PENGUKURAN
PANAS
JENIS, KBNDUKTIVITAS
PANAS
BUAW
APEL MALANC
( q a l u d d i l w e s e r i aMill.
DAhlraM RANGKA PENENTLIAN NlLAl DlFLDSBVITAS PAHAS
OIeh
TEDDY
KUSWARDANA
F
24.0892
1992
FAKULTAS TEKNOLOGI
PERTANIAN
INSTITUT PERTANIAN
BOGOR
~ d i d a p a t s l s r i p e n e l i t i s n d i a t a s , dengar1 r . i i a i - n i l s i
y a n g t e l a l i d i k e t a h u i s e b e l u m n y a .
U n t u k m e n e n t u k a n p a n a s j e n i s d i g u n a k a n m e t o d e
p e n c a m p u r a - n ( m e t h o d o f m i x t u r e s ) , y a i t u d i g u n a k a n
persamaa.n k e s e i m b a n g a n p a n a s a n t a r a b a h a n d a n s i s t e n
k a l o r i m e t e r , d i m a n a p a n a s y a n g d i b e r i k a n o l e h b a h a n
sama d e n g a n p a n a s y a n g d i t e r i m a o l e h s i s t e m k a l o r i m e -
t e r . I J n t u k m e n e n t u k a n k o n d u k t i v i t a s p a n a s d i g u n a k a n
a l a t C o n d u c t i v i t y Meter (Kerotherm BTM-D3) y a n g menggu-
n a k a n m e t o d e P r o b e , y a i t u m e n g g u n a k a n p r i n s i p d a s a r
t e k n i k p e n g u k u r a n p e n g e m b a n g a n d a r i m e t o d e k a w a t pema-
n a s ( h e a t e r ) y a n g d i s i s i p k a n l u r u s d i d a l a m p u s a t b a h ~ n
y a n g d i u k u r
,
dima.na b a h a n t e r s e b u t b e r b e n t u k s i l i n d e ra t a u b a l o k s i m e t r i s . N i l a i d i f u s i v i t a s p m a s d i c a r i
d e n g a n m e n g g u n a k a n r u m u s u n t u k m e n c a r i d i f u s i v i t a s
p a n a s , s e t e l a h d i k e t s h u i t e r l e b i h d a h u l u n i l a i - n i l a i
p a n a s j e n i s , k o n d u k t i v i t a s p a n a s d a n a a s s a j e n i s n y a .
H a s i l p e n e l i t i a n p a n a s j e n i s A p e l Malang n e n u n j u k -
k a n b a h w s m a k i n t i n g g i k a d a r a i r , n i l a i p a n a s j e n i s
m a k i n t i n g g i p u l a . H u b u n g a n a n t a . r a k a d a r a i r A p e i
Me181?8 d e n g a n p s n a s . j e n i s n y a n l e r u p a k a n hut:;lr;da.n y a n g
l i n e a r ( u n t u k k a d a r a i r a.nta.ra 8 0 . 2 2 Z - 8 5 . 4 9 % w b ) ,
y a n g d i t u n j u k k a n d e n g a n p e r s a m a a n r e g r e s i l i n e a r b e r i -
herv8.r i a s i a n t a r s 2 7 9 : : l - 4 . 3 8 8 2 J / g " C ( r a t a - r a t a 3 . 6 3 1 9 J / g " C ) .
K o n d u k t i v i t a s p a n a s Ape1 X e l a n g u n t u k s e l a n g k a d a r
s i r y a n g sama b e r v a r i s s i a n t a r a 0 . 3 8 5 0 - 0 . 6 2 8 4 W/m " C
( r a t a - r a t a 0 . 5 3 6 2 W/m "C). Hubungan a n t a r a k a d a r a i r
Apel M a l a n g der1ga.n k o n d u k t i v i t a s p a n a s n y a merupakan
hubungan y a n g L i n e a r d e n g a n p e r s a m a a n s e b a g a i b e r i k u t :
K
=
- 3 . 0 1 8 1 + 0 . 0 4 2 9 m , r = 0 . 8 3 0 8 .Untuk s e l a . n g k a d a r a i r y a n g s a m a p u l a d i d a p a t
m a s s a j e n i s Ape2 Malang b e r v a r i a s i a n t a r a 0 . 7 0 0
-
0 . 7 4 6g/cm3 ( r a t a - r a t a 0 . 7 4 2 g i c m 3 ) . Hubungan a n t a r a konduk-
t i v i t a s p a n a s d e n g a n massa j e n i s A p e l X a l a n g d i d a p a t
p e r s s m a a n :
K
= -
0 . 7 1 1 9 + 1 . 6 8 2 3 (f .
)N i l a i d i f u s i v i t a s p a n a s Apel H a l a n g u n t u k s e l a n g
k a d a r a i r sama d i d a p a t b e r v a r i a s i a n t a r a 1 . 4 8 9 6 ~ - ~
-
P E N G U K U R A N P A N A S J E N I S , K O N D U K T I V I T A S P A N A S R U A H A P E L M A L A N G ( M a l u s s i l v e s t r i s M i l l . ) D A L A M R A N G K A P E N E N T U A N N I L A I D I F U S I V I T A S P A N A S
Teddy K u s w a r d a n a
F 24.0892
S K R I P S I
S e b a g a i s a l a h s a t u s y a r a t u n t u k m e m p e r o l e h g e l a r
SARJANA TEKNOLOGI P E R T A N I A N
p a d a JURUSAN H E K A N I S A S I P E R T A N I A N
F a k u l t a s T e k n o l o g i P e r t a n i a n
I n s t i t u t P e r t a n i a n B o g o r
1992
FAKULTAS TEKNOLOGI PERTANIAN
I N S T I T U T PERTANIAN BOGOR
PENGUKURAN PANAS J E N I S , KONDUKTXVITAS PANAS BUAH APEL MALANG ( M a l u s a i l v e a t r i s M i l l . ) DALAM RANGKA PENENTUAN N I L A I D I F U S I V I T t 3 S PANAS
SKRIPSI
~ c I ~ h & a l s o o i l s a t u s y a r a t u n ~ u k memperoleh g e l a r
SARJANA TEKKOLOGI FERTANIAM
p a d a JURUSAN KEKANISASI PERTANIBN
F a k u l t a s T e k n o l o g i P e r t a n i a n
I n s t i t u t P e r t a n i a n Bogor
O l e h
T e d d y K u s n a r d a n a
F 24.0892
L a h i r : t a n g g a l 3 A p r i l 1 9 6 8
T a n g g a l l u l u s : 11 P e b r u a r i 1 9 9 2
D i s e t u j u i ,
B o g o r ,
/a
M a r e t 1 9 9 2r .
$/
K a n a r u d d i n A b d u l l a h , USA)RIWAYAT
HIDUP
P e n u l i s d i l a h i r k a n p a d a t a n g g a l 3 A p r i l 1 9 6 8 d i
C i a m i s (Jawa B a r a t ) , m e r u p a k a n a n a k b u n g s u d a r i empat
b e r s a u d a r a , k e l u a r g a E n d a j S u k e n d a r ( a y a h ) d a n T u t i
S u r y a n a r l i a t i ( i b u ) .
F e n u l i s m e m u l a i j e n j a n g p e n d i d i k a n d i S e k o l a h
Dasar N e g e r i I m b a n a g a r a 1 C i a m i s p a d a t a h u n 1 9 7 5 d a n
l u l u s p a d a t a h u n 1 9 8 1 . P a d a t a h u n 1 9 8 1 p e n u l i s m a s u k
S e k o l a h Menengah P e r t a m a Negeri 1 C i a m i s d a n l u l u s p a d a
t a h u n 1 9 8 4 . S e l a n j u t n y a p a d a t a h u n 1 9 8 4 h i n g g a t a h u n
1 9 8 7 p e n u l i s m e l a n j u t k a n d i S e k o l a h M e n e n g a h Atas
N e g e r i 1 C i a m i s .
P a d a t a h u n 1 9 8 7 p e n u l i s d i t e r i m a d i I n s t i t u t
P e r t a n i a n B o g o r ( I P B ) m e l a l u i j a l u r P e n e l u s u r a n M i n a t
Dan Kemampuan (PMDK) d a n p a d a t a h u n 1 9 8 8 p e n u l i s m e m i -
l i h F a k u l t a s T e k n o l o g i P e r t a n i a n ( F a t e t a ) d a n d i t e r i m a
d i J u r u s a n M e k a n i s a s i P e r t a n i a n .
S e b a g a i s a l a h s a t u s y a r a t u n t u k m e m p e r o l e h g e l a r
S a r j a n a T e k n o l o g i P e r t a n i a n d i I n s t i t u t P e r t a n i a n
B o g o r , p e n u l i s menyusun m a s a l a h k h u s u s d e n g a n j u d u l :
" P e n g u k u r a n P a n a s J e n i s , K o n d u k t i v i t a s P a n a s B u a h Ape1
M a l a n g ( K a l u s s i l v e s t r i s M i l l . ) Dalam R a n g k a P e n e n t u a n
N i l a i D i f u s i v i t a s P a n a s P a n a s " d i b a w a h b i m b i n g a n
K A T A P E N G A N T A R
S e g a l a p u j i b a g i A l l o h s w t . y a n g t e l a h n e n b e r i k a n
T a u f i k d a n H i d a y a h Nya, s e h i n g g a p e n u l i s d a p a t m e n y e l e -
s a i k a n s k r i p s i i n i . S o l a w a t d a n s a l a n t a k l u p a p e n u l i s
h a t u r k a n j u g a k e p a d a j u n j u n g a n N a b i B e s a r Muhammad saw.
