air independent power systems
TRANSCRIPT
7/23/2019 Air Independent Power Systems
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AIR INDEPENDENT POWER SYSTEMS
FOR AUTONOMOUS SUBMARINES
Herbert N i l s s o n
TheSubPower A B
Box 856, 201
80
Malmo,Sweden
ABSTRACT
U n i t e dS t i r l i n g
A B
(USAB), thew o r l d e a d e r
i nS t i r l i n ge x t e r n a lc o m b u s t i o ne n g i n ed e v e l o p m e n t
and Kockums AB a r e o i n t l y e s t i n g n a f u l l
s c a l e u b m a r i n e e s t e c t i o n a new
100
kW S t i r l i n g
en gi ne , he V4-275R, f o r theRoyalSwedish Navy.
The ngine i s i n t e g r a t e dw i t h a l i q u i do x y g e n
s t o r a g ea n d a c l o s e dcyc lecom bus t ion ys tem
i s
p r o v i d e d o ru n d e r w a t e rp r o p u l s i o n .
The
s u c c e s s -
f u ldeve lopm entof a pr es sur izedc o m b u s t i o n
s y s t e mu s i n gd i e s e l u e la n do x y g e n o r h e
S t i r l i n g e n g i n e has l e a d o h e n e x t s t a g e
-
a c o n t r a c t f o r i n s t a l l a t i o nof wo V4-275R en gin es
i n a l a r g e , manned d ive r ock- ou t ubm ar ine ,
t h e SAGA
I .
T h i s
500
toncom m er c ia lp r o to type ,
deve loped
i n
F r a n c e o i n t l y by
COMEX
and CNEXO,
is t o be compl eted by 1986.
I t
w i l l d e m o n s t r a t e
t h e a l l - u n d e r w a t e r ' ' o l u t i o n o rv a r i o u su n d e r s e a
t a s k s .
Miss ions of up t o 25 days ubmerged
w i l l
b e p o s s i b l e . T h eSwedish Navy in te nd oc o n t i n u e
t h e i rS t i r l i n gp r o g r a ma n d a s y s t e m o r e s t i n g
on nava l ubm ar ineshasb e e ncont r ac ted .
INTROWCTION
U n d e r w a t e ro p e r a t i o n s ,o f f s h o r e
as
well
as
mili
t a r y ,d e p e n d i g n i f i c a n t l yo n h e u p p l y o f
l a r ge m ountsof ne r gy .S ur f ace ndependent
e n e r g y - s u p p l y y s t e m s ,e . g . a c l o s e dc y c l eh e a t
eng inep lus noxygen to r age ,havedur ing he
y e a r sb e e n u b j e c t oc o n s i d e r a b l ed e v e l o p m e n t
e f f o r t s .N u c l e a r p o w e r y s t e m s o r a r g enava l
s u b m a r i n e sa r e ,h o w e v e r ,c u r r e n t l y h eo n l y
s y s t e m s , u l l yo p e r a t i o n a lu n d e r w a t e r .
The non- ava i lab i l i tyof om m er c ia l , om pac t
a i r - i n d e p e n d e n te n e r g ysou rce s n he medium
power ange , has a l s ob e e nh i n d e r i n ga n y i g n i f i -
c a n te v o l u t i o n o f u n d e rw a t e rau tonom ousof f shor e
o p e r a t i o n su s i n g u b m e r s i b l e s, u b m a r i n e sa n d
h a b i t a t s a s
well
as
when ai min g ore x t e n d e d
u n d e r w a t e r c r u i s i n g a n g e o r
naval
subm ar ines
of
medium
s i z e .
T h en e a r - t e r m o l u t i o n o r u r f a c e n d e p e n d e n t
s u p p l yo f a r g eq u a n t i t i e so fe n e r g y ou n d e r w a t e r
sys tem sw o u l dm os t ike ly
be
based on closed
c y c l eh e a teng ine s , among whi ch heS t i r l i n g
e n g i n ee m b o d i e s e v e r a lu n i q u e e a t u r e s , e c o g n i z e d
since many
y ea r s .
BASIC STIRLING TECHNOLOGY
T h e S t i r l i n ge n g i n e ,a n e x t e r n a l l yh e a t e de n g i n e ,
w i t h a c l o s e do p e r a t i n gc y c l e , was i n v e n t e d
i n 1816 y t h e Rever endR o b e r tS t i r l ing .The
e n g i n ehas many s imi la r i t ie s t o a c o n v e n t i o n a l
i n t e r n a lc o m b u s t i o ne n g i n e e . g . a d i e s e l e n g i n e ) .
However, i t d i f f e r s n h es e n s e h a th e a t i s
s u p p l i e d e x t e r n a l l y a n dc o n t i n u o u s l y o a working
g a s e . g .h e l i u m
o r
hydr ogen) ) ,w h i c h
i s
c o n t a i n e d
i n a c o m p l e t e l yc losed ys tem .
The p i s t o n s n a d o u b l e - a c t i n g S t i r l i n ge n g i n e
h a v ed u a l u n c t i o n s a n d e a c hp i s t o no p e r a t e s
s im ul taneous ly n wocyc les :
t h e
h o tupper
s u r f a c eo fo n ep i s t o nw o r k sw i t h i n h e
same
c y c l e
as t h e
c o l du n d e r u r f a c eo f h ea d j a c e n t
p i s t o n .T h ep r i n c i p l e so fo p e r a t i o n are shown
irl
f i g 1.
T h e o r e t i c a l l y , h eS t i r l i n gc y c l e h e r m o d y n a m i c
e f f i c i e n c y
i s
c l o s e o h a t of t h e d e a lh e a t
e n g i n e , . e . h eC a r n o t n g i n e .T h i s f f i c i e n c y
l e v e l e q u i r e s ,h o w e v e r , a q u i t eh i g ho p e r a t i n g
t e m p e r a t u r eo f h ew o r k i n gg a s o g e t h e rw i t h
a h i g hw o r k i n gg a sp r e s s u r e .H e n c ea v a i l a b i l i t y
ofadvanced
materials
t echnology i s n e c e s s a r y
f o rh i g hp e r f o r m a n c eS t i r l i n ge n g i n e s .T h i s
s t a t u s
was
n o te s t a b l i s h e d u n t i l h e
l a t e
1 9 3 0 ' 8 ,
a f t e r s i g n i f i c a n td e v e l o p m e n tw o r k
c a r r i e d
o u t
bp N . V . P h i l i p s n T heNethe r lands .
