Past Final Papers 1

8/10/2019 Past Final Papers 1

1/21

Heat and Mass Transfer/Transport Phenomena BTE 3215/ 3210

INTERNATIONAL ISLAMIC UNIVERSITY MALAYSIA

END-OF-SEMESTER EXAMINATION

SEMESTER II 2013/2014 SESSION

KULLIYYAH OF ENGINEERING

Program : ENGINEERING e!e" of #t$d% : &G 3

T'me : (:00 am ) 12:00 noon *ate : 02/05/201+

*$rat'on : 3 Hrs

,o$rse ,ode : BTE 3215/3210 #e-t'ons : 1

,o$rse T't"e : Heat and Mass Transfer/ Transport Phenomena

Th's .$est'on Paper ,ons'sts of 21Pages 'n-"$d'ng ,o!er Page 'th Eight (8).$est'ons

INSTRUCTIONS TO THE CANDIDATES

DO NOT OPEN UNTIL YOU ARE ASKED TO DO SO

There areTHREE (3) se-t'ons 'n th's $est'on paper4

Section A is omp!"sor#$ nser An#THREE (3)$est'ons from Section %4Section is

%on!s

nsers sho$"d 6e -"ear and 'nte""'g'6"e &sef$" E$at'ons4 Ta6"e and 7'g$re are atta-hed

No 6oo8s4 notes and programma6"e -a"-$"ators are perm'tted

7or spe-'f'- 'nstr$-t'ons4 p"ease refer to the appropr'ate se-t'on

Any form of Cheatn! or Attem"t to Cheat # a Sero$# O%en&e

1


2/21


'h&h may Lea( to D#m##a)*

Section A: Compulsory .

Tota" mar&s for this part ' * mar&s+

,1-

,2-

1* Mar&s+

a 9hat 's the d'fferen-e 6eteen nat$ra" -on!e-t'on and for-ed -on!e-t'on

9h'-h one 's genera""% more eff'-'ent 9h%

6 ;ne of %o$r fr'ends sa%s N$sse"t N$m6erNu's e$a" to the d'mens'on"esstemperat$re grad'ent at the s$rfa-e of a g'!en geometr% The other fr'end

sa%s 't 's the rat'o of -on!e-t'on to p$re -ond$-t'on heat transfer 9hose

s'de of the arg$ment o$"d %o$ ta8e 9h%

1* Mar&s+

a 9hat 's the d'fferen-e 6eteen "o-a" !e"o-'t% ur4x and mean !e"o-'t% um

*er'!e the e


3/21


,- 1* Mar&s+

f"at p"ate has "engthL= 3 m4 the "o-a" -on!e-t'on heat transfer -oeff'-'ent ma%6e e


4/21


Part %0 , is omp!"sor#- Anser an# To (2) !estions from .>4 .C4

.( and .10Tota" mar8s for th's part' * mar&s+

,-

,.-

(In solving problems in this part follow the

systematic approach; clearly state known, fin,

schematic, assumptions, properties, analysis an

comments.!

2* Mar&s+

Hot e5 -m 'n d'ameter and @ m "ong at a rate of 05

8g/s The s$rfa-e of the a"" 's ma'nta'ned at an a!erage temperat$re of 500

The a!erage a'r temperat$re 'n the d$-t 's 550 ,a"-$"ate the

a the Re%no"ds n$m6er

6 the -on!e-t'!e heat transfer -oeff'-'ent h

- the de-rease 'n temperat$re of the a'r as 't passes thro$gh the d$-t

(8 Mar&s)

(8 Mar&s)

( Mar&s)

( Mar&s)

( Mar&s)

( Mar&s)

+


5/21


,8-

,4-

1 Mar&s+

*r% a'r 's 'nha"ed at a rate of 10 /m'n thro$gh the tra-hea 'th a d'ameter of 20

mm and a "ength of 125 mm The 'nner s$rfa-e of the tra-hea 's at norma" 6od%

temperat$re of 3>D, and ma% 6e ass$med to 6e sat$rated 'th ater

a ss$m'ng stead%4 f$""% de!e"oped f"o 'n the tra-hea4 est'mate the mass

transfer -on!e-t'on -oeff'-'ent

6 Est'mate the da'"% ater "oss /da% asso-'ated 'th e!aporat'on 'n the

tra-hea

1 Mar&s+

,ons'der a !ert'-a" p"ate of d'mens'on 250 mm < 500 mm that 's at Ts= 13+D,'n a $'es-ent en!'ronment at TF= 20 D, 7or ea-h or'entat'on4 -a"-$"ate

a) The Ra%"e'gh n$m6er

5) The rate of heat transfer 6% -on!e-t'on from the front s$rfa-e

c) In the 'nterest of m'n'm''ng heat transfer from the p"ate4 h'-h or'entat'on 's

( 8 Mar&s)

( . Mar&s)

( Mar&s)

( Mar&s)

( Mar&s)

5


6/21


preferred 9h%

,1*-

,11-

1 Mar&s+

Ethano" 's d'ff$s'ng thro$gh a + mm stagnant f'"m of ater The ethano"

-on-entrat'ons of the entran-e and the e


7/21


S6ME SE9: E,AT;67S A7< 67STA7TS0

1- ;nterna" forced con=ection for constant s!rfacetemperat!re condition$

Therma" entr% "ength for "am'nar f"o

Graet n$m6er

am'nar4 therma" entr%4 Pr5

Ts= -onstant

HereP's per'meter P= D

9here p's the press$re drop andP's p$mp'ng poer

>

=

=

hcm

PL

TT

TT

T

T

pims

oms

i

o

e


8/21


2- ;nterna" forced con=ection

Ta8e C= 02@4 m= 0@4 and n= 03>

3- 7at!ra" on=ection for #"inder0

C

( )

3DTTgRa sD

=

( ) +1PrPrPrRe snm

DD CNu =

4k

hDNu

D= 4

A

mD

DDh!h =

( ) +1Re snm

DD !c!c!cC!h =

4AD

!c =

/ = TThA" s

04/ 44 = AsatAmA Ahn

444 satAA =

fgAs hnTThA" += /


9/21


7or Ra* 1012

4

- Heat E>changer ?7T Method

- 9ic&@s :a of imation)

(

( )

2

2>

C

1@

(

@1

Pr/55(01

3C>0@00

+

+= DDRa

Nu

4ma

Past Final Papers 1

Documents

Transcript of Past Final Papers 1