P a d a k e s e m p a t a n i n i , p e n u l i s m e n y a m p a i k a n rasa
t e r i m a k a s i h y a n g s e b e s a r - b e s a r n y a k e p a d a :
1. B a p a k D r . H . K a m a r u d d i n A b d u l l a h , MSA s e l a k u d o s e n
p e m b i m b i n g , y a n g d e n g a n k e s a b a r a n t e l a h n e n b e r i k a n
b i m b i n g a n d a n s a r a n - s a r a n d a l a m p e n u l i s a n s k r i p s i
i n i .
2 . B a p a k I r . Mad Yamin d a n I b u I r . P u t i a t i MApp S c . ,
y a n g t e l a h b e r s e d i a m e n j a d i d o s e n p e n g u j i p a d a
S i d a n g S k r i p s i p e n u l i s .
3. ADAET/JICA, y a n g t e l a h membantu d a n a p e n e l i t i a n
m a s a l a h k h u s u s i n i .
4 . Emang d a n B i b i k e l u a r g a D r s . H . A d i n g S u r y a n a , y a n g
t a l a h membantu b i a y s p e n y u s u n a n s k r i p s i i n i .
5 . M i m i h , mamah, p a p a p , k a k a k - k a k a k d a n s e l u r u h k e l u a r -
g a , y a n g t e l a h membantu m o r i l d a n m a t e r i l s e h i n g g a
memungkinkan k e l a n c a r a n d a l a m p e n y e l e s a i a n s k r i p s i
i n i .
6 . A r i f i n , Dadan d a n r e k a n - r e k a n s a t u L a b o r a t o r i u m
E n e r g i Dan E l e k t r i f i k a s i P e r t a n i a n , y a n g t e l a h
membantu d a l a m p e n e l i t i a n .
7 . J a j a n g S u h e r l a n . r e k s n - r e k a n d i R r a v r 52 d a n s e m u a
p i h a k y a n g t e l a h rnembantu p e n u l i s d a l a m p e n e l i t i a n
d a n p e n y u s u n a n s k r i p s i i n i .
K e k u r a n g a n - k e k u r a n g a n y a n g a d a p a d 8 s k r i p s i i n i ,
k a r e n a k e t e r b a t a s a n i l m u d a n p e n g e t a h u a n y a n g a d a p a d a
p e n u l i s . O l e h k a r e n a i t u s e g a l a m a s u k a n - m a s u k a n d a l a m
p e r b a i k a n s k r i p s i i n i a k a n p e n u l i s t e r i m a d e n g a n s e n a n g
h a t i . A k h i r n y a , mudah-mudahan s k r i p s i i n i b e r g u n a b a g i
s i a p a s a . j a y a n g m e m b u t u h k a n n y a .
B o g o r , Maret 1992
DAFTAR IS1
H a l a m a n
KATA PENGANTAR
. . .
iDAFTAR I S 1
. . .
i i iDAFTAR TABEL
. . .
vDAFTAR GAMBAR
. . .
v iDAFTAR LAMPIRAN
. . .
v i iDAFTAR NOTASI
. . .
v i i i. . .
I
.
PENDAHULUAN 1. . .
.
A LATAR BELAKANG 1
B
.
TUJUAN PENELITIAN. . .
2I1
.
TINJAUAN PUSTAKA. . .
3. . .
.
A PINDAH PANAS 3
.
. . .
B PANAS J E N I S 6
C
.
D I F U S I V I T A S PANAS. . .
9D
.
PENELITIAN SEBELUMNYA MENGENAI S I F A T. . .
Til'ERffdL BAHAN 9
1
.
PENENTUAN PANAS J E N I S. . .
92
.
PENENTUAN KONDUKTIVITAS PANAS. . .
143 . PENENTUAN D I F U S I V I T A S PANAS
. . .
1 6 I11 . PERCOBAAN. . .
18A
.
BAHAN DAN ALAT. . .
18. . .
B
.
WAKTU DAN TEMPAT PENELITIAN 2 4C
.
DESAIN ALAT PENGUKUR PANAS J E N I S. . .
2 4D
.
METODE PENGUKURAN. . .
2 5. . .
E . P R O S E D U R P E N E L I T I A N
1
.
P E N E N T U A N M A S S A J E N I S. . .
2
.
P E N E N T U A N P A N A S J E N I S. . .
3
.
P E N E N T U A N K O N D U K T I V I T A S P A N A S. . .
4
.
P E N E N T U A N D I F U S I V I T A S P A N A S. . .
5
.
P E N E N T U A N KADAR A I R. . .
F
.
PENGOLAHAN D A T A. . .
I V
.
H A S I L DAN P E M B A H A S A N. . .
. . .
.
A P A N A S J E N I S
B
.
K O N D U K T I V I T A S P A N A S. . .
C
.
MASSA J E N I S. . .
D
.
D I F U S I V I T A S P A N A S. . .
V
.
K E S I M P U L A N DAN S A R A N. . .
A
.
K E S I N P U L A N. . .
B
.
SARAN. . .
DAFTAR PUSTAKA
. . .
DAFTAR TABEL
No. T e k s H a l a m a n
1. P a n a s J e n i s B u a h Ape1 Nalang 3 7
2 . P a n a s J e n i s B e r a s Super Slyp 4 0
3 . P a n a s J e n i s Ape2 Malang d a n B e r a s Super Slyp
T a n p a M e m p e r h i t u n g k a n N i l a i K o r e k s i 4 2
4 . K o n d u k t i v i t a s P a n a s Ape2 Halang 4 3
DAFTAR
GAMBARTe k s H a l a m a n
No.
1. Elemen Volume U n t u k M e n e n t u k a n P e r s a n a a n
K o n d u k s i P a n a s 4
K a l o r i m e t e r C h o u d a r y (1988) 10
K a l o r i m e t e r P a r k e r d a n S t o u t ( 1 9 6 7 ) 1 2
K a l o r i m e t e r OSHITA ( 1 9 9 1 ) 13
Alat P e n g u k u r K o n d u k t i v i t a s Pa.nas M o r i t a d a n
S i n g h 14
A l a t P e n g u k u r K o n d u k t i v i t a s P a n a s T y p e Probe 16 A l a t P e n g u k u r P a n a s J e n i s H a s i l R a n c a n g a n 19
T i m b a n g a n Type EK1200A d a n Digital Hoisture
Meter 1 9
L e m a r i P e n d i n g i n EBARA 2 0
Thermal Conductivity Meter ( Kemtherm BTH-D3)
d a n Data Logger 2 1
Oven T y p z SS-lO5D 2 2
T i n b a n g a n Exact 2 3
Hubungan A n t a r a K a d a r A i r D e n g a n P a n a s J e n i s
Ape1 Halang 3 8
Hubungan A n t a r a K a d s r A i r D e n g a n P a n a s J e c i s
B e r a s Super Slyp 4 1
Hubungan A n t a r a K a d a r A i r D e n g a n K o n d u k t i v i -
t a s P a n a s Ape1 Naleng 4 4
H u t u n g a n A n t a r a H a s s a J e n i s D e n g a n K o n d u k c i -
v i t a s P a n a s .4pel Nslang 4 8
DAFTAR
LAUPIRAN
No.
1.
2 .
3 .
4 .
5 .
T e k s Ha 1 aman
Gambar D e t a i l A l a t P e n g u k u r P a n a s J e n i s 5 5
U k u r a n D i m e n s i Minimum C o n t o h Ape1 N a l a n g 5 7
Data H a s i l P e n g u k u r a n Massa J e n i s 5 8
Data P e r k e z b a n g a n S u h u A i r C o n t o h Ape1 X a l a n g 5 9
G r a f i k P e r k e m b a n g a n S u h u A i r C o n t o h Ape1 Xa
-
l s n g 6 0
D a t a P e r k e e b a n g a n S u h u A i r C o n t o h B e r a s 6 5
G r a f i k P e r k e m b a n g a n S u h u A i r C o n t o h B e r a s 6 6
P e r h i t u n g a r . W a t e r E q u i v a l e n t R a l o r i m e t e r 7 1
DAFTAR NOTASI
q x
=
l a j u a l i r a n p a n a s y a n g m e n g a l i r a r a h s u m b u X (Watt)K
=
k o n d u k t i v i t a s p a n a s ( W a t t / c m 0 C )2
A
=
l u a s p e n a m p a n g a l i r a n p a n a s ( c m )dT/dX
=
g r a d i e n p a d a a r a h s u m b u X ( " C / c m )Cp
=
p a n a s j e n i s ( J / g e C )3
/3
=
massa j e n i s (g/c5 )t
=
w a k t u ( d e t i k )a
=
d i f u s i v i t a s p a n a s ( c m 2 / d e t i k )m
=
massa ( g )C s
=
p a n a s j e n i s sampel ( J / g ° C )C 1
=
p a n a s j e n i s a i r ( J / g ° C )W 1
=
b e r a t a i r ( g )T e
=
s u h u k e s e t i m b a n g a n ( " C )T o
=
s u h u a w a l a i r ( " C )He = h e a t c a p a c i t y k a l o r ~ n e t e r
(J/"C)
W s
=
b e r a t s a m p e l ( g )T a
=
s u h u b a h a n d a l a m r u a n g a n ( " C )Wh
=
b e r a t a i r p a n a s ( g )We
=
b e r a t a i r d i n g i n ( g )I
=
a r u s l i s t r i k ( A )R
=
t a h a n a n k a w a t (Dhm/cm)t 1 . 2
=
w a k t u p e n g u k u r a n p e r t a m a d a n k e d u a ( d e t i k )T 1 . 2
=
s u h u p e n g u k u r a n p e r t a m a d a n k e d u a ( " C )T r
=
s u h u k o r e k s i k a l o r i meter ( " C )'T:< 7. F;I.I !,I> 7, 1; 1~1 i r L,F: r i ,-1c1 6: k e s e i i r ~ k ~ a r8ga.11 ( o<: ;.