THESUB POWER AB
U n d e r w a t e ra P p l i c a t i o n so f h eS t i r l i n ge n g i n e
h a v eb e e ne x t e n s i v e l ys t u d i e da n dd e v e l o p e d
j o i n t l y by U n i t e dSt ir l i ng and Kockums, t he
m ain ubm ar inecont r ac tor o r heR o y a lS wedish
Navy.
For the
over a l lcom m er c ia l i za t ion ' o fUnder wa te r
EnergySystems,
based
o nS t i r l i n g e c h n o l o g y ,
Kockums
A B
a n dU n i t e dS t i r l i n g
A B
i n
1982
formed
a jo i nt l y owned ompany, th e SubPower
A B ,
t h u s
i n t e g r a t i n g
the
Kockums unde rwa ter yste msw i t h
t h eU n i t e dS t i r l i n gu n d e r w a t e re n g i n e e c h n o l o g y .
UNITED STIRLING
AND
CURRENTROGRAMS
U n i t e d S t i r l i n g A B ( US AB) , loca ted n Malmt),
Sweden, was f o u n d e d n1 9 6 8 , t a r t i n g i t s deve lop-
mentwork as a l i c e n s e eo f N . V . P h i l i p s . T h e
company i s now a s u b s i d i a r yo f h e FFV g r o u p ,
b e i n g a l a r g e w e d i s hndu s t r i a l r oup , owned 1
42
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by thegover nm enc , o r hedevelo pment nd manu-
f a c t u r eo fa d v a n c e dd e f e n c e y s t e m s .
T h e i n i t i a ld e v e l o p m e n t a t USAB was basedon
s i n g l e - a c t i n g a d i s p l a c e re n g i n e s ,wi th a rhombic
dr ivem echanism .Gener a l om plex ib i l i ty nd
d isadvantages nwe igh t ,d im ens ions ndm anuf ac -
t u r i n gc o s t s n i t i a t e d USAB t o u r n n t o h e
double - ac t inge n g i n econcep t .
A
numberof uch
e n g i n e sh a v eb e e nb u i l t , o r m i n g h eb a s e o r
t h e
USAB
cur r en tm a in ng inepr ogr am s , woof
t t e mw i t h4 - c y l i n d e rd o u b l e - a c t i n gc l u s t e rc o n -
f i g u r a t i o n s ,nom ina ted 4-95 and4-275, nother
onebasedu p on a s i n g l e - a c t i n gd u a lc y l i n d e r
\ ' - conf igur a t ionnom ina ted heV160- engine .
The L:SP.B en g i n e s2 r eh a v i n gp e r f o r m a n c ed a t a
e q u i v a l e n t o h o s eo fa d v a n c e dd i e s e le n g i n e s
ir: t h e r n e d i u npower ange .Tota l e s t ing im e
f o r a l l USAB enginesondynamometers nd n
demonstrat ionprograms xceeds 2 4 0 , 0 0 0 h o u r s ,
w h i l e m ax imun t e s t i n g i n e o r a n n d i v i d u a l
e n g i n e x c e e d s1 Q . 0 0 0h o u r s .A d d i t i o n a l l y , e p a r t e
c o 2 p c J n e n t e s t i n g i s b e i n gper f or m edon pec i f i c
cooponents uch
as
s e a l s ,p i s t o n i n g s , e g e n -
e:ato-s nd he at er s. Wore than100 ,000hour s
o f e p a r a t ec o r c p o n e n t e s t i n gh a v e i g n i f i c a n t l y
C o n t r i b l J t e d oa no v e r a l l m p r o v e de n g i n e r e l i -
a b i l
i t ? .
S t a t i o n a r ya p p l i c a t i o n s o rp r o v i d i n ge l e c t r i c i t y
i r o n o l a re n e r g yc o n v e r s i o na n d o r e r v i n g
a s h epr im e m over in e s iden t ia lW A C - s y s t e m s
a r e h ec u r r e n t v o l u me o m m er c i a l r e a s o r
:he USAB en gi ne ys te ms . For sys temsdevelopment
a n dc o m e r c i a l i z a t i o n o f h e o l a ra p p l i c a t i o n ,
USAB
i s
cooper a t ingwi thXcDonne l lDouglas ,
whi le heHVAC- appl ica t ion i s h e a v i l y u p p o r t e d
by t h e G as R e s e a r c h n s t i t u t e .
T h eu n d e r w a t e ra p p l i c a t i o n so f h eS t i r l i n g
e n g i n eh a v eb e e n t u d i e da n dd e v e l o p e d i n c e
t h ee a r l y1 9 7 0 ' s ,c o n s i d e r e d ob ea na t t r a c t i v e
a r e a o re z r l yc o m m e r c i a l n t r o d u c t i o no f h e
S t i r i i n ge n g i n e sc h a r a c t e r i z e d by u n i q u e y s t e m
f e a t u r e s .
BASIC STIRLING UNDERWATER ENGINETECHNOLOGY
USAB ha sbeenwor k ingw i t hunder wa te ra p p l i c a t i o n s
f o r m o r e h a n1 0y e a r s o i n t l ywith Kockums
and Comex. Ma rs ei l l e ,
a
w o r l d - l e a d i n go f f s h o r e
technology ompany.Hybr idpowerplants or
n e d i u m i z e dn a v a l u b m a r i n e sh a v eb e e n u b j e c t
tcj deve lopm enta sw e l l as ener gy sys tem s or
o f f s h o r e u b m a r i n e s .h a b i t a t s n d u b m e r s i b l e s.
T h e S t i r l i n gc y c l ee n s u r e s o wc y c l i c o r q u e
v a r i a t i o n sa n d o wn o i s e / v i b r a t i o n e v e l sc o m p a r e d
t o h o s eo f e c i p r o c a t i n g n t e r n a lc o m b u s t i o n
e n g i n e s p a r a m e t e r so fg r e a t m p o r t a n c e o r
nzva l ubm ar ines .The om bus t ionpr es sur eof
t h eS t i r l i n ge n g i n ec a nb e a i s e da b o v e h a t
sf a m b i e n t n v i r o n m e n t , . g . nu n d e r w a t e r p p l i c a -
t i o n s c o a p r e s s u r e b o v e h a to f h e u r r o u n d i n g
w a t e r .H e n c e , h e n g i n e y s t e m a no p e r a t e
subm er ged o a dep thofappr ox .
