1
Fuel-Sa ing Po en ial o Di e en Bulk Ca ie s using Ai Lub ica ion
Sys ems
Shibo Zhao 1,* Kay an Pazouki 1 and Rosema y No man 1
1 Newcas le Uni e si y, Newcas le upon Tyne, UK
Abs ac . Due o he impac o global wa ming, he e is an inc easing mo i a ion o imp o e he ene gy
e iciency o p opulsion sys ems o use new echnologies o educe ship ene gy consump ion. Ai lub ica ion
sys ems (ALS) ha e been p oposed as a p omising ene gy-sa ing echnology ha can e ec i ely educe uel
consump ion and g eenhouse gas emissions o ships. Howe e , he cu en e alua ion indica o s o ALS o
educe ship ene gy consump ion mainly use powe sa ing a e o d ag educ ion a e, which canno in ui i ely
e lec he uel sa ing e ec o he en i e ship. A he same ime, he uel sa ing e ec o ALS on di e en ship
ypes may also be di e en . This pape employs he Hol op me hod o es ima e ship esis ance and ex ends he
d ag educ ion a e ob ained om expe imen al calcula ions o ull-scale wi h he applica ion o an ai
lub ica ion sys em. The main engine ou pu powe is de e mined based on he o ce equilib ium p inciple in
s eady sailing, while also conside ing a ia ions in diesel gene a o load om he ai lub ica ion sys em. A
eg ession analysis is conduc ed o es ablish he ela ionship be ween uel consump ion and he load on bo h
he main engine and diesel gene a o s. Fu he mo e, a g ay-box ship uel consump ion model inco po a ing ai
lub ica ion echnology is de eloped using MATLAB/Simulink o simula ion. By applying ai lub ica ion
echnology o six di e en ypes o bulk ca ie - Small, Handysize, Handymax, Panamax, Capesize and VLBC
- he uel sa ing e ec s o di e en ship ypes when using ALS a e compa ed. The esul s show ha VLBC
bulk ca ie s achie e he highes uel sa ings a highe speeds, while smalle ship ypes exhibi mo e signi ican
d ag educ ion e ec s. No ably, small bulk ca ie s can achie e a uel sa ing a e o up o 16.3% a a speed o
14 kno s.
Keywo ds: Ai Lub ica ion Sys em, Modelling, Simula ion, Bulk ca ie s.
1 In oduc ion
Due o he impac s o global wa ming and ai pollu ion, a ious egula ions and s anda ds o limi he emission
o g eenhouse gases and ai -quali y pollu an s ha e been o mula ed and implemen ed [1]. As es ic ions on
ca bon emissions om ships become inc easingly s ingen , he shipping indus y is ac i ely adop ing new
echnologies o comply wi h he egula o y equi emen s [2]. The ai lub ica ion sys em (ALS) is an ene gy sa ing
de ice ha educes he ic ional esis ance o he hull by o ming a laye o mic obubbles a he bo om o he
hull, he eby educing he powe demand o he main engine (ME) and uel consump ion [3].
ALS demons a es mul iple compa a i e ad an ages o e o he ene gy sa ing de ices. Fi s , i s ope a ional
pe o mance is only minimally a ec ed by en i onmen al condi ions, which gi es i b oade applicabili y
compa ed o clima e-dependen echnologies such as wind-assis ed p opulsion. Second, he sys em equi es he
ins alla ion o ai injec ion de ices only along he bo om o he hull. This a angemen does no in e e e wi h
deck ope a ions o educe ca go hold capaci y, hus minimising nega i e impac s on he essel’s ope a ional
e iciency. Thi d, he o e all sys em weigh is ela i ely low. In con as o la ge-scale ene gy-sa ing equipmen
such as sails o was e hea eco e y sys ems, ALS imposes limi ed addi ional weigh on he essel. This helps
a oid inc eased uel consump ion ha may esul om highe deadweigh . In addi ion o educing g eenhouse gas
emissions, hull ai lub ica ion can also help mi iga e unde wa e noise by minimizing ib a ions, engine noise, and
he accumula ion o ma ine o ganisms [4]. Due o hese echnical ad an ages, ALS has a ac ed mo e and mo e
a en ion om he shipping indus y and esea che s.
Kodama e al. conduc ed expe imen s using model ships, con i ming ha bubbles educed bo h he o al
esis ance ac ing on he model and he local ic ion ac ing on he ship's bo om [5]. Pa k e al. conduc ed an
expe imen on an oil anke model, achie ing a d ag educ ion o 18.1% by selec ing he op imal ai injec ion
* Co espondence o: [email p o ec ed]
16 h In e na ional Symposium on P ac ical Design o Ships and O he Floa ing S uc u es PRADS 2025
Ann A bo , MI, USA, Oc obe 19 h – 23 d 2025
2
con igu a ion and he dis ibu ion a io be ween wo injec o s [6]. Kim e al. buil an ALS ene gy-sa ing model,
which showed a po en ial ne powe sa ings a e o 3-24% o he global lee [7].