QT
=
k e n z i i k ~ n s u h u ( " C )X = i n t e r v a l wakt12 ( - )
Q T f
=
s u h u r a t a - r a t a d u a i n t e r v a l p a d a p e i o d e a k h i r("C)
A T i = s u t i u r a t a - r a t a d u a i n t e r v a l p a d a p e r i o d e a w a l ( " C )
T f = s u h u r a t s - r a t a . p a d a p e r i o d e a k h i r ( " C )
T i : s u h u r a t a - r a t a p a d a p e r i o d e a w a l ( " C )
X-1
,ZT = j u r i ~ l x h s u h u p a d a b e b e r a p a i n t e r v a l p a d a p e r i o d e
k e s e i m b a n g a n ( - )
LATAR BELAKANG
Tanaman h o r t i k u l t u r a s a a t i n i s e d a n g d i g a l a k k a n
o l e h p e m e r i n t a - h I n d o n e s i a . S a l a h s a t u a s p e k y a n g d a p a t
m e n i n g k a t k a n p e r a n a n t a n a m a n h u r t i k u l t u r a a d a l a h d e n g a n
m e n i n g k a t k a n p r o d u k s i b u a h - b u a h a n . P e n i n g k a t a n p r o d u k -
s i b u a h - b u a h a n t e r s e b u t a-kan l e b i h b a i k l a g i a p a b i l a
d i i k u t i d e n g a n p e n i n g k a t a n p e n a n g a n a n p a s c a p a n e n .
P a d a umumnya b u a h - b u a h a n s i f a t n y a mudah r u s a k .
O l e h k a r e n a . i t u p e n y impa.nari d a n p e n d i n g i n a n m e r u p a k a n
k e g i a t a n yarig s a n g a t p e r i t i n g d a l a m p e n a n g a n a n p a s c a
p a n e n , k h u s u s n y a u n t u k m e n g a u e t k s n p r o d u k s i b u a h - b u a h a n
y a n g mudah r u s a k t e r s e b u t . D e n g a n p e n y i m p a n a n p a d a
s u h u o p t i m u m d a n dengar1 p e n d i n g i n a n , b u a h - b u s h a . n a k a n
m e n g a l a m i p e n u r u n a n a k t i f i t a s e n z i m , s e h i n g g a k e r u s a k a n
j a r i n g a n d a p a t d i t u n d a , y a n g n k i b a t - n y a umur segar b u a h -
b u a h a n d a p a t d i p e r p a n j a n g . S e l a i n i t u d e n g a n p e n d i -
n g i n a . n , k e s e g a r a n a r o m a , t e k s t u r da.n n i l a i g i z i d a r i
komodit:i mas it^ d a p a t d i p e r t a t i a n k a n ( J o r d a n , R . C . dari
G . B . P r i e s t e r , 1 9 6 5 ) .
P e n y i u i p a n a n d a n p ~ r i d i n g i n a n s e l a l u b e r k a i t a n d e -
n g a n m s s a l a h g i n d u t ~ p a r l a s . O l e h k a . r e n a h a 1 t e r s e b u t ,
xiaka u n t u k i r i e n g e t a h u i u ~ a s a l a h - r n a s a l a h p i n d a h p a n a s ,
>'hT!i)' , < . ~ : : , I $ ? . , . + 5 ! ! ,: ; F
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. - a t 1her'!!1.?1 lsai;?!it . e r s r t u t f l i p * - r l i ! k a ; - ! r ! t I . -: e n a l i s i s m a s a 1 a . h p j i ? d a ! ~ p a n 3 3
s e l a m a p r o s e s pen?': :?bar.. Q i a n t ~ r a s i f a t t h e r m a l Yar!g
p e n t i n g t e r s e b u t 5 d a l a h p a n a s j e n i s , k o n d u k t i v i t a s
p a n a s d a n d i f u s i v i t s s p e r ~ a s .
D e n g a n d i k e t a k : . > i n y a n i l a i p a n a s j e n i s d a n k o n d u k -
t i v i t a s p a n a s , make n i l a i d i f u s i v i t a s p a n a s a k a n d i d a -
p a t k a n . N i l a i d i f u s i v i t a s p a n a s i n i d a p a t d i g u r ~ a k a n
u n t u k m e m p e r k i r a k t n l a j u p e n u r u n a n t e m p e r a t u r y a n g
t e r j a d i d a l a m b a h ~ n s e l a m a . p r o s e s p e n d i n g i n a n ( S e t i a -
w a n , 1 9 8 0 ) . N i l ~ i d i f u s i v i t a s p a n a s i n i p u n d a p a t
d i g u n a k a n u n t u k r e n d u g s w a k t u y a n g d i p e r l u k a n u n t u k
s u a t u p r o s e s p e r 1 s ; : l n n F s n a s .
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PENELITIANP e n e l i t i a n i r : l S e r : - j u a n u n t u k :
1 . M e r n n c a n g d a n i e n ~ t , - r a t a l a t p e n g u k u r p a n a s j e i i i s
b a h a n f, k a 1 o r i n e : s r
>
. .
2 . M e n e n t u k a n n i l . . : p a r z s j e n i s ( C @ ) b u a h A p e 1 M.?Zai?g'
d e n g a n a l a t ynr:; s u d t h d i b u a t t e r s e b u t .
3 . M e n e n t u k m n i 1 . s : : : i i r ; : ~ k . t i v i t a s p a n a s
(K)
d a n d i f i ~ ! s i -v i t n s p a i l a s i o " :-!- . . .. .Ape 1 M a l ~ ! ? d .
4 . M e m b a n J i n g k n n !-:: 1 - i - - i ? a i p a n z s J e n i s ( C p ) , kot-~c!u!.:-
..
t ; i v i t a s p a n s s K \ ; s n d i f u s i v i t a s p a n a s ( a ) b u ~ h
A s e l M n l a n q . ,.r:< .::!spat d a r i p e n e l i t i a n d j . i i t a s .
. . .
A . PJNDAH PANAS
P i n d a h p e r ~ a s d a p a t d i d e f i r i i s i k a r t s e b a g a i p e r p i n -
d a h a n s u a t u h e n t u k e n e r g i d a r i s u a t u t e m p a t k e t e m p a t
l a i n n y a , y a n g r i i s e h a h k a n a d s r i y s p e r b e d a a r i s u h u a n t a r a
d u a t e m p a t t e r s e b u t ( H e l d m a r t d a n S i n g h , 1981). S e c a r a
g a r i s b e s a r p i r . 3 a h p a n a s ants-ra b e n d a d e n g a n l i n g k u n g a n
s e k i t a r n y a d a p ~ t t e r j a d i d e n g a n 3 c a r a y a i t u : k o n d u k - s i , k o n v e k s i 3 a n r a d i a s i . Dalam t e b e r a p a k e a d a a n
k e t i g a . h e n t u k p i n d a h p a n a s t e r s e b u t a k a r t t e r j a d i s e c a r a
s e r e m p a k . T e t z g i j i k a t i d a k a d a p e r g e r a k a n y a n g c u k u p
b e s ~ r d a r i f l ; i d a s e k e l i l i n g dart f l u i d a t i d a k t e m t u s
c a h a y a . maka p i n d a h p a n a s y a n g t e r j a d i , t e r u t a m a a d a l a h
k o n d u k s i . P a d s k e a d a a n i n i p e r p i r i d a h a n p a n a s d a r i s a t u
i r t a g i a n b a n d a :.-sng t e n t b u s c a h a y a k e t e m p a t l a i n t i a n y a
, j i p e n @ a r ! ] h i c:.:?!? g r a d i e n s u h u . S e t t i n g g a d a l a i n ?e!igu--
k u r a n k o n d u k ~ i . ; i r a s p a n a s , s a r t g a t p e n t i n g u n t u k d i h i r - & -
d a r k a n bariy~i.:::;a ~ e r g e r a k a r i p a . r t i k e l d i d a l a m s i s t e r !
i M o h s e n i n . 19E: '.
H u b u n g a n i s j l ! p e r p i n d a h a r i p a n a s d e r t g a n ~ i e d i u u i k o i i -
d u k s i clan g r ~ z l e r i s u h u , d a p a t d i r t y a t a k a n m e n g g u n a k a n
4
T a n r l s r i e g a t . i : ' p i r r 1 i a t a s m e n y a t a k a n
t a w a l i r a n p a n a s y 3 . n ~ t v - : ? , ? i u ! e r ~ u J u k e t i t i k y a r i g
m e m p ~ ~ n y a i I 1 6 - h i h ren.5:;
F a d a s i s t e m k o o r d i n a t t i g a d i n ~ e n s i , t e r j a d i p i n -
d a h p a n a s p a d a . k o x ~ p o n e n - k o n p o n e n a r a h ( X ,
Y,Z)
s e p e r t ip a d a G a m b a r 1 ( B i r d , R . B . . 1 9 7 6 ) .
E e r d s s a r k a n rilnius L.c:.duksi p a n a s F o u r i e r . m a k a
p a n a s y a n g m e n g a l i r d a r i s c r o l a h k i r i d a l a m a r a h suulbu
:< ( d q s ) a d a l a h s e h s g a i t e r l s x t ( B i r d R . B . , 1 9 7 6 ) :
A l i r a n p a n a s y a n g t + ! u a r d a r i s e t e l a h , k a n a n
d , a i ! a l a t ~ rret:iagai b e r : X u t ?