300
m withno
r e e d o re i t h e ra ne x h a u s tg a sc o m p r e s s i o n o r
a d i s s o l v i n gs y s t e m
f o r
t h ee x h a u s tg a so fs i g n i f i -
c a n tv o l u m e n d o m p l e x i b i l i t y s e e ig . 2
F o rc o n t r o lo f h ep r e s s u r i z e dc o m b u s t i o nU s i n g
p u r eo x y g e n q u a l o n d i a b a t i c
flame
t em per a -
t u r eof 4000
C ,
e x h a u s tg a s e c i r c u l a t i o n s e e
f i g .
3
i s
used . A m i c r o p r o c e s s o r e m o t e l ym o n i t o r s
t h ee n g i n ea n dp r o c e s sV a r i a b l e 6 n h eb a s i c
o p e r a t i o nm o d e s .
0
THE 4-95 PROJECT FOR
A
STIRLING
POWERED SUBMERSIBLE
T h ec u r r e n tS t i r l i n gu n d e r w a t e r e c h n o l o g ya t
USAB or i gi na te s rom a p r o g r a m h a ts t a r t e d
1979-80 form o d i f i c a t i o nof he 4-95 eng i ne ,
i n
a
j o i n tp r o j e c twi th Comex I nd us t r i e s , a i m i n g
f o r
a
power sou rc e or manned subme rs ibl eso f
e x t e n s i v ee n d u r a n c e .
W i t h i n h e 4-95 p r o j e c tc e r t a i n " k e y u n c t i o ns "
f o r
a s u c c e s s f u lu n d e r w a t e rp o d i f i c a t i o no f
t h es t a n d a r de n g i n ew e r eq u a l i f i e dw i t hs a t i s f a c -
t o r y r e s u l t s :
Over pr es sur ecom bus t ion
- C o m b u s t i o ng a s e c i r c u l a t i o n
Oxygen con t r o l ys tem
Exhaus tv a l v ed e s i g n
Ar r angem enta n a l y s i sve r suspr e
d e n s i t y o b j e c t i v e s
- s e t n e r g y
The 4-95powermodulebecamedeveloped tos u p p o r t
a i r - i n d e p e n d e n tu n d e r w a t e ro p e r a t i o n su s i n g
d i v e r o c k o u t u b m e r s i b l e s f i g .
4 ) .
The ombus-
t i o np r e s s u r e w a shencechosen o
30
b a r ,w h i c h
m a t e sw i t h h e u r r o u n d i n gw a t e rd e p t ha tc u r r e n t
limit f o ro p e r a t i o n a l o f f s h o r ed i v i n g
( 3 0 0 rn .
Them oduleh a da ne lec t r i co u t p u tof
20
kW,
t o g e t h e rw i t h u p p l y
of
h o twa te r 50°C) o
beused
f o r
d i v e r s ' n d o m p a r t m e n t s 'h e a t i n g .
T H E
SWEDISH NAVY STIRLING SYSTEM PR O G R A M
T a c t i c a lb a c k g r o u n d
Of c r i t i c a l m p o r t a n c e o r h ec o m b a te f f i c i e n c y
of he onvent io na l ubm ar ine
is
t h ec a p a b i l i t y
f or ong ubm er ge d ndur anc e : . e . maximum in te r -
v a l sb e t w e e n h e n o r t i n g / r e - ch a r g i n gp h a s e s .
The e-charge nergy
i s
p r o v i de d b y t h e u b m a r i n e ' s
d i e s e lg e n e r a t o rp l a n ta n d h e n d u c t i o na i r
i s
l e d o h ed i e s e le n g i n e s h r o u g h a s n o r t
m a s tp e n e t r a t i n g h e u r f a c e .T h e x p o s e d n o r t
mast w i l l t h e r e f o r e show t h e u b m a r i n e ' s o c a t i o n
f o r a q u i t e u b s t a n t i a lp e r i o do f t ime.
C o n s e q u e n t l y , h e n o r t i n g u b m a r i n e i s v u l n e r a p l e
t od e t e c t i o na n d u b s e q u e n ta t t a c k s .
To improve he ubmerged ndurance imply by
a d d i n gm o r eb a t t e r i e s w i l l , however ,qu ick ly
l e a d oa nu n a c c e p t a b l eg r o w t ho f h e u b m a r i n e
s i z e ,d u e t o t h e a i r l yp o o re n e r g yd e n s i t y
o f h ec o n v e n t i o n a l e a da c i db a t t e r i e s ,d o m i n a t i n g
as t h ee n e r g y t o r a g e o ru n d e r w a t e rv e h i c l e s .
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T h e i n t r o d u c t i o n of anener gydenseand a i r -
independent heat enginebasedpowerconver s ion
systemmeanshence a p o t e n t i a l o r a s i g n i f i c a n t
im pr ovem entof he ubm er gedendur anceof he
subm ar ine .
TheSwedish Navy Sti r li ngd e v e l o p m e n tp r o g r a m
TheRoyalSwedish Navy and Kockums ha ve or
a n x t e n s i v ep e r i o do f i m ep e r f o r m e d
t e s t s
a n d t u d i e so fa i r - i n d e p e n d e n tp o w e rC o n v e r s i o n
s y s t e m s o r u b m a r i e s . A number ofp r o j e c t s
a n dprototyse work has b e e nc a r r i e do u t e g a r d i n g
h e a t n g i n e s s h e l o s e d - c y c l ed i e s e l n g i n e
a n d h eS t i r l i n ge n g i n e , u e lc e l l s as w e l l
a sh i g he n e r g yb a t t e r i e s .
Th e S t i r l i n g e c h n o l o g y was e v e n t u a l l y d e n t i f i e d
a s h a v i n g h eb e s tn e a r - t e r mp o t e n t i a l as an
a i r - i n d e p e n d e n t p ow er s o u r c e ,a n d
was
s u b s e q u e n t l y
se le c t ed by theRoyalSwedish Navy f o r a f u l l
s ca le ys te r nsdeve lopm ent .
