past final papers 3 hm

8/10/2019 Past Final Papers 3 hm

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INTERNATIONAL ISLAMIC UNIVERSITY MALAYSIA

END OF SEMESTER EXAMINATION

SEMESTER II 2012/2013 SESSION

KULLIYYAH OF ENGINEERING

Program : ENGINEERING Level of Study : UG3

Time : 2.30 p.m. !.30 p.m. "ate : 0!#0$#20%3

"uratio& : 3 'r

(our)e (ode :*TE 32%! Se+tio&) : % a&d 2

(our)e Title : Heat and Mass Transfer

T,i) -ue)tio& Paper (o&)i)t) of fourteen (14)Pri&ted Page) i&+ludi&g (over Page/ it,

five (5)-ue)tio&) i& Part 1 a&dfour (4)-ue)tio&) i& Part *

INSTRUCTION(S) TO CANDIDATES

DO NOT OPEN UNTIL YOU ARE ASKED TO DO SO

1ttempt All -ue)tio&) i& Part 1. Total mar) !0/

I& Part *: Q6 is Compulsory. 1&)er any Two (2)4ue)tio&) from -56 -76 -8

a&d -%0. Total mar) !0/

1&)er) ),ould 9e +lear a&d i&telligi9le.

,e&ever appropriate6 ;u)tify your a&)er.

No 9oo)6 &ote) a&d programma9le +al+ulator) are permitted.


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*TE 32%! 'eat a&d =a)) Tra&)fer

Part A:

1&)er ALL. Total mar) for Part 1 5! mar"s#

Q1 1! $ar"s#

a/ ,at i) t,e p,y)i+al )ig&ifi+a&+e of Pra&dtl &um9er> I) it po))i9le to +o&)ider Pr

a) fluid property> E?plai& ,o. (5 mar"s)

9/ (o&)ider a ,ot 9aed potato. ill t,e potato +ool fa)ter or )loer ,e& e 9lo

t,e arm air +omi&g from our lu&g) o& it i&)tead of letti&g it +ool &aturally i& t,e

+ooler air i& t,e room> E?plai& u)i&g Neto&@) la of +ooli&g. (5 mar"s)

Q2 1! $ar"s#

a/ E?plai& 9riefly t,e adva&tage) of lumped +apa+ita&+e a&aly)i) a&d t,e

+ir+um)ta&+e) u&der ,i+, t,i) i) a )uita9le approa+,. (5 mar"s)

9/ ,at are t,e +,ara+teri)ti+) of a 9la+9ody> "oe) )u+, a t,i&g a+tually e?i)t i&

&ature> ,at i) t,e pri&+ipal role of a 9la+9ody 9e,avior i& radiatio& a&aly)i)>

(5

mar"s)

Q% 1! $ar"sA

a/ Bour frie&d a))ert) t,at6 i& a ,eat e?+,a&ger6 it i) impo))i9le for t,e e?it

temperature of t,e +old fluid to 9e greater t,a& t,e e?it temperature of t,e ,ot

fluid ,e& 9ot, fluid) are )i&gle p,a)e fluid). ,at i) your re)po&)e> E?plai&

u)i&g diagram). 5 mar"s)

9/ (o&)ider air C2a&d N2/ i& a +lo)ed6 +yli&dri+al +o&tai&er it, it) a?i) verti+al

a&d it, oppo)ite e&d) mai&tai&ed at differe&t temperature). If t,e 9ottom )urfa+e

i) +older t,a& t,e top )urfa+e6 doe) ma)) tra&)fer o++ur> E?plai& u)i&g


3/14


Q5 1! $ar"s#

(o&)ider a ,emi)p,eri+al fur&a+e of diameter6 " ! m it, a flat 9a)e a) ),o& i&


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Part : Q6 is Compulsory Answer any Two (2) *uestions from

-56 -76 -8 a&d -%0.Total mar) for t,i) part+ 5! mar"s#

Q6 2! $ar"s#

1 ,ou)e 9uilt o& a river)ide i) to 9e +ooled i& )ummer 9y utiliDi&g t,e +ool ater of t,e

river6 ,i+, flo) at a& average temperature of %!H(. 1 %! m lo&g )e+tio& of a +ir+ular

du+t of 20 +m diameter pa))e) t,roug, t,e ater a) ),o& i&


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+/ if t,e emi))ivity of t,e plate i) 0.76 determi&e total ,eat tra&)fer duri&g t,i) flo.

(5 mar"s)

Q, 15 $ar"s#

1 t,i&Jalled +o&tai&er it, a ,ot pro+e)) fluid at !0 H( i) pla+ed i& 4uie)+e&t6 +old

ater pat, at %0 H( a) )o& i&


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+/ T,e +o&+e&tratio& profile a) a fu&+tio& of po)itio&xit,i& t,e li4uid film.

(5 mar"s)

ome useful e*uations an3 onstants:

%. 'eat e4uatio&

2. Stefa&J*oltDma&& +o&)ta&t !.$5%0J7#m2KF

3. T,ermal e&try le&gt, for lami&ar flo

. I&ter&al for+ed +o&ve+tio& for +o&)ta&t )urfa+e

temperature +o&ditio&6

T) +o&)ta&t

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!. Natural (o&ve+tio& for verti+al plate:


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past final papers 3 hm

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