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D e n g a n d e m i k i a n t o t a l a l i r a n p a n a s s e i i r a k o n z ~ k s i
d a l a u i a r a h sumbu x a d a l a h :
D e n g a n c a r a y a n g s a ~ r i a m a k a t o t a l p a r ; s s dalam a r a h
s u m b u Y d a n Z b e r t u r u t - t u r u t a d a l a h :
J u u ~ l a h a l i r a n p a n a s d a l a m a r a h k c 3 r d i n a t i i g a
d i m e n s i d i p e r o l e h d e n g a n j a l a n menjumlah.;:sn p e r s a n a a n
( 4 ) , ( 5 ) d a n ( 6 ) t e r s e b u t , s e h i n g g a d i p e r c l e r : :
J i k a . p e r s a t u a n w a k t u da.n v o l u m e d i t a r : a n k a n e r : ? r g i
p a n a s q , m a k a e n e r g i p a n a s y a n g d i b e r i k a r p s d a e l ? n e n
voluirie t e r s e b u t a d a l a h :
A l i r a n p a n a . s d a l a m e l e m e n v o l u z ~ e Y E - ; d i s e b s o k a n
o l e h k o n d u k s i da.n e n e r g i p a n a s yarig d i r - . r : k a n , a k a n
m e n a i k k a n e n e r g i d a l a m y a n g d i n y a t a k a n d e r z s z p e r s s a a a n
P a d s e l e m e n dV t e r s e b u t t e r j a d i k e s e i m b a n g a n e n e r g i
y a n g b e r p r i n s i p p a d a Hukum T h e r m o d i n a m i k s I , y a i t u
p e r u b a h a n e n e r g i d a l a m , sama d e n g a n j u m l a h a l i r a n p a n a s
k a r e n a k o n d u k s i d a n p a n a s y a n g d i b e r i k a n p a d a e l e m e n
t e r s e b u t y a n g d i n y a t a k a n d e n g a n p e r s a m a a n :
P e r s a m a a n ( 1 0 ) t e r s e b u t d a p a t d i t u l i s d a l a n b e n t u k l a i n
d i m a n a :
B . PANAS JENIS
F a n y a k n y a p a n a s y a n g d i p e r l u k a n u n t u k m e n i m b u l k a n
k e n a i k a n s u h u y a n g sama, b e r b e d a - b e d a d a r i b a h a n k e
b a h a n . P e r b a n d i n g a n a n t a r a b a n y a k n y a p a n a s :-,ang d i G e -
r i k a n 9 , d e n g a - n k e n a i k a n s u h u AT d i s e b u t K a p a s i t a s
p - -
-
d i i t i s b e n d a t e r s e b u t ( S e a r s , 1 8 5 0 ) , a t a u d e n g a n r u m u s :
K a p a s i t a s P a n a s
=
( 1 3 )7
7 j;.,
,: d a l a u i persatiia:,ri 1 1.3) t e r s ~ r . ..I i
C1
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. .. x < . , ~ . .. . i.. . ..~.
a k a r ! t:gni~:,;rii ti3.t1ua n i l r i e r i k k a p a s i t s s : it!> s ~ r i ~ a
d e n g a r , .iurrilsh p a n a s y a n g t i a r u s d i k ~ f j r i k ~ i l &..::? !ie!ida i t u
a g a r s u h u n y a n a i k s a t u d e r a j a t .
U r i t u k m e m p e r o l e h a n g k a - a r i g k a y a n g k h a s b a g i b a h a n
b e n d a i t u , maka k a p a s i t a s p a n a s p e r s a t u a n massa b a h a n
b e n d a d i d e f i n i s i k a n s e b a g a i Kapasi t a s P a n a s S e n i s
( S p e c i f i k H e a t C a p a c i t y ) b e n d a t e r s e b u t , y a n g d i b e r i
s i m b u l C p .
K a p a s i t a s P a n a s
-
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a
CF
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P a n a s j e n i s s u a t u b a h a n d i d e f i n i s i k h n s e t a g a i
p e r b a n d i n g a n a r i t a r a k a p a s i t a s p a n a s j e n i s b a h a r i i t u
d e n g a n k a p a s i t a s p a n a s j e n i s a i r . R a r e n a b e s a r n y a
h a p a s i t a s p a n a s j e n i s a i r a d a l a h 1 ka1;'gr "C a t c i u 1
B t u / l b
" F ,
maka h a r g a n u m e r i k p a r i a s j e n i s c u a t u b a h a nsarila ~ d e n g a r i k a p a s i t a s p a r i a s j e n i s r ; : v a . .... ':.ari t . * % a ~ , i
k a r e n a d i d e f i n i s i k a n s e h a g a i p e r b a n d i n g a n , n a k a h a n y a -
l a h b e r u p a b i l a n g a n t a n p a s a t u a n , s e h i r i g g a ha r g a r!snie--
r i k n y a s a m a d a l a m s e r i u a s i s t e m s a t s a n . S e r d a s a r k u n
d e f i n i s i t . e r s e b i ~ t . niaka k a p a s i t a s i:;ji;;.; . 3 , k , i _ : ~ i i . ~ .
. ~.
.,saxla d e r i g a r i h a s i l k a l i t i i a s s a b e n d a it: ~der:~:,i. ! i & p a s l ? . ~ . j -
p a n a s j r i ~ i s r ~ y a ( S e a r s . 1 9 5 0 ) .
E.er-,jassr!<ari p e r s a n l a a n i 1 4 ) . k t t p : - ~ i i . l : . . >:!I%: . - t ? : ! i : z
t . ~ r n y s t a , l5 e r a . h s e l a n g s u h u p a d a s k a ! a eui!;.! it.u mempe-
n g r r u h i b a n y a k n y a p a n a s y a n g d i p e r l u k a n u n t u k m e n a i k k a n
s u h u s e s u a t u b a h a n s e b e s a r s e l a n g s u h u y a n g k e c i l i t u .
K a p a s i t a s p a n a s j e n i s s e s u n g g u h n y a d a r i s u a t u b a h a n
p a d a s e m b a r a n g s u h u b e r d a s a r k a n p e r s a m a a n ( 1 4 ) d e n g a n
n ~ e ~ a n d a n g k e n a i k a n s u h u k e c i l t i d a k t e r h i n g g a s e b e s a . r
d t d a n j u n l a h p a n a s y a n g d i p e r l u k a n u n t u k m e n i m b u l k a n
k e n a i k a n t e r s e b u t sama d e n g a n d Q , s e h i n g g a :
1 d q p a n a s j e n i s s e s u n g g u h n y a C p
= -
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m d t
A g z r d e p a t n e n g h i t u n g i n t e g r a l n y a , Cp h a r u s d i n y a t a k a n
s t s a g a i f u r . g s i d a r i s u h u .
Ada d ~ a j e n i s p a n a s j e n i s d ~ r i s u a f u b a h a n , y a i t u
p a z a s j e r i s p a d a . t e k a n a n t e t a p d a l i p a n a s j e n i s p a d a
v o l u m e t e r s p . K a r e n a p a d a umumnya p e r l ~ b b h a n t e k a n a n
y,ar.e .. r d i d a l b m p i n d a h p a n a s h z s i ! p e r t a n i a n
ndsi.:$h k + i l , maka. y a n g b i a s a d i g u n a k a n d a l a m p e r h i -
t u n g a n p i z d s h p a n a s a d a l a h p a n a s j e n i s p a d a t e k a n a n
t e r a p . I J n - " k b e n d a p a d a t d a n c a i r a n . p e n g a r u h t e k a n a n
p a i a ~ ~ e r u > a h a r t p a n a s j e n i s n y a s a n g a t k e c i l d a n d a p a t
C . DLFUSIVITAS PANAS
D i f u s i v i t a s p a n a s d i d e f i n i s i k a n s e b a g a i l a j u
p e r a m b a t a n p a n a s s e c a r a d i f u s i d a l a m s u a t u b a h a n
( M o h s e n i n , 1 9 8 0 ) . Dalam h u b u n g a n n y a d e n g a n s i f a t p a n a s
y a n g l a i n , d i f u s i v i t a s p a n a s merupak8.n p e r b a n d i n g a n
d a r i k o n d u k t i v i t a s p a n a s
(K)
d e n g a n k a p a s i t a s p a n a s v o l u m e t r i k ( C w ) , d i m a n a k a p a s i t a s p a n a s v o l u m e t r i km e r u p a k a n h a s i l k a l i a n t a r a m a s s a j e n i s ( f ) d e n g a n
p a n a s j e n i s ( C p )
.
S e h i n g g a d i f u s i v i t a s (a) p a n a s d a p a td i r u m u s k a n s e p e r t i p e r s a m a a n (12).
D e n g a n d i k e t a h u i n y a n i l a i d i f u s i v i t a s p a n a s b a h a n ,
maka a k a n d i k e t a h u i l a j u p a n a s y a n g r l i d i f 1 3 s i k a n k e l u a r
d a r i b a h a n , s e h i n g g a a k a n d a p a t d i d u g a w a k t u y a n g
d i p e r l u k a n u n t u k s u a t u p r o s e s p e r l a k u a n p a n a s .