An underwater nginedevelopmentprogrambased
on thew e l lp r o v e n
4 - 2 7 5
s t a n d a r dS t i r l i n ge n g i n e
was
i n i t i a t e d1 9 8 2 , n t e n d e d o r n t e g r a t i o n
w i t h a LOX s y s t e m ,u s i n gw e l le s t a b l i s h e dc r y o g e n i c
technology r om he ACA Cryo Company in Sweden.
The 4 - 2 7 j e n g i n e f i g s . 5 and
6 )
means n ngine
w i
h
f o u r c y l i n d e r san d a swept volume f 75
CT'. T h e c y l i n d e r s are a r r a n g e d n a V g i v i n g
a n o i s e a nd v i b r a t i o n e v e l o f a very owmagni-
tude ,m ee t ing he eve r edem and s rom a Navy.
A
s i l e n te n v i r o n m e n t i s a l s oo fg r e a t m p o r t a n c e
i n a c i v i l i a n u b m a r i n e ,b o t h o r h ec r e w ' s
c o m f o r ta n d o r h e e l i a b i l i t yo f h eh y d r o -
a c o u s t i c o m n u n i c a t i o n y s t e m s .
The om bus t ionpressure i s kept 20-30
b a r ,
why
t h ee g n i n ec a n n i t i a l l yope r a te ubm er ge d down
t o 300
m . D e e p e ro p e r a t i n gd e p t h s , o a y 6 00 m
could be ach ieved
by
a d d i n g x h a u s tgas com-
2 r e s s i o no fo n l ym a r g i n a lp r e s s u r e a t i oa n d
hen ce ns i gn i f i c an t power onsum pt ion .
The 4 - 2 7 5 e n g i n ea n d h e LOX sys temhavebeen
e x t e n s i v e l y e s t e dd u r i n g 1 9 8 4 n dwas n tegr a ted
e a r l y 1 9 8 5 . The omplete ys tem i s now undergoing
s u b s e q u e n to p e r a t i o n a l e s t i n g , n s t a l l e d n
a f u l l c a l e u b m a r i n e e c t i o n f i g s .
7
and
8 ) . The LOX sys tem ankandpip inga r r angem ents
a r e sh own i n i g . 9 .
Thenava l ubm ar ine ng ine ys tem r r angem ent
Thenormal ubmerged ruis ing mode of he onven-
t i o n a l u b m a r i n e i s s i l e n t , c o n o m i c a l n d l o w -
s p e e d u r v e i l l a n c e . From t h eSwedi sh Navy eva lua -
t i o n sa n dpr edes ign wor k was hence ound t h a t
a su i tab lec o n c e p tc o u l db e a hybr idpower onver -
s i o n y s t e m . m e a n i n ga d d i n g o h ew e l l - e s t a b l i s h e d
c o n v e n t i o n a lb a t t e r y
system
a na i r - i n d e p e n d e n t
com ponent , a t a l o w e r e v e l u f f i c i e n t o ra n
a p p r o p r i a t ea i r - i n d e p e n d e n t u b m e r g e dc r u i s i n g
mode.The ir - independentpower onvers ionmodule
t h e r e f o r ec a nb ed e s i g n e d o r l owp o w e r g e n e r a t i o n ,
s i nc e t h i s w i l l be s u f f i c i e n t os u p p o r t t h i s
p a r t i c u l a r m o de ,w h i i e h eb a t t e r ye n e r g ys t o r a g e
w i l l be u s e d o r mo de s r e q u i r i n gh i g h e r p o w e r
o u t p u t ss u c h as o f f e n s i v ea n de s c a p i n gm a n o e u v r e s .
The dd-on oncept i s a p p r o p r i a t e as a f i r s t
g e n e r a t i o nh y b r i d y s t e m ,a n da l s oc o v e r s
t h e
caseunderwhich- a c o n v e n t i o n a l u b m a r i n e ,a l r e a d y
i nc o m m i s s i o n ,c o u l db e e t r o f i t t e d w i t h an
add- on hu l ls e c t i o nc o n t a i n i n g h e e n t i r e
a i r -
i n d e p e n d e n t y s t e m s e e i g .1 0 ) .F u e lo i l i s
p r o v i d e d o h ee n g i n e r o m h eo r d i n a r yb u n k e r
oil supplyonboard ndoxygen i s s t o r e d n
one o r s e v e r a l i q u i f i e do x y g e ns t o r a g e a n k s .
An
a d d - o n y s t e mc a s e t u d i e d o r a 1000 tons
c o n v e n t i o n a l u b m a r i n em e a n s w oS t i r l i n gg e n e r a t o r
s e t so fa b o u t 70 kW e a c hw i t ha u x i l i a r i e sa n d
a
LOX sys tem.Thepower eve l i s s u f f i c i e n t
t os u p p o r t h eq u i e t ,e c o n o m i c a l u n n i n g mode
i n c l u d i n g h e e l a t e d a u x i l i a r y p o w e r e q u i re m e nt s .
The ubmergedendurance
w i l l
mainlydependon
t h e a m o u n to f t o r e do x y g e n , h e r e f o r e h e LOX
t a n ks i z e s
w i l l
d e f i n e h ed i m e n s i o n so f h e
a d d - o nh u l ls e c t i o n .
The ubmergedenduranceof
a
h y b r i d
powered ubmar ine
An app r ec i a t i ono f t he c u r r e n te n e r g yd e n s i t y
i s g i v e n r o m h e e l a t i o n s h i p h a t a n n c r e a s e
of he ubm a r ine eng t h by ome 10%w i l l more
thandouble he ubmerged owpowerendurance.