Al hough esea ch on ai lub ica ion sys em has been ela i ely ex ensi e, cu en s udies p ima ily use
indica o s o he po en ial o an ALS o educe ship ene gy consump ion mainly use powe sa ing a e o d ag
educ ion a e. Howe e , hese me ics do no in ui i ely e lec he uel sa ing e ec o he whole ship. A he
same ime, he uel sa ing e ec o an ALS may also a y o di e en ship ypes. The e o e, o gain a mo e
comp ehensi e unde s anding o he applica ion p ospec s o ALS, his s udy compa es and analyses he uel
sa ing e ec o a ious ypes o bulk ca ie . This will allow shipping companies o be e e alua e he applica ion
alue o ai lub ica ion sys ems o di e en bulk ca ie s, he eby e ec i ely educing uel consump ion and
imp o ing he economic bene i s o o e all ope a ions.
The es o his pape is o ganised as ollows: The ma e ials and modelling me hod will be in oduced in Sec ion
2. The simula ion esul s o uel sa ing using ai lub ica ion sys ems on di e en ships a e analysed in Sec ion 3.
Sec ion 4 p esen s he conclusions, summa ising he uel sa ing po en ial o using ALS on six di e en bulk
ca ie s.
2 Ma e ials and me hods
2.1 Ship Speci ica ions
Six di e en ypes o bulk ca ie a e used as e e ence ships in his s udy - Small, Handysize, Handymax,
Panamax, Capesize and VLBC. The dimensions, size and ME Maximum Con inuous Ra ing (MCR) Powe
pa ame e s o he e e ence ships a e shown in Table 1.
Table 1. Main pa ame e s o he a ge ship
Classes
Dimensions (L×B×D, m)
Size (DWT)
ME MCR Powe (kW)
Small
115×15.26 ×11.5
14500
1×5500
Handysize
170×26.3 ×10
33500
1×8250
Handymax
190×32.26 ×11.5
53000
1×10500
Panamax
225×32.3 ×13.1
71000
1×11500
Capesize
285×45 ×18
172000
1×18000
VLBC
300×50 ×18.73
205000
1×20900
The elec ical powe equi emen s o di e en ypes o bulk ca ie using ai lub ica ion sys ems, Pg, can be
calcula ed using Eq. (1).
𝑃
𝑔
=
𝑃
𝑆
+
𝑃
A,L
(1)
whe e PA,L is he elec ical powe equi emen o he ai je pump when using ai lub ica ion echnology and PS
is he powe equi emen o he bulk ca ie when sailing a sea, as shown in Table 2 [8].
Table 2. Bulk ca ie powe equi emen s
Vessel
Powe demand (kW)
Type
Size (dw )
Be h
Ancho
Man.
Sea
0-9999
110
180
500
190
10000-34999
110
180
500
190
35000-59999
150
250
680
260
60000-99999
240
400
1100
410
100000-199999
240
400
1100
410
Bulk ca ie
200000-+
240
400
1100
410
3
2.2 Ship Resis ance
In his pape , he esis ance mainly conside s he hyd os a ic esis ance. The hyd os a ic esis ance e e s o
he esis ance gene a ed by he wa e on he hull when he ship is sailing in calm wa e . Acco ding o he Hol op
esis ance es ima ion me hod, he ship's calm wa e esis ance can be exp essed as Eq. (2) [9].
𝑅
𝑡
=
𝑅
𝑓
(1
+
𝑘
1
)
+
𝑅
app
+
𝑅
𝑤
+
𝑅
𝑏
+
𝑅
+
𝑅
𝑎
(2)
whe e R is he o al hyd os a ic esis ance, R is he ic ional esis ance, k1 he iscous esis ance ac o om
di e en ship ypes, Rapp is he appendage esis ance, Rw is he wa e-making esis ance, Rb is he bulbus bow
esis ance, R is he ansom esis ance and Ra is he model co ela ion esis ance.
(1) F ic ional esis ance
F ic ional esis ance is he esis ance due o he ic ion o he wa e low agains he su ace o he hull. This
pa o esis ance usually accoun s o a la ge p opo ion o he o al esis ance. The ic ional esis ance can be
exp essed as Eq. (3) [9].