D . PENELITIAN SEBELUHNYA MENGENAI SIFAT
THERMAL
BAHAN1. PENENTUAN PANAS J E N I S
M e t o d e u n t u k menentuka.n n i l a i p a n a s j e n i s b a h a n
y a n g s e r i n g d i g u n a k a n a d a l a l h m e t o d r ~ a m p u r a n ( m e t h o d
o f mixtures!. M e t o d e i n i menggunakan p r i n s i p
k e s e i r n b a n g a n p a n a s , y a i t u p a n a s y a n g d i b e r i k a n b a h a n
s a m a d e n g a n p a n a s y a n g d i t e r i m a o l e h s i s t e m k a l o r i -
m e t e r . Metode i n i p a l i n g s e r i n g d i g u n a k a n m e n g i n g a t
jrki b i s a d ig:r.zkan u n t u k m e n g u k u r p a n a s . ; e n i s b u a h -
b u a h a n a.ta.up;n b i j i - b i j i a n .
l i n t u k ? t i a h - b u a h a n , F r e c h e t t e d a n Z a h r a d n i k
( 1 9 6 8 ) t e l a h m e e a k a i m e t o d e i n i u n t u k n e n g u k u r p a n a s
j e n i s b u a h A p e 1 Mc I n t o s h . D a r i p e n e l i t i a n n y a
d i d a p a t k a n b r h u a n i l a i p e n g u k u r a n p a n a s j e n i s d e n g a n
m e t a d e c a m p ; r a n , t e r n y a t a m e n d e k a t i n i l a i p a n a s
j e n i s s e s u a i d e n g a n p u s t a k a .
C h o w d a r y ( 1 9 8 8 ) j u g a t e l a h m e n g u k u r p a n a s j e n i s
m a n g g a denga:. 2 e n g g u n a k a n m e t o d e c a m p u r a n . K a l o r i -
meter y a n g 5 i g u n a k a n o l e h C h o w d a r y t e r s e b u t d a p a t
d i l i h a t pad^ .:-ambar 2 .
Vacuuni
t e m p e r a t u r e i n d i c a t o r
-
- s f : ? r : u t a m a d a r i k a l o r i m e t e r r + : s a b u t a d a l a h
s i - t .a?; : r - r m o s v a c u u m . U n t u k mengur6::gi k e h i l a n g a n
p a n e s . : i s e k e l i l i n g n y a d i t a b u r i s e z b u k g e r g a j i .
T u t ~ p t - . e r a o s t e r b u a t d a r i g a b u s k a r c c y a n g d i b e r i
d u s i u t 5ng u n t u k p e n e m p a t a n t h e r e c k o p e l , u n t u k
mer;,-ukur s u h u a i r d i d a l a m t h e r m o s t e r s e b u t .
A i r y a n g t e l a h d i k e t a h u i m a s s a n y a , d i m a s u k k a n
lie .:siar. t h e r m o s d a n s u h u n y a d i c a t a t s s m p a i m e n c a p a i
suk:u k e s e i n b a n g a n , k u r a n g l e b i h s e t e l a h 20 m e n i t .
-
h e E : d i a n c o n t o h m a n g g a y a n g a k z r d i u k u r p a n a s . .
j e n r s n y s . d e n g a n massa y a n g s u d a h d i k + t a h u i , d i c a m -
p u r r < e d a l a m t h e r m o s t e r s e b u t , d i z d u k s e b e n t a r ,
da,? s g r l n y a d i u k u r s a m p a i t e r c a p a i s u h u k e s e i m -
b a r . 2 ~ ~ . .
>n: :k u e n g h i t u n g n i l a i p a n a s j e n F s n y a d i g u n a k a n
perssrs$.-. s e b a g a i b e r i k u t :
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W s ( T a - T e )
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C 1 Wc ( T e - 7 :- - - i 1 9 )
( T e - T o !
. .
-
-
:r.g d3n Hayakawa ( 1 9 7 9 ) t e l a . L r e n g u k u r n i l a i
m e n g g u n a k a n m e t o d e i n i u n t u k m e n g u k u r p a n a s j e n i s
t a r t cherries. K a l o r i m e t e r y a n g d i g u n a k a n P a r k e r
C h e r y y a n g a k a n d i t e n t u k a n p a n a s j e n i s n y a
d i t e m p a t k a n d i b a g i a n e t a s k a l o r i m e t e r p a d a tem- d a n S t o u t t e r s e b u t d a p a t d i l i h a t p a d a Gambar 3 .
C h e r r y
P o l y s t y r e n e
-
T u t u p a t a sT u t u p d a s a r
p e r a t u r r u a n g d a n a i r d e n g a n s u h u 40
"F
d i t e m p a t k a nd i b a g i a n d a s a r k a l o r i m e t e r d i d a l a m r u a n g a n d i n g i n .
K e d u a t u t u p b a g i a n a t a s d a n d a s a r d i t u t u p . B a g i a n
-
-
-
-
-
+-
-
- - -
a t a s d i b a w a k e r u a n g a n d i n g i n d a n d i t e m p a t k a n t e r b a -
l i k d i b a g i a n b a w a h . S e t e l a h s u h u a w a l d i c a t a t , - A i r
[image:27.556.125.500.76.712.2]m a s i n g - m a s i n g t u t u p d i c a b u t , s e h i n g g a c o n t o h c h e r r y
.
Gambar 3 . K a l o r i m e t e r P a r k e r d a n Stout (1967)
masuk k e a i r d i n g i n . Kediia t u t u p d i t u t u p l a g i u n t u k
m e n g u r a n g i k e h i l a n g a n p a n a s . Suhu d i u k u r h i n g g a
K a l o r i m e t e r y a n g d i g u n a k a n t e r s e b u t t e r b u a t
d a r i p o l y s t y r e n e , d e n g a n b a g i a n d a s a r d i s e l i m u t i
p a r a f f i n y a n g t e l a h d i k e t a h u i j u a l a h n y a u n t u k meng-
h i n d a r k a n a b s o r p s i a i r k e p a d a polystyrene. P a n a s
j e n i s d i h i t u n g d e n g a n p e r s a m a a n p a n a s y a n g h i l a n g
d a r i c o n t o h d e n g a n p a n a s y a n g d i d a p a t a i r d a n p a r a f -
f i n .
U n t u k m e n g u k u r p a n a s j e n i s b i j i - b i j i a n , m e t o d e
c a m p u r a n j u g a t e l a h b a n y a k d i g u n a k a n . P f a l z n e r
( 1 9 5 1 ) t e l a h m e n g u k u r p a n a s j e n i s gandum, W r a t t e n e t
a1 ( 1 9 6 9 ) s e r t a K a z a r i a n d a n H a l l ( 1 9 6 5 ) m e n g u k u r
p a n a s j e n i s b e r a s , gandum d a n j a g u n g . S e d a n g k a n
M o r i t a d a n S i n g h ( 1 9 7 9 ) m e n g u k u r p a n a s j e n i s b e r a s .
S e l a i n i t u O s h i t a ( 1 9 9 1 ) j u g a t e l a h m e n g u k u r
p a n a s j e n i s b e r a s , y a i t u d e n g a n menggunakan k a l o -
r i m e t e r s e p e r t i Gambar 4 .
conta
water
. n e r
box
[image:28.556.110.505.233.719.2]A i r d e n g a n m a s s a y a n g s u d a h d i k e t a h u i d i m a s u k -
k a n k e d a l a m k a l o r i m e t e r , s a m b i l d i a d u k . C o n t o h
b e r a s d e n g a n s u h u k a m a r d a n s u d a h d i k e t a h u i m a s s a n y a
d i c a m p u r k a n k e d a l a m a i r t e r s e b u t s a m b i l t e r u s
d i a d u k s a m p a i t e r c a p a i s u h u k e s e i m b a n g a n . P a n a s
j e n i s b e r a s d i h i t u n g d e n g a n m e n g g u n a k a n r u m u s s e b a -
g a i b e r i k u t :
Hc ( T e
-
T o ) C s=
W s ( T a
-
T e )2.
PENENTUAN KONDUKTIVITAS PANAS
M o r i t a d a n S i n g h ( 1 9 7 9 ) t e l a h m e n e n t u k a n n i l a i
k o n d u k t i v i t a s p a n a s b e r a s d e n g a n m e t o d e l i n e heat
source. Alat
Gambar 5 .
y a n g d i g u n a k a n n y a d a p a t
c m - c s y c n a a
[image:29.556.110.509.94.727.2]d i l i h a t p a d a
15
I r t u i f : ~ ~ g u k . i ~ r k o r i d u k t i v i 1 . n : - ; p a r i n s . s i l i n d e r
t j i i i ; i t ~ e r a s d e r i g a r ~ c a r a n ~ e n g e t u k r ~ y a t f e r u s m e n e r u s
h i r i g g n p e n g i s i s i - I n 1 e r i g h a s i 1 k a . n m a s s a j e n i s y a n g
s e r a g n m . P o t e n s i o m e t e r r e c o r d d i g u n a k a n u n t u k m e n g -
u k u r s u h u a w a l d i p u s a t c o n t o h b e r a s . K e t i k a s u h u
i r i i t e l a h s t a b i l , a r u s l i s t r i k d i h i d u p k 8 . n d a n d i k o n -
t r o l v l e h ampere meter. S u h u selama p e r c o b a a n d i -
u k u r s e c a r a t e r u s m e n e r u s o l e h p o t e n s i o e e t e r d a n
d i h e n t i k a n s e t e l a h k u r a n g l e b i h 5 m e n i t .