F i g . 11 i l l u s t r a t e s a f i c t i o n a lo p e r a t i o n a l
p r o f i l eo f a c o n v e n t i o n a l u b m a r i n eh a v i n ga n
a i r - i n d e p e n d e n tS t i r l i n gs y s t e ms u f f i c i e n t o r
low peedpr opuls ion .The ubm ar ine
w i l l
commence
o p e r a t i o n sw i t h u l lo x y g e n t o r a g ea n d h e
b a t t e r y u l l yc h a r g e d .T h eo p e r a t i o n s t a r t s
w i t h
t h e
add- on ys tem unning - n o b a t t e r y
d i s c h a r g e - u n t i l h es e c o n dday, when a t a r g e t
i s engageddur ing 3 h o u r so fb a t t e r y u n n i n g
( d i sch a r g e ) . Upon com ple t ionof a r ge t ngag em ent
t h e p o w e rc o n v e r s i o n e t u r n s o h ea d d - o n y s t e m
f o r h en e x t u r v e i l l a n c ep e r i o d ,p r i o r o
a
new targetengagem entphase ,and
s o
on .
T h e b a t t e r y i s c o n s e q u e n t l yd i s c h a r g e d ns t e p s ,
and i s i n t h i s exam pled ischa r ged down t o h e
t a c t i c a l e s e r v e e v e l o f 50 a f t e ra b o u tn i n e
d ay s. By t h i s
time
t he oxygen i s consumed nd
t h es u b m a r i n e e v e r t s o a nor m alconvent iona l
b o a t .T h i sh y b r i d u b m a r i n e ,h o w e v e r ,h a sb e e n
i n h eo p e r a t i o n a la r e an i n ed a y s ,a n d
has
conduc t -
e d f o u r a r g e te n g a g e m e n t sw i t h o u te x p o s i n g
t h e s n o r t mast.
ContinuedSwedish Navy Program
TheSwedish Navy in te nd oc o n t i n u e h e i rS t i r l ' i n g
programand a s y s t e m o r e s t i n go nn a v a ls u b -
m ar ines has b e e nc o n t r a c t e d .
The ys tembas ica r r angem ent w i l l be
i n
accor dance
w i t h h ea b o v ed e s c r i b e d a d d - o n "c o n c e p t .
The tes tp r o g r a m
i s
i n t e n d e d op r o v i d e h e
q u a l i f i c a t i o n e q u i r e d o r h e Navy t o e c i d e
44
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u po n f u t u r e u b m a r i n e sh a v i n g n n t e g r a t ea
S t i r l i n ga i r - i n d e p e n d e n tp r o p u l s i o n y s t e m .
AUTONOMOUS OFFSHOREUBMARINES
3:Sferentf concepts f o r of f shor e ubm ar inesh a v e
3 u r i n g t h e y e a r sb e e np r e s e n t e d np r o j e c t s
frorn LestGer m any ,Franc e, USA, Swe den , tc .
a s
a
s o l . J t i o n o
t h e
pr oblensp o s e d by o f f s h o r e
o p e r a t l o n s nd e e pa n dh o s t i l e
wate rs .
Themain
o b s t a c l e o ? a l l t h e s ep r o j e c t sh a s ,h o w e v e r ,
3 e e n h e1 i r : i t e d ? e r a t i o n a l
t ime
when submerged.
3 u f f l c i e n t n e r g y o rw o r k i n gp e r i o d so f1 0 - 2 0
zays ilkmerged h a s 5een t h e c r u c i a lp r o b l e m ,
: - p c s s i b l e o o l v e w i t h t r a d i t i o n a l e c h n o l o g y
. d i e s e l - e l e c t r i c y s t e m s o g e t h e rw i t h e a d - a c i d
3a tce : i e s i .
Tne 5 t i : l l n T y s t e n a c i l i t i e s ,however , now
s,uf:^ic:ent nergy
f o r
s u b m a r i c e s n dh a b i t a t s
ca2ab le fwor k ing
a t
g r e a td e p t h s o r w o w ee ks
- -_o r e , i n d e p e r d e n t o f s u r f a c e c o n d i t i o n s .
THEAGA PEOJECT
Background
r : r i ar ei a l r e a d y1 9 6 7 , t h e A r g y r o n e t e ,
l a t e r
t h e S A G A I s u b m a r i n e ,m e a n t h e i r s to p e r a t i o n a l
2 ? p r o a c > oe n a b l e t c work n th eb o t t o no f
:he $ e e p e a r o m a s e l f - c o n t a i n e d , p d e p e n d e n t ,
s u p p l yb a s e . r e e r o m h e u r f a c e o n d i t i o n s .
T h e c k m a r i n e i t c e d w i t k . a s u f f i c i e n t l y a r g e
e n e r g y e s e r v e o u s t a i n a l o n g - d i s t a n c e u b m e r g e d
t r i p t 9
i t s
w o r k i n g i t e , h e n work t h e r ew i t h
2 l v e r sa n d / c r o b o t s o r
a
s i g n i f i c a n tp e r i o d ,
and hen ox eback o
i t s
b a s ew i t h o u t . u r f a c i n g ,
cc':;d be n de al ol ct io n.H o w e v e r , e p e n d i r g
s c l e l y
o n
a l e a d - a c i db a t t e r y a s e n e r g y t o r a g e ,
t h eo r l g i r a l c b m a r i n e o n c e p t
was
f o u n dn o t
t c ,
t e
u s a b l e n d o n s t r o c t i o no f h e u b m a r i n e
'xas nct oir .ple te 3.
Ir. 1 9 8 2 , COXEX d e c i d e d o e - i n i t i a t e h i sp r o j e c t
o r e s 2 c n d
t o
new c h a l l e n g e s a c i n g h eo f f s h o r e
c : l
i n d u s t r y ,u t i l i z i n g :he s i g n i f i c a n t n d u s t r i a i
3 e v e l o p - . e n t no n eo f h ek e y e c h n o l o g i e s o r
a r u t z n o n o u s u b m a r i n e ,
i . e .
EnergyConvers ion.
..-.e
-.ai?. da t a f o r :he SAGA s u b m a r i n e s e e i g .
1 2 I
a r e
a s f ol l ows :
.
S - ? x a r i n e :
Length s...erall
2 6 . 0
I
B r e a d t ho v e r a l l
7 . 5
Submergeddisp lacem ent
5 L 5
t o n s
D p e r a t l o n a ld e p t h
6 3 0
n
Crew:
b l a i n crew
6men
Dive rs
6 men
The SAGA su bm ar in e4 - 2 7 5S t i r l i n g c g i n e n d
o x y g e n t o r a g e u r r e n t r r a n g e m e n t s r e h o v n
i n i g s .
