt o cont&ct3


F'u%d 6ec"&n%c$I 1

For In$t&nce: C&%''&r%t .&Je$ 7&ter rise

%n t"e ,'&$$ tube: 7"%'e .ercure$ressesbe'o7 t"e true 'e/e'3

T"e cur/ed '%=u%d $ur&ce t"&t de/e'o$ %n& tube %$ c&''ed Meniscus3


17/28


F'u%d 6ec"&n%c$I 1K

D "

A cro$$ $ect%on %n c&%''&r r%$e %n &tube 'ooJ$ '%Je &$ $"o7n %n t"e *,ure3Fro. Free body considerations:e=u&t%n, t"e '%t%n, orce$ cre&ted b

$ur&ce ten$%on to ,r&/%t orce3

Liftin! forces . +ravit& forces

rco$ r"G

" (co$) H (G3r)

+"ereQ Sur&ce ten$%on ($%,.&) %n un%t$ oorce H L

+ett%n, &n,'eG Sec%*c 7e%,"t o '%=u%dr R&d%u$ o tube" C&%''&r r%$e

6en%$cu$

C&%''&r R%$e


18/28

Sur&ce Ten$%on

T"e e?re$$%on " (co$) H (G3r) c&n beu$ed to co.ute t"e &ro?%.&te c&%''&rr%$e or dere$$%on %n t"e tube3

I t"e tube %$ c'e&n: 0 de,ree or 7&ter&nd &bout 120 de,ree$ or .ercur3

T"e e=u&t%on o/ere$t%.&te$ t"e &.ount oc&%''&r r%$e or dere$$%on: &rt%cu'&r' or

'&r,er d%&.eter tube$3 For tube d%&.eter$ '&r,er t"&n B"= inch:

c&%''&r eect$ &re ne,'%,%b'e3


F'u%d 6ec"&n%c$I 1


19/28

Sur&ce Ten$%on

Sur&ce ten$%on eect$ &re ,ener&''ne,'%,%b'e %n .o$t en,%neer%n,$%tu&t%on$3 >o7e/er: t"e c&n be

%.ort&nt %n rob'e.$ %n/o'/%n,c&%''&r r%$e3


F'u%d 6ec"&n%c$I 1

As in soil #ater one(#ithout ca$illar& mostforms of ve!eta7le life#oul $erish" Similarl&(

#hile calculatin! $ressuresan ta


20/28

Sur&ce Ten$%on

T"e$e eect$ &re &'$o %.ort&nt %n"dr&u'%c .ode' $tud%e$ 7"en t"e.ode' %$ $.&'': %n t"e bre&J u o

'%=u%d et$: &nd %n t"e or.&t%on odro$ &nd bubb'e$3

T"e or.&t%on o dro$ %$ e?tre.e'

co.'e? to &n&'4e but %$: ore?&.'e: o cr%t%c&' concern %n t"ede$%,n o %nJet r%nter$: & .u't%

b%''%ondo''&r bu$%ne$$3!re&red b En,r3 F&4&'E5&'&' F'u%d 6ec"&n%c$I 0

>a!e? 89 (FluidMechanics withengineeringapplications)

SAM>LE >'GLEM 5";B


21/28

!r&ct%ce !rob'e.$

3131

313

313; 3132

313@


F'u%d 6ec"&n%c$I 1

(Fluid

Mechanicswithengineeringapplications)


22/28

St&nd&rd At.o$"ere

F%r$t &doted %n 10$ %n USA &nd Euroeto $&t%$ need or $t&nd&rd%4&t%on o&%rcr&t %n$tru.ent$ &nd &%rcr&t

eror.&nce3 ICAO (Intern&t%on&' C%/%' A/%&t%on

Or,&n%4&t%on) St&nd&rd At.o$"ere

U$to 85


23/28

St&nd&rd At.o$"ere

U3S St&nd&rd At.o$"ere (L&$tre/%$ed %n 1K)3 Incoror&te$ ICAO&nd ISO $t&nd&rd$3 U$to :4


24/28

St&nd&rd At.o$"ere

13 Troo$"ere13 Troo$"ere


F'u%d 6ec"&n%c$I 2


25/28

-&or !re$$ure o L%=u%d$

A'' '%=u%d$ tend to e/&or&te or/&or%4e: 7"%c" t"e do b roect%n,.o'ecu'e$ %nto t"e $&ce &bo/e t"e%r

$ur&ce$3

I t"%$ %$ & con*ned $&ce: t"e &rt%&'re$$ure e?erted b t"e .o'ecu'e$

%ncre&$e$ unt%' the rate at which themolecules re-enter the liuid ! therate at which they leave: 7e c&'' t"e

/&or re$$ure &$ Saturation!re&red b En,r3 F&4&'E5&'&' F'u%d 6ec"&n%c$I @


26/28

-&or !re$$ure o L%=u%d$

At &n ,%/en te.er&ture: % t"ere$$ure on t"e '%=u%d $ur&ce &''$be'o7 t"e $&tur&t%on re$$ure: &

r&%d r&te o e/&or&t%on re$u't$:Jno7n &$ Goilin!3T"u$ 7e c&n reer to t"e $&tur&t%on

re$$ure &$ t"eGoilin! $ressure or &,%/en te.er&ture: &nd %t %$ o r&ct%c&'%.ort&nce or '%=u%d$3


F'u%d 6ec"&n%c$I

+e c&'' t"e r&%d /&or%4&t%on &nd reconden$&t%on o '%=u%d &$ %tbr%e9 &$$e$ t"rou," & re,%on o 'o7 &b$o'ute re$$urecavitation"T"%$ "eno.enon %$ oten /er d&.&,%n, &nd $o 7e.u$t &/o%d %t3


27/28

-&or !re$$ure$ o L%=u%d$

T"e /er 'o7 /&or re$$ure o.ercur .&Je$ %t &rt%cu'&r'$u%t&b'e or u$e %n &ro.eter$3


F'u%d 6ec"&n%c$I K


28/28

!re&red b En,r3 F&4&'E 5&'&'

F'u%d 6ec"&n%c$I

Documents

1b Introduction 130417075034 Phpapp01