D a t a s u h u d i p l v t k a n k e d a l a m k e r t a s semi loga-
r i t u i a , h i n g g a d i d a p a t k a n g a r i s l u r u s . N i l a i y a n g
d i h a . s i 1 k a . n d a r i g a r i s l u r u s t e r s e b u t d i g u n a k a n u n t u k
m e n g h i t u n g n i l a i k o n d u k t i v i t a s pa.na.s b e r a s t e r s e b u t ,
y a i t u s e b a g a i b e r i k u t :
C h o w d a r y ( 1 9 8 8 ) m e n c o b a m e n g u k u r k o n d u k t i v i t a s p a n a s u i a n g g a d e n g a n u i e n g g u n a k a n m e t o d e Probe, sama
s e p e r t i y a n g d i l a k u k a n o l e h S w e a t d a n H a u g h ( 1 9 7 4 ) ,
y m g d i p e r b a i k i o l e h B a g h e K h a n d a n e t a1 ( 1 9 8 1 ) .
A l a t p e n g u k u r k n n d u k t i v i t a s m e t u d e P r o b e t e r s e b u t
d a p a t d i l i h a t p a d 8 ( ; a m b a r 6 . U n t u k n ~ i j r ~ g h i t u r i g n i l a i
k o n d u k t i v i t a s p a n a s n y a d i g u n a k a n p e r s a m a a n sama
d e n g a n p e r s a t r i a a n ya.rig d i l a k u k a n o l e h N o r i t a . d a n
Silicon H e a t Conduclmp
Compound
Heater Wirso
Sewing Nesdls
Gambar 6 . A l a t P e n g u k u r R u n d u k t i v i t a s P a n a s T i p e P r o b e
3 .
PENENTUAN DIFUSIVITAS PANAS
U n t u k r r i e n g h i t u n g n i l a i d i f u s i v i t a s p a n a s b e r a s ,
M o r i t a d a n S i n g h ( 1 9 7 9 ) m e n g g u n a k a n p e r s a m a a n ( 1 2 ) ,
dirrtana n i l a i - n i l a i k o n d u k t i v i t a s p a n a s , m a s s a j e n i s
d a n p a n a s j e n i s n y a . d i d a p a t d a r i h a s i l p e n e l i t i a n .
F r e c h e t t e dart Z a h r a d n i k ( 1 9 6 8 ) t e l a h r n e n e l i t i
d i f u s i v i t a s pans-s u n t u k s a t u b u a h A p e 1 Mc I n t o s h .
D s l a m p e n e l i t i a n n y a d i g u n a k s n m e d i a p e n d i n g i n a l i r a n
a i r d i n g i n y a n g t e m p e r a t u r n y a k o n s t a n 0 . 5 6 " C ,
dengktan k e c e p a t a n 2 . 5 r i e t e r / d e t i k . M e t o d e y a n g
d i i a k u k a n u l e h F r e c h e t t e d a n Z a h r a d n i k t e r s e b u t
s u k a r u n t u k d i t e r a p k a r i d i s i n i , u ~ e n g i n g a t p e r a l a t a n
[image:31.556.160.512.59.450.2].:~t.n:j d e n g a i t niertt~rspkiiri m e t o d e yartg l e b i h s e r j e r t l a r i a ,
::ai !.ti ntt-t-~ide l 4 u n i e r i k , y a n g d i g u n a k a r i turituk nierigtii-
t u r i g /J ,-i:+ri L u a h - b u a h a n b e r b e n t u k b u l a t ( J a m h u H i j i ,
S a w o , Ape1 Malarig d a n A l p u k a t ) . Gde Haridi ( 1 9 5 2 )
m e n c o b a m e m b a n d i n g k a n a n t a r a m e t o d e N u m e r i k y a n g
( d i p a k a i S e t i a w a n ( 1 9 8 0 ) , d e n g a n m e t o d e A n a l i t i k ,
d a l a n r m s n e n t u k a n n i l a i a b u a h J e r u k S i y e m ( C . n o b i -
lis L o u r ) . D a r i h a s i l p e n e l i t i a n n y a d i d a p a t s e d i k i t
p e r b e d a a n a n t a r a n i l a i h a s i l m e t o d e N u m e r i k d e n g a n
m e t o d e A n a l i t i k .
H a r s i t o r u k m i ( 1 9 8 7 ) d a n S o n t i n g U m a r ( 1 9 8 7 ) ,
j u g 8 t e l a h m e n g g u n a k a n m e t o d e N u m e r i k d a n A n a l i t i k
d a l a m p e n e l i t i a n d i f u s i v i t a s p a n a s . H a r s i t o r u k m i
( 1 9 5 7 ) m e n e l i t i b u a h Sernangka ( C i t r u l l u s v u l g . a r i s
S c h r a d i, s e d a n g k a n S o n t i n g Umar m e n e l i t i b u a h Melon
( C u c u m i s melo L . ) .
D a . r i h a s i l - h a s i l p e n e l i t i a n n y a , Gde H a r i d i ,
Ha.rsit:orukrni dart S o n t i n g Umar t e l a h r n e n y i m p u l k a n
satiwa m e t o d e N u m e r i k l e b i h b a i k d i g u n a k a n d a r i p a d a
me t u d e A n a l i t i k , d a l a m m e n e n t u k a r i n i l a i d i f u s i v i t a s
r n r t n s b r ~ a h - b u a h a r i y a n g d i t e l i t i n y a , k a r e n a d a g a t
z i e n g t t ~ s i l k a r i p e n y i i r i p a n g a n r a t a - r a t a s u h u p e r h i t u n g a n
111. PERCOBAAN
A . BAHAN DAN ALAT
Bahan y a n g d i g u n a k a n d a l a m p e n e l i t i a n i n i a d a l a h
b u a h Ape1 M a l a n g y a n g d i b e l i d a r i S w a l a y a n Mitra, b e r a s
S u p e r S.7yp d a n e s b a t u . C o n t o h Ape1 M a l a n g d a p a t
d i l i h a t p a d a Gambar 7 .
A l a t - a l a t y a n g d i g u n a k a n d a l a m p e n e l i t i a n i n i
a d a l a h :
1. K a l o r i m e t e r b a s i l r a n c a n g a n
2 . L e m a r i p e n d i n g i n EBARA, k a p a s i t a s 1 . 0 kVA, t e g a n g a n
I P 2 2 0
V
5 0 Hz, k o m p r e s o r 3 0 0W ,
m o d e l 3 8 4 8 . 3 . Data L o g g e r , t i p e YODAC 855.4 . T h e r m a l C o n d u c t i v i t y Meter ( K e m t h e r m BTM-D3), b u a t a n
K y o t o E l e c t r o n i c s M a n u f a c t u r i n g C o . , LTD.
5 . T h e r m o l i o p e l t y p e C o p p e r - C o n s t a n t a ( C C ) , d i a m e t e r 0 . 3
mm .
6 . Oven t y p e S S - I O 5 D
7 . T i m b a n g a n E x a c t d a n t i m b a n g a n t y p e EK-IZOOA
8 . D i g i t a l m o i s t u r e m e t e r , M o d e l TD-1, b u a t a n Oga
E l e c t r i c C o . , LTD, r a n g e 1 0 %
-
3 0 % , a c c u r a c y 0 . 5;i ( 1 0
Z
-
2 0 % ) .9 . ela as u k u r , j s n g k a s o r o n g , p e n g g a r i s d a n
eral la tan
p e m b a n t u l a i n
A l a t - a l a t y a n g d i g u n a k a n t e r s e b u t d a p a t d i l i h a t
Gambar 7. C o n t o h A ~ e l
Malang Yang
D i t e l i t iGambar 8. A l s t F s n g u k u r P a n a s J e n i s H a s i l i s n -
Gambar 9 . Timbangan T y p e
EK1200A
d a n D i g i t a l M o i s t u r e M e t e rGambar 10. T h e r m a l C o n d u c t i v i t y M e t e r (Kemtherm
H.
WAKTU D A N TEUPAT PENELITIANP e n e l i t i a n i n i d i l a k s a n a k a n d a r i m u l a i t a n g g a l 2
S e p t e m b e r s a m p a i d e n g a n t a n g g a l 16 November 1 9 9 1 .
T e m p a t p e n e l i t i a n a d a l a h d i L a b o r a t o r i u m E n e r g i d a n
E l e k t r i f i k a s i P e r t a n i a n , J u r u s a n H e k a n i s a s i P e r t a n i a n
d a n d i L s b o r a t o r i u m K i m i a P a n g a n , J u r u s a n T e k n o l o g i
Pangs-n d a n G i z i , u n t u k p e n g a n b i l a n d a t a - d a t a . S e d a n g -
kart u n t u k p e m b u a t a n a l a t p e n g u k u r p a n a s j e n i s ( k a l o r i m -
e t e r ) d i l a k u k a n d i B e n g k e l H e k a n i s a s i P e r t a n i a n , y a n g
d i k e r j a k a n d a r i t a n g g a l 2 S e p t e m b e r sampai d e n g a n
t a n g g a l 24 S e p t e m b e r 1 9 9 1 . P e n g u j i a n a l a t d a n pengum-
p u l a n d a t a - d a t a d i l a k u k a n p a d a t a n g g a l 2 O k t o b e r s a m p a i
d e n g a n t a n g g a l 1 6 November 1 9 9 1 .
C . DESAIN ALAT PENGUKUR PANAS J E N I S
A l a t p e n g u k u r p a - n a s j e n i s y a n g d i d e s a i n i n i b a g i a n
u t a m a n y a a d a l a h s e b u a h t h e r m o s b e r b e n t u k s i l i n d e r
d e n g a n d i a m e t e r 6 c m , t i n g g i 1 2 c m . U n t u k m e n g u r a n g i
k e h i l a n g a n p a n a s k a r e n a k o x d u k s i , d i s e k e l i l i n g t h e r m o s
t e r s e b u t d i i s o l s s i d e n g a n s u s a k a r e t d a n k e r t a s p e r a k .