I 3
and
1 4 .
The SAGA sub ma ri ne
will
b ea b l e oc a r r yo u t
a n d / o r u p p o r t a v a r i e t yo f c b s e so f f s h o r e
t a s ka n do t h e ro i l - r e l a t e da c t i v i t i e s :
Maintenance
of
w e l l h e a da n d u b s e ap r o d u c t i o n
s y s t e m s
H i g h - r e s o l u t i o n e i s n i co p e r a t i o n so np o s s i b l e
d r i l l s i t e s
- - G e o l o g i c a l a m p l e - t a k i n g by r o t a r y c o r i n g
C o n s t r u c t i o na s s i s t a n c e nh y p e r b a r i cw e l d i n g
o p e r a t i o n s
P i p e l i n e u r v e y s
O p e r a t i o no f o b o tv e h i c l e sa n d y s t e m sa s
ROVs, r e m o t e e l e n a n i p u l a t o r s,m o d u l e ' s e p l a c e -
ment o r r e p a i re t c . . .
THE SAGA SUBt4ARINEDESIGN MISSIGKS
T h e o l l o w i n k e s u l t sh a v eb e e ng a i n e d r o m
p o s s i b l ea p p l i c a t i o n s n e r n so fa u t o r o x ya n d
e f f i c i e c c y by t h e SAGA I subm ar ine .
T h e s e e s u l t sh a v eb e e n i m u l a t e d
f o r
t 'wo precise
o p e r a t i o n s , a l l e d d e s i g nm i s s i o n s "d e f i n e d
f r o ma c t u a lc o n d i t i o n s .
T h e f i r s tm i s s i o n
( s e e
f i g . 15 , f o r e s e ed i v i n g
o p e r a t i o n s
a t
150 n a u t i c a l miles f r o 3 a b a s e .
Thebasenaybe STAVANGER, and hewor k s i t e
CORMOR4KT FIELD. The t o t a l r a n s i t i m ew o u l d
be76hour s
a t
k n o t sw i t h o u t u r f a c i n g .T h e
ener gy nd t h e gasonboar d l lowm or e han 200
h0.x- s
o fd i v e r n t e r v e n t i o n .
T he t o t a l r i s s i o nd u r a t i o nw o u l db ea b o u t 10
d z y s .
T h e e c c n dn i s s i s c ( s e e f i g . 16j, c o n c e r n s
a
s 'urvey a t 100 n a u t i c a ln i l e s r o m a base.The
base
may be PALERMO i n S i c i l y 2nd t h eO p e r a t i n g
z o n e h eS i c i l i a nS t r a i t s . The t o t a l r a n s i t
t imewooldbe 5 0 h o w s a t k n o t sw i t h o u t u r -
f a c i n g .T h e u b n e r s i b l e ' s u t o n o m y l l o w s 190
n a u t i c a l mi l e s a t
1
k n o t o b e u r v ey e d .
The to ta lm i s s i o n u r a t i o nw o u l d e b o u t 10
day
s
.
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The SACA pr og ra mm i le s to n e s
Th em a jo ro b je c t i v e s
of
t h e SACA prog ram
are
n o to n l y e c h n i c a lb u ta l s op s y c h o l o g i c a lb e c a u s e
t h i s p r o j e c t n t e n d s od e m o n s t r a t e h eo p e r a t i o n a l
f e a s i b i l i t yo fa no f f s h o r e u b m a r i n ea s a b a se
f o r deep human di vi ng down to 450 m .
T h e
SAGA
program
w i l l
c o s ta p p r o x i m a t e l y
35
H i l l i o nFre n c hFra n c sa n dc o v e r so v e r 4 y e a r s
1982-1986). Commerc ia lopera t ion
are
s c h e d u l e d
t o commence 1987/1988.
\
THE
SAGA
I ENERGY SYSTEM
T h e
ene rg y ys te m or he SAGA
I
i s n e a r l y d e n t i -
c a l o h e y s t e mb u i l t a n d t e s t ed f o r h eR o y a l
Swedish Navy and nclude s wo 4-275 S t i r l i n g
e n g i n e s n t h e power ange
of
100 kW andwo
l i q u i do x y g e n a n k sg i v i n ga ne n e r g y e s t o r a g e
c a p a b i l i t yo f
12,000
kwh a l l o w i n g op e r f o r m
m i s s i o n so fu p o 3 weeks ubmergeddepending
o n th ep r o f i l e . T h eLOX-system f o r h e SAGA
i s a l s o a desig n rom ACA-Cryo, C othen burg.
THE V160
SYSTEM
A powermodule f 7 kW w i t h d d i t io n a lh e a t
i s now designed,b a se d e u p o n h e V 160 e n g in e ,
i n t e n d e dp r i m a r i l y
f o r
p o w e r u p p ly od iv in g
b e l l s nd h e n c ep ro v id in g h e n
w i t h
energyau-
tonomy.The ngine i s c u r r e n t l yp l a n n e d ob e
i n s t a l l e d n
a
p o d i n t e g r a t i o n w i t h t h ed i v i n g
b e l l s e e i g .
171.
ENERGY SYSTEMS
BASIC
ARRANGEMENTS
A
n e a r - t e r m a p p l i c a t i o n f o r t h e 4-95 systemmeant
anEnergySupplymodule f o r submersib les , why
a r r a n g i n g h ee n g i n ea n d
t h e
f u e l a n k s np o d s
s imilar
t o h o s e o rs t a n d a r d
b a t t e r i e s ,
was
found
o p t i m a l ,h a v i n g a d i a m e t e ro f
0.8
ma l e n g t h
of
3.5 m . G l o b a lo x y g e n a n k sa n d o f t u e l a n k s
werechosen .The ystemdryweight was approx.
3 t o n s , when su b m e rg e d h e y s t e mw a sc lo se o
n e u t r a l l yb u o y a n t .S e r v i n g as a Genera lUnderwate r
En e rg ySu p p lySy s t e m h ee n g in ea n d h e u e l
s y s t e r r :m ig h tb ea r ra n g e dd i f f e re n t ly .