𝑅
𝑓
=
1
2
𝐶
𝑓
𝜌𝑆
𝑉
2
𝑠
(3)
whe e C is he coe icien o ic ional esis ance, ρ is he densi y o seawa e , S is he we ed a ea, and Vs is
he ship speed h ough wa e .
Acco ding o he calcula ion guidelines ecommended by ITTC in 1957 [9], C can be calcula ed by he Eq.
(4).
𝐶
𝑓
=
0.075
(
𝑙𝑜𝑔
10
𝑅
𝑒
―
2
)
2
(4)
whe e Re is he Reynolds numbe , which can be ob ained by Eq. (5).
𝑅
𝑒
=
𝑉
𝑠
𝐿
wl
𝜈
(5)
whe e is he dynamic iscosi y o wa e and Lwl is wa e line leng h.
(2) Appendage esis ance
Appendage esis ance e e s o he esis ance o d ag caused by he p esence o he pa s o appendages o a
ship ha ex end in o he wa e , such as he bilge keels, udde , p opelle , o any o he p o uding pa s. The o mula
used he e o calcula ing he appendage esis ance is gi en by Eq. (6) [9].
𝑅
app
=
0.5𝜌
𝑉
𝑠
2
𝑆
app
(1
+
𝑘
2
)
eq
𝐶
𝑓
(6)
whe e Sapp is we ed su ace a ea o a ship's appendages, 1+k2 is he shape ac o o ship appendages.
(3) Wa e-making esis ance
Wa e-making esis ance is he esis ance p oduced by wa es gene a ed when a ship mo es in wa e . I is he
mos impo an componen o esis ance a highe speeds, and wa e esis ance is p opo ional o he squa e o he
ship's speed and he amoun o wa e displaced by he hull. The o mula used he e o calcula ing Rw is [9]:
𝑅
𝑤
=
𝐶
1
𝐶
2
𝐶
5
𝛥𝜌
𝑒
{
𝑚
1
𝐹
𝑟
―
0.9
+
𝑚
2
𝑐𝑜𝑠
(
𝜆𝐹
𝑟
―
2
)
}
(7)
whe e
𝛥
is he displacemen olume o a ship, in m3, C1, C2, C5, m1, m2 and λ a e all coe icien s, which a e
de e mined by ele an calcula ion o mulas.
The o mula o he F oude numbe F is as shown in Eq. (8)
𝐹𝑟
=
𝑉
𝑠
𝑔
𝐿
wl
(8)
4
whe e g is he g a i a ional accele a ion, aken as 9.8 m/s2.
(4) Bulbus bow esis ance
Bulbous bow esis ance is a e m used in ship hyd odynamics o desc ibe he addi ional esis ance o d ag
c ea ed by he bulbous bow on he on o a ship. The bulbous bow is a p o usion o bulb-like shape ha ex ends
om he hull o he ship below he wa e line. I can be calcula ed by he ollowing Eq. (9) [9].
𝑅
𝑏
=
0.11
𝑒
(
―
3
𝑃
ℎ
―
2
)
𝐹
𝑟
3
𝑖
𝐴
1.5
BT
𝜌𝑔
(1
+
𝐹
𝑟
2
𝑖
)
(9)
whe e Ph is ela ed o he wa e imme sion dep h o he bow, F i is he F oude numbe based on he wa e
imme sion, ABT is he ans e se sec ional a ea o he ship.
Since he bulbous bow esis ance accoun s o a small amoun o he o al hyd os a ic esis ance, usually less
han one en- housand h, he bulbous bow esis ance is no conside ed in he modelling in his pape .
(5) T ansom esis ance
Ship ansom esis ance e e s o he esis ance o d ag c ea ed by he la o sligh ly cu ed s e n o a ship,
which is known as he ansom. R can be calcula ed by he ollowing Eq. (10) [9].
𝑅
=
0.5𝜌
𝑉
𝑠
2
𝐴
𝑇
𝐶
6
(10)
whe e AT is he midship sec ional a ea o he imme sed s e n, AT=0.051AM=0.051BdCM, CM is he midship
sec ion coe icien , C6 is ela ed o he F oude numbe o he imme sed s e n, when F d＜5, C6=0.2(1-0.2F d), when
F d≥5, C6=0. F d is he F oude numbe o imme sion.
(6) model co ela ion esis ance
Ship model co ela ion esis ance e e s o he p ocess o compa ing he measu ed esis ance o a ship model
in a owing ank o he p edic ed esis ance o a ull-scale ship. The aim o his p ocess is o alida e he accu acy
o he ship model and he eliabili y o he me hods used o p edic he pe o mance o he ull-scale ship. The
o mula o Ra is [9]:
𝑅
𝑎
=
0.5𝜌
𝑉
𝑠
2
𝑆
𝐶
𝐴
(11)
whe e CA is he co ela ion allowance coe icien .