S e l a i n i t u d i b u a t j u g a k o t s k k a y u s e t e b a l 2 cm, d e n g a n
u k u r a n ( p a n j a n g X l e b a r X t i n g g i ) a d a l a h 2 2 . 5 cm X 2 2 . 5
CITI X 2 7 . 5 crr~ p a n g s e k e l i l l n g n y a d i i s o l a s i j u g a d e n g a n
s t y r o f o a m d a n k e r t a s p e r a k .
B a g i a n - b a g i a n l a i n d s r i a l a t p e n g u k u r p a n a s j e n i s
1 T h e r m o k o p e l , b e r f u n g s i u n t u k m e n g u k u r s u h u a l r d a n
s u h u b a h a n s e l a m a p e n e l l t l a n . T h e r m o k o p e l y a n g
d i g u n a k a n a d a l a h t h e r m o k o p e l t y p e Copper-Constants
(CC).
2 . P e n g a d u k , b e r f u n g s i u n t u k m e n g a d u k a i r d a n b a h a n d i
d a l a m s i l i n d e r , a g a r s u h u n y a merata, s a m p a i t e r c a p a i
s u h u k e s e i m b a n g a n . P e n g a d u k i n i d i b u a t d a r i w i n g
s k r u p , d e n g a n b a t a n g t e r b u a t d a r i b e s i .
3 . Motor, b e r f u n g s i u n t u k m e n g g e r a k k a n p e n g a d u k . M o t o r
i n i memakai m o t o r t a p e , t e g a n g a n 12 v o l t , a r u s 1
a m p e r e . S e b a g a i s u m b e r a r u s d i g u n a k a n a d a p t o r
t e g a n g a n 1 2 v o l t d a n a r u s 1 a m p e r e . Dari m o t o r k e
p e n g a d u k , d i h u b u n g k a n o l e h k a r e t p u l l e y t a p e .
Gambar d e t a i l a l a t p e n g u k u r p a n a s j e n i s t e r s e b u t
d a p a t d i l i h a t p a d a Gambar 7 d a n L a m p i r a n 1.
D . KETODE PENGUKURLW
Metode y a n g d i g u n a k a n u n t u k m e n e n t u k a n p a n a s
j e n i s ape1 d a n b e r a s d a l a m p e n e l i t i a n i n i m e n g g u n a k a n
o t e t o d e caslpurart (method o f m i x t u r e s ) , k a r e n a m e t o d e i n i
s e d e r h a n a d a n umum d i g u n a k a n u n t u k p e n g u k u r a n p a n a s
j e n i s h s s i l p e r t a r t i a n . Pa.da m e t o d e i n i d i g u n a k a n
p e r s a m a a n k e s e i m b a n g a n pa.na.s a n t a r a b a h a n d a n s i s t e m
k a l a r i m e t e r , d i o t a n a p a n a s y a n g d i b e r i k s n o l e h b a h a n
s a n a d e n g a n p a n a s y a n g d i t e r i m a o l e h s i s t e m k a l o r i m e -
2 6
c s
y j ( T a - T e ) = C 1 W 1 ( T e - T o ) + C c Wc ( T e - T o ) ( 2 2 )a t a u
~1 w 1 ( T e - T o ) + C c Wc ( T e - T o )
C s
=
( 2 3 )W s ( T a - T e )
d i m a ~ a h a r g a C c
Wc
d i a n g g a p k o n s t a n=
H c . Harga terse-b u t e i n y a t a k a n sebagai h e a t c a p a c i t y d a r i k a l o r i m e t e r ,
s e h i a g g a p e r s a m a a n ( 2 3 ) t e r s e b u t m e n j a d i s e b a g a i b e r i -
k u t :
~1 w 1 ( T e - T o ) + Hc (Te-7'0) C s
=
Ws ( T a - T e )
U n t u k m e n e n t u k a n h e a t c a p a c i t y d a r i k a l o r i m e t e r ,
d i l a k u k a n p e n g u j i a n d e n g a n m e n g g u n a k a n b a h a n y a n g t e l a h
d i k e t a h u i n i l a i p a n a s j e n i s n y a . U n t u k p e n g u j i a n i n i
d i g u x a k a n a i r m u r n i y a n g mempunyai p a n a s j e n i s p a d a
s u h ~ s e k i t a r 2 8 " C s e b e s a r 4 . 1 7 7 KJ/'Kg " C .
K a l o r i m e t e r y a n g d i g u n a k a n d a l a m p e n e l i t i a n i n i ,
t i a e c l a h s e s e m p u r n a m u n g k i n , k a r e n a k e m u n g k i n a n k e b o c o -
r a n F a n a s d a r i l i n g k u n g a n k e d a l a m k a l o r i m e t e r m a s i h
t e r : s d i . P e r b e d a a n s u h u d i d a l a m k a l o r i m e t e r d e n g a n
s u h r 1 i n g k u n g a n n y a m e m u n g k i n k a n t e r j a d i n y a p e r a m b a t a n
p a n e s d a r i l i n g k u n g a n k e d a l a m k a l o r i m e t e r , w a l a u p u n
d a l ~ n j u m l a h y a n g k e c i l . U n t u k m e n g u r a n g i k e b o c o r a n
p a n i s t e r s e b u t , maka k a l o r i m e t e r d i i s o l a s i d e n g a n b u s a
kayu y x n g d i i s o l a s i j u g a d e n g a n styrofoan d a n k e r t a s
p e r a k . Dengan a d a n y a l a p i s a n i s o l a s i t e r s e b u t m a k a
d i h a r a - p k a n k e b o c o r a n p a n a s a k a n s e k e c i l m u n g k i n .
P e n a m b a h a n p a n a s d a p a t t e r j a d i p u l a k a r e n a a d a n y a
p e n g a d u k a n d i d a l a m k a l o r i m e t e r , y a i t u p e n g a r u h g e s e k a n
a n t a r a l o g a m p e n g a d u k d e n g a n t u t u p k a l o r i n e t e r ( m i k a )
a t a u g e s e k a n a n t a r a pulley d e n g a n k a r e t pulley, selama
p e n e l i t i a n
.
P e n g a r u h - p e n g a r u h p a n a s d a r i l i n g k u n g a nd a n a l a t t e r s e b u t , a k a n n e n y e b a b k a n s u h u k e s e i m b a n g a n
p a d a w a k t u p e n c a m p u r a n l e b i h t i n g g i d a r i s u h u k e s e i m -
b a n g a n s e b e n a r n y a , y a i t u s u h u k e s e i m b a n g a n y a n g h a n y a
d i s e b a - b k a n o l e h b a h a n y a n g d i u k u r w a k t u p e n c a m p u r a n .
U n t u k m e n g h i l a n g k a n p e n a m b a h a n p a n a s p a d a s u h u
k e s e i m b a n g a n t e r s e b u t , m a k a d i g u n a k a n c a r a s e p e r t i y a n g
d i l a k u k a n o l e h P f a z n e r ( K o h s e n i n , 1980), y a i t u mengu-
r a n g i s u h u k e s e i m b a n g a n y a n g d i d a p a t k a n d e n g a n s u h u
k o r e k s i t e r h a d a p p i n d a h p a n a s ( T r ) , s e h i n g g a a k a n
d i d a p a t k a n s u h u k e s e i m b a n g a n y a n g s e b e n a r n y a . B i l a
t i d a k d i l a k u k a n p e n g u r a n g a n s u h u k o r e k s i t e r h a d a p s u h u
k e s e i m b a n g a n , maka a k a n d i d a p a t k a n n i l a i p e n g u k u r a n
p a n a s j e n i s ya.ng l e b i h b e s a r d a r i p a d a n i l a i p a n a s
j e n i s s e b e n a r n y a .
K o r e k s i t e r h a d a p p i n d a h p a n a s ( T r ) y a n g d i b e r i -
kan o l e h P f a z n e r ( M o h s e n i n , 1 9 8 0 ) t e r s e b u t , a d a l a h
AT f
-AT
i To+Tx T r=
T x -To -AT+
XnTi + -T f - T i 2
P e r s a m a a n ( T r ) d a p a t d i t e n t u k a n d a r i g r a f i k k e n a -
i k a n s u h u a i r d a l a m k a l o r i m e t e r t e r h a d a p w a k t u . D e n g a n
memasukkan h a r g a ( T r ) k e d a l a m p e r s a m a a n ( 2 4 ) , m a k a
a k a n d i d a p a t p e r s a m a a n s e b a g a i b e r i k u t :
C 1 W 1 ( T e
-
T o-
T r )+
Hc ( T e-
To-
T r )C s
=
( 2 6 )Ws ( T a
-
T e + T r )Untuk m e n g u k u r p e r k e m b a n g a n s u h u d i d a l a m k a l o r i -
m e t e r s e l a m a p e n e l i t i a n , d i g u n a k a n t h e r m o k o p e l Copper-
C o n s t a n t a ( C C ) , y a n g d i m a s u k k a n k e d a l a m k a l o r i m e t e r
m e l a l u i k a r e t y a n g d i l u b a n g i . M a s a l a h y a n g s u k a t i m b u l
p a d a w a k t u p e n g u k u r a n s u h u t e r s e b u t a d a l a h k a d a n g -
k a d a n g t h e r m o k o p e l t e r s e b u t i k u t b e r p u t a r b e r s a m a
p e n g a d u k , s e h i n g g a s u k a m e m b e l i t p e n g a d u k t e r s e b u t .
A k i b a t n y s p e n g a d u k a n m e n j a d i m a c e t a t a u b e r h e n t i .