Theoxygen torag e may i n g e n e r a l b e e i t h e r as
h i g hp r e s s u r e
300
b a r ) g a s
or,
when
a
l a r g e
e n e r g y t o r a g e
i s
r e q u i r e d ,
as
l i q u i do x y g e n
L O X ) .
For a ne n e r g y t o r a g eo f 200 kwh e l e c t r i c
e n e rg y ,w h ic h was c o n s i d e r e do p t i m a l for d i v e r
lo c k -o u t submersibles, t he oxygenwould be o p t i -
m a l l ys t o r e d
as
h i g h p r e s s u r e
gas.
Th e y s t e mconceptm e a n sa l so u p p ly
of
h e a t o
d i v e r s ,u t i l i z i n g h e e j e c t e dh e a t r o m h e
e n g i n ec o o l e r , a t i s f y i n gd i v e r s ' a s well
as
c o m p a r t m e n th e a t i n gn e e d s . n t e g r a t i o nwith a
s u b m e r s i b l e e a t i n g y s t e m i s show n in i g . 18.
T h e a b o v ea r r a n g e m e n tc o n s i d e r a t i o n s o r h e 4-95
s y s t e ma r eg e n e r a l ,w h i c hm e a n s h a ta n yo u t b o a r d
zrrzngementwould b e based on a pode n c a p su la t i o n
o f h ee n g i n e a n d a s t r e n g t h / w e i g h to p t i m i z e d
o x y g e ns t o r a g e ,e i t h e r ng a s e o u s
or
l i q u i dp h a s e ,
d e p e n d i n g o f h e e n d u r a n c e e q u i r e d o r h e
system.
I n b o a r d n s t a l l a t i o n sc o u l d b ea r r a n g e da c c o r d i n g
t o w ha t
has
b e e n co ns id er ed or he Kockums
h a b i t a t
p r o j e c t ,h a v i n g
a
4-275
St i r l ing-LOX
sy s t e m
o r
similar
t o h ec o n c e p t u a ld e s i g n o r -
a currentn a v a lsu b m a r in ee q u ip p e dw i t h
a 4-275
S t i r l i n gc r u i s i n gs p e e dp r o p u l s i o nu n i t ,s e e i g s .
19 and 20
POWERAUTONOMOUS ROV'S
The useofROV-vehic les
has
g r o w n s i g n i f i c a n t l y
o v e r
t h e
r e c e n ty e a r sa n d s e v e r a lc o n c e p t se x i s t ,
r a n g in g ro m
small,
l i g h to b s e r v a t i o n . v e h i c l e s
t oh e a v y , o p h i s t i c a t e d , p e c i a lp u r p o s ev e -
h i c l e d w o r k y s t e m s .
A n u m b e ro fp ro j e c t s e g a rd in g r e e w im m in g ve-
h i c l e s ,e . g . o ru s e n a r c t i c
areas ,
a r ec u r r e n t -
l y s t u d i e d a n d p r o t o t y p e s y s t e m s h a v e b e e n b u i l t .
The "f re e swimming" oncept ssumesuse
o f
s e v e r a l
a d v a n c e d e c h n o lo g ie s , n c lu d in go n -b o a rde n e rg y
sforage .Advanced
ba t t e r i e s are
c u r r e n t l y h e
m a inp o w e r o u rc e o r h e r e e w im m in g ROV, b u t
h e a te n g i n e s are s t u d i e da n d o f f e ra n n t e r e s t i n g
p o t e n t i a l , p a r t i c u l a r l y o r h e h e a v y v e h i c l e s ,
r e q u i r i n g s a y
150-300
kwh per m i s s i o n
o r more.
T n e S t i r l i n g e n g i n e s y s t e m for
ROV
power upply
means a pod i n s t a l l a t i o n
for
t h ee n g i n e , similar
t o h ea r r a n g e m e n t
for
t h e
4-95
p r o l e c t f i g .
4 )
a n d h e V160 ( f i g . 17) t o g e th e rw i t ha no x y g e n
s t o r a g eo f e a s i b l ed e s i g n e . g .a d v a n c e d
GRP-
s t e e l h i g h p r e s s u r e b o t t l e s o r s p e c i a l l y d e s i g n e d
s p h e r i c a lh i g hp r e s s u r e a n k s ) .
I n o r d e r o o w e r h e s y s t e m
wet
w e i g h t ,
as
many
as
p o s s i b l e
of
t h e e n g i n e a u x i l i a r i e ss h o u l d
be
a r r a n g e d o u t s i d e h ee n g i n e p o d .
Power ystemsperformances are g i v e n n a b l e
1
while
power ystemweights
are
r a n g in g ro m
approx.
350
kg
f o r
t h e
V160
e n g i n ew i t hp o d f i g .
17) t oa p p r o x . 1600 k g f o r
a
4-275 e n g i n e y s t e i
w i t h pod.The boveweight estimates assume
a
w e ig h t -o p t im iz e dp o d -d e s ig na n dd o e sn o t n c lu d e
t h eo x y g e ns y s t e m h a th a s o b e d e s i g n e d n d i -
v i d u a l l y o r e a c hv e h i c l e p r o j e c t a n d m i s s i o n
p r o f i l e .
46
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Ta31e
1 .
Power system cerformance
A e , ~ r r e s ? o n b i r ge n g i n eo v e r a l le f f i c i e n c y
i s
G 2 7 5 : 3 8 c o r r e s p o n d i n g o 820 g 0 /kwh
2
CONCLUSION
Thenear - term ys tem echnology
f or
s u p p l y i n g
l a r g eq u a n t i c i e s
o f
e n e r g y ou n d e r w a t e r y s t e r n s ,
v l t . i :n oxm er c ia l r i t e r i a nc1udi r . gw e i g h t n d
.::l-ce s?:imization,
i s
l i l c e l y o be b a s e d on
: l oseC cyc le kea: eng i ces .