U n t u k m e n a n g g u l a n g i m a s a l a h t e r s e b u t , maka s e b e l u m
p e n e l i t i a n d i l a k u k a n , t h e r m o k o p e l t e r s e b u t d i r e k a t
d e n g a n p l e s t e r k e k a l o r i m e t e r , s e h i n g g a k e d u d u k a n
m a n t a p , t i d a k b i s a i k u t b e r p u t a r .
Dalam p e n g a d u k a n a i r d i d a l a m k a l o r i m e t e r , d i g u n a -
k a n p e n g a d u k y a n g d i g e r a k a n o l e h m o t o r . S i s t e m p e n g a -
d u k a n t e r s a b u t d i l a - k u k a n d e n g a n m e n g g u n a k a n p ~ l l l e y .
Ka.rena m o t o r y a n g d i g u n a k a n mempunyai rpm y a n g t i n g g i ,
y a n g b e s a r n y a b e r b e d a , a n t a r a p u l l e y p a d a m o t o r d e n g a n
p u l l e y p a d a p e n g a d u k , d i m a n a p u l l e y p a d 8 m o t o r l e b i h
k e c i l d a r i p a d a p u l l e y p a d a p e n g a d u k . S e l a i n m e n g g u n a -
k a n p u l l e y y a n g b e s a r n y a b e r b e d a , u n t u k m e m p e r l a m b a t
p e r p u t a r a n p e n g a d u k , j u g a d i l a k u k a n d e n g a n m e r u b a h -
r u b a h t e g a n g a n p a d a a d a p t o r . Makin k e c i l t e g a n g a n y a n g
d i b e r i k a n , maka m a k i n l a n b a t p u t a r a n ya.ng t e r j a d i .
U n t u k m e n e n t u k a n k o n d u k t i v i t a s p a n a s A p e 1 Halang,
d a l a m p e n e l i t i a n i n i d i g u n a k a n p r i n s i p d a s a r t e k n i k
p e n g u k u r a n p e n g e m b a n g a n d a r i m e t o d e k a w a t p e m a n a s
( h e a t e r ) y a n g d i s i s i p k a n l u r u s d i d a l a m p u s a t b a h a n
y a n g d i u k u r , d i m a n a b a h a n t e r s e b u t b e r b e n t u k s i l i n d e r
a t a u b a l o k siruetris, y a n g d i s e b u t m e t o d e Probe, d i m a n a s e b a g i a n d a r i b a h a n d i g a n t i k a n o l e h s u a t u m a t e r i a l y a n g
d i k e t a h u i h a r g a k o n s t a n t a n y a . K o n d u k t i v i t a s p a n a s
d i t e n t u k a n d e n g a n m e n g g u n a k a n r u m u s s e b a g a i b e r i k u t :
S e t e l a h d i k e t a h u i n i l a i k o n d u k t i v i t a s p a n a s ( K ) ,
n i l a i n i a s s a j e n i s (
("
! d a n n i l a i p a n a s j e n i s ( C p \ , maka u n t u k rnenentuk8.n n i l a i d i f u s i v i t a s p a n a s ( a ) b u s h a p e 1d i g u n a k a n r u m u s u n t u k m e n c a - r i n i l a i d i f u s i v i t a s p a n a s
PROSEDUR PENELITIAN
1. PENENTUAN WASSA J E N I S
I J n t u k m e n c a r i u l a s s a j e n i s bu8.h a p e l , p e r t a m a
d i a n g g a p b a h w a a p e l b e r b e n t u k b o l a , y a i t u u n t u k
memudahkan m e n g u k u r v o l u m e a p e l t e r s e b u t . P r o s e d u r
u n t u k m e n c a r i massa j e n i s a p e l t e r s e b u t a d a l a h
s e b a g a i b e r i k u t :
a . Apel d i u k u r d i a m e t e r n y a d e n g a n m e n g g u n a k a n j a n g k a
s o r o n g , d i l a k u k a n m i n i m a l t i g a k a l i u l a n g a n ,
u n t u k m e n d a p a t k a n n i l a i rata-rats-nya.
b . A p e l d i t i m b a n g d e n g a n t i m b a n g 8 . n t y p e EK1200A.
c . D i c a r i v o l u m e a p e l d e n g a n m e n g g u n a k a n r u m u s u n t u k
m e n c a r i v o l u m e b o l a , y a i t u :
Volume
=
4 / 3 n r 3 ( 2 8 )d
.
D i h i t u n g massa j e n i s ((2 )ny8. d e n g a n m e n g g u n a k a nr u m u s s e b a g a i b e r i k u t :
f
=
massa ,/ v o l u r ~ e ( 2 9 )PENEHTUAN PANAS J E N I S
I J n t u k menen t u k a n p a n a s j e n i s b u a h a p e l p r o s e -
d u r y a n g d i l a k u k a n a d a l a h s e b a - g a i b e r i k u t :
a . T h e r t n o s d i i s i d e n g s n a i r d i n g i n s e t a n y a k 180 g .
b . P e n g a d u k d i j a l a n k a n u n t u k r i e n g a d u k a i r t e r s e b u t ,
d a n p e r k e m b a n g a n s u h u n y a d i u k u r d e n g a n d a t a
d i k t a ~ ~ i n:?s.;;inya - ~ i . n d a .;:~:iu k a n r a r . d i r i s . s : u k i ; a r !
k e d a l a m t<!-icrmos y a i ~ g t e r i s i a i r t e r s e b u t .
S e m e n t a r a it11 p e n g a d u k s n d a n p e n c a t a t a - n p e r k e m -
b a n g a n s u h u t e r u s d i l a k u k a n .
d . P e n e l i t i a r ~ d i t i e n t i k a n s e t e l a h k u r a n g l e t i h 600
d e t i k .
D a r i d a t a - d a t a y a n g d i d a p a t , d e n g a n m e n g g u n a k a n
p e r s a m a a n ( 2 4 ) rjkan d i d a p a t n i l a i p a n a s j e n i s a p e l
y a n g d i c a r i
.
i l n t u k m e n e l i t i 8 p a k a . h h a s i l p e n g u k u r a n p a n a s
j e n i s a p e 1 d i a t a s t e n a r a t a u t i d a k , m a k a d i c o b a .
j u g a . d i u k u r p a n a s j e n i s t e r a s Super 5 1 d e n g a n ~ ~ ~
p r o s e d u r s e p e r t i u n t u k m e n e n t u k a n p a n a s j e n i s a p e 1
d i a t a s .
3 .
PENENTUAN KONDUKTIVITAS
PANAS[ J n t u k r i e n e n t u k a n k o n d u k t i v i t a s p a n a s a p e l ,
d i p a k a i a l a t C o n d ~ ~ c t i r r i t.v Meter Cliemther~n BTPi-D3>
.
P r o s e d u r u n t ~ u k m e r t e n t u k a n k c i n d u k t i v i t a s p a n a s a p e 1
t e r s e b u t a d a l a i - I 5 e b a g a . i b e r i k u t :
a . 5z.v;.1?l y a n p ' ;.i:r~ c l i u k u r . d i p o t o r i g dalalrr t e n t u k
h a l o k rlenpni-I u k i i r s i : t e r t e i ; : . u s e s u a i d e i i g a r ~ p e r
s y a r a t a n y a n g s u d a h d i t e n t u k a r i , a t a u s e s u a i
d e n g a n u k u r s n d i m e n s i minimum y a n g d a p a t d i l i h a t -
32
dart b i l a . s a m p l e nter-ignr~f:I~ing a i r , make a n t a r a p r o b e
. .
darr s a m p l e h a r u s d i l a p ~ s l d e n e a n b a h a n i s o l a t o r .
b . P e r s i a p a r t a l a t , y a i t u p r o b e d i h u b u n g k a n p a d a
a l a t u k u r , k a b e l p a d 8 p o u e r - s u p p l y 220 V , d a n
n y a l a . k a n a l a t s e l a m a l e b i h k u r a n g 30 n e n i t u n t u k
p e m a n a s a n .
c . S e s u a i k a n h a r g a k o r r s t a n t a K1,
HZ,
K2 d a nHZ
d e n g a - n h a r g a y a n g t e r t e r a p a d a t a b e l probe con
s t a n t s c a r d .
d . L e t a k k a n probe d i a t a s s a m p l e .
e . S e s u a . i k a n h a r g a a r u s h e a t e r y a n g d i g u n a k a n
b e r d a s a r k a n k o n d u k t i v i tss s a m p l e y a n g a k a n
d i u k u r .
f . T e k a n t o m b 0 1 r e s e t , dart t u l i s s n g k a - a n g k a u n t u k
G . No, S . No d a n REPT t i m e . T e k a n t o m b o l r e s e t ,
p i l i t i mode p e n g u k u r a n , d a n t e k a n t o m b o l s t a r t .
P e n g u k u r a - n d i m u l a i , dart a k a n d i t a m p i l k a n h a s i l -
n y a s e t e l a h 15 m e n i t d a r i s t a r t .
g . S e t e l s h s e l e s a i p e n g u k u r a n , m a t i k a n p o w e r - s u p -
4 .
PENENTUAN DIFUSIVITAS PANAS
S e t e l a h n i l a i - r t i l a i k o n d u k t i v i t a s p a n a s ( K ) ,
m a s s a j e n i s ( f ' , d s n p a r t a s j e n i s ( C p ) d i d a p a t k a n
d a r i p e r t e l i t i a r r d i a t a s , maka r r i l a i d i f u s i v i t a s
3 3
i i i l a j I v a r . s r i a s ( a ) t e r s e b u t , digiuriakan
p e r s n a i n a i l i. 12 ! .
5 . PENENTUAN RADAR A I R
l l n t u k m e n g e t 6 . h u i h u b u n g a n a n t a r a k