;:,cng a'.'ailable h e a t e n g i n e s h eS t i r l i n ge n g i n e
e n 5 ~ 6 1 e s
n i q o e e a t u y e s , . g . f f i c i e n c y n d
a pc'xe:
t c w e i g h t a t i oe q u i v a l e n t o
a
d i e s e l
e r g i r e ,n c i s ea n dv i b r a t i c n e v e l sm e e t i n gn a v a l
sc3-ar :ce eqlJ i-ements , a fu l l yc o n t r o l l e dp u r e
sxyger :p r es sur ized om bus t ion nd a c om pa ct t o t a l
s y s t e ? a r - a n g e m e n t .T h eS t i r l i n ge n g i n eh e n c e
z o n s t i t u t e s a h i g h l ya p p r o p r i a t ee n e r g yc o n v e r t e r
Tzr ; I n d e r w a t e ro p e r a t i o n s e q c i r i n ge x t e n s i v e
sur f ace ndeuendent n dur ance .
W e l l - p r o v e nU n i t e dS t i r l i n ge n g i n e sha ve now been
a d a p t e d ou n d e r w a t e ro p e r a t i o n s , h u sp r o v i d i n g
s u r f a c e n d e p e n d e n te n e r g y u p p l y ou n d e r w a t e r
s y s t e m s ,o f f s h o r e
a s
w e l l as m i l i t a r y .
Kockums AB an dU n i t e dS t i r l i n gh a v e n t e g r a t e d
t h e i r n d i v i a u a lu n d e r w a t e rs y s t e n sa n de n g i n e
t e c h n o l o g i e sw i t h i n a j oi n t l y owned ompany,
the S ubPower
A B ,
w i t ha c c e s s ou n d e r w a t e r i q u i d
o x y g e n y s t e n s e c h n o l o g y r o m h e AGA
Cryo
A B .
TheS ubP owerS t i r l ing- LOX ys tem s , u r r en t ly
b u i l t f o r theRoya lSwed ish Navy and f o r Comex
will
f a c i l i t a t eu n d e r w a t e ra u t o n o n o u sd e e pw a t e r
sys tem s , apab leofw o r k i n g
or
weeks , ndependent
of
1.
2 .
3
4 .
t h e u r f a c ec o n d i t i o n s .
REFERENCES
H . Nilsson,SubPower A B : "Deepdater Air-
I n d e p e n d e n tP o w e rS o u r c e sb a s e do nS t i r l i n g
Engines"
-
UncerwaterTechnologyConfereRce,
S e r gen ,Kor way ,Apr i l 984 .
Y. Curand, Comex Ind us tr ie s , nd H . N i l s s o n ,
Sub ?ower A B : "HighDensi tyUnderwaterEnergy
S c c r c e s . .4 3 a d i c a lT r a n s f o r m a t i o nc fS u b s e a
Oper a t ions" The E . E . Z . Sympcslom i n Lcxem-
bourg, ecernber 984.
P .A. tenberg,Kockuns A S : " S t i r l i n g ?ower
Systems f o r S ubm ar ines" Mar i t ineD e f e r c e ,
J anuar y1985 .
H .
Nilsson,SubPower A B : "S ur f ace ndependent
Ener gyS u p p l y oD e e ph ' a te rOper z t ions"
TheOf f shor eConf e r ence nCothenbur g ,
TebruPrv
1 9 8 5 .
r-
: E l
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Regenerator.
t(
Cooler
Figure
1.
The doub le act ing St i r l ing working pr inciple
FUEL
OXYGEN
OXYGEN NOZZLE
FUEL INJECTOR
PRESSURIZED
COMBUSTION CHA MBER
EXHAUST
COOLING WATER
CYLINDER BLOCK
DRIVE SHAFT
CRANKCASE
DRY
SUMP
=:Sure
2. 4 95
Sub cross sect ion
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\ EXHAUST
p4
1
750°C
\
\
3
The CGR basic pr incip le
jector
tubes
.
-
5. The 4-275 underwater engine
Figure 4. A Sti r l ing powered submersib le
Figure
6.
The 4-275 underwater engine
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WEIGHT COMPENSATION TANK
:
Figure
7
The St ir l ing sys tem te st plant
.
Figure 8. The St ir l ing system test plant
SUPPLY
GOX t
Q G - w V -
EVAPORATOR
t
SUPPLY LINE LOX
I
i
CONTROL
CTROy LlN,ES ,:
,T
PRESSURE
RISING
L
I
' iit
LINE
LEVEL INDICATING
Figure 9 LOX system for the St ir l ing test plant
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1
Ton Attack Submarine
Hybrid Diesel Stirl ing Machin ery
Liquid Oxygen Tank7 Stirling generator
Diesel generator [Storage Battery
Figure 10 A naval subm arine wi th an integrated St i r ling sect ion
EATERY DISCHARGE
(TARGET ENGAGEMENT)
STIRLING RUNNING
Figure 11. Fict ional ope rat ional prof ile for a St i r ling powe red subm arine
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b
Hatch For A tmos pher ic Compar tment
I
Rescue Bel l
Hydrau l i c Thrus ter
\
/
\
LDiesel Engineiver Transfer Lock
St i r l ing Engine
I
Engine Room
/
I
Observat ion Post
Mess Room
Figure
12
S A G A
I
submarine inter ior arrangement
t
Figure
13 SAG A
I Engine Room and Control Room
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OxygenlHel ium OxygenlHel ium
ARG.DP. 12.04.104
Figure
14.
The SAG A I submarine Oxygen storage arrangement
THE
SAGA SUBMARINE DESIGN MISSION
Design case:
Diving operations at Coromant field
Submarine base: Stavanger
Transit distance: 150 naut. miles (submerged)
Mission profile:
Transit:
2 x 40
hrs
Diving support:
200
hrs
Total submerged mission: 10 days
Figure 15. Miss ion A . Diving support
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THE SAGA SUBMARINE DESIGN MISSION
Design case:
PipelinelBottom survey in the Sicilion Straits
Submarine base: Palermo
Transit distance: 100 naut. miles (submerged)
Mission profile:
Transit
2 x
25 hrs
Surveying:
200
hrs (1 knot)
Total submerged mission: 10 days
Figure
16
Mission B. Surveying
TOTAL
WEIGHT:
300
K g
Figure
17 A pod
instal lat ion
of
the
V 160
engine
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I
Figure
18
The vehic leldiver s heat ing system
Figure
19
A
habi tat pro jec t Kockums)
r
t i r l ing generator
I
g en er at o r L i q u i d Oxyg enank \Storage Battery
Figure 20 A naval submar ine wi th a hybr id machinery
(Diesel & St i r l ing)