2.3 Ai lub ica ion Sys em
An ALS uses gas injec o s ins alled a he bo om o he ship o elease comp essed ai , o ming a laye o
mic o-bubbles as a blanke unde he hull, he eby lowe ing ic ional esis ance. I s main p inciple is o educe
ic ional esis ance by educing di ec con ac a ea wi h he wa e , ha is, by eleasing bubbles and co e ing pa
o he bo om su ace o he hull o educe he we ed su ace a ea. Due o he complexi y o bubble low, his
pape calcula es he d ag educ ion a e by combining he d ag educ ion e ec s unde di e en ai low a es (Fig.
1) by Zhao e al. [10]. Based on h ee di e en d ag educ ion zones—mic obubble d ag educ ion, ai lub ica ion
laye , and he zone be ween hem— he d ag educ ion a es a e in e pola ed o di e en F oude numbe s and ai
injec ion a es. This app oach in eg a es heo y wi h da a o model he ai injec ion d ag educ ion echnology using
a g ay-box model.
5
Figu e 1. The d ag educ ion e iciency in he expe imen s a di e en ai low a es (adap ed om [10])
As can be seen om Fig. 1, o be e ensu e he luid dynamics simila i y be ween he expe imen and he ull-
scale ship, and o make he analysis o d ag educ ion e iciency a di e en ai low a es mo e scien i ic and
scalable, di e en F oude numbe s a e gi en in he igu e o analyse he d ag educ ion e iciency unde di e en
ai low a es. When he F oude numbe is he same, he ull-scale ship speed can be calcula ed om he model
ship speed using Eq. (8).
The d ag educ ion a e ηR using ALS is de ined as Eq (12).
𝜂
𝑅
=
𝑅
0
―
𝑅
𝑅
0
×
100%
(12)
The equi ed powe o ai injec ion is es ima ed as he powe equi ed o comp ess a gi en amoun o ai
h ough a mul idi ec ional p ocess a s anda d a mosphe ic p essu e [3].
𝑃
con
=
𝑚
𝐴𝑖𝑟
𝜂
𝑐
𝜌
𝑔,𝑎
⋅
𝑝
1
⋅
𝑛
(𝑛
―
1)
(
[
𝑝
2
𝑝
1
]
(𝑛
―
1)/𝑛
―
1
)
(13)
whe e mAi is he mass low a e o he injec ed ai , he mul iple index n is eplaced by he ai speci ic hea
a io k=1.40, ρg,a is he ini ial densi y o he comp essed ai , ηc is he comp esso e iciency, p1 is he ini ial p essu e,
assumed o be 1a m, p2 is he p essu e he gas needs o be comp essed o, which can be calcula ed by using Eq.
(14) [3].
𝑝
2
=
𝑝
1
+
𝜌
𝑠
⋅
𝑔
⋅
𝑇
+
𝛥𝑝
(14)
whe e ρS is he densi y o seawa e .
Since he ai injec ion a e in Fig. 1 is based on an expe imen al ship model, i needs o be con e ed in o he
ai injec ion a e o he ac ual size ship, which can be ob ained h ough Eqs. (15) and (16) [3].
𝑡
AL
=
𝑄
Ai
𝑉
In low
⋅
𝐵
Ai
(15)
𝑡
AL
=
𝑄
Ai
𝑉
𝑠
⋅
𝐵
Uni
(16)
whe e QAi is he olume low a e o injec ed ai , and BUni is he wid h o he injec ed ai uni .
0 2 4 6 8 10
Q (m3/h)
-10
-5
0
5
10
15
20
η(%)
F =0.08
F =0.10
F =0.12
F =0.16
F =0.20
6
2.4 Ship uel Consump ion
Fo ships equipped wi h ALS, a laye o mic obubbles is o med unde he hull o educe he esis ance
encoun e ed du ing sailing, he eby educing he p opulsion powe equi ed om he main engine. When he ship
is sailing a a s eady speed, he p opelle h us balances he hull esis ance, and his ela ionship can be desc ibed
by Eqs. (17) and (18).
𝑅
𝐴
=
𝑅
𝑡
⋅
(100%
―
𝜂
𝑅
)
=
𝑇
𝐸
(17)
𝑃
𝐸
=
𝑇
𝐸
⋅
𝑉
𝑆
=
𝑅
⋅
(100%
―
𝜂
𝑅
)
⋅
𝑉
𝑆
(18)
whe e RA is he o al esis ance using ALS, TE is he e ec i e h us o he p opelle and PE is he e ec i e
powe o p opelle .
Due o losses associa ed wi h he p opelle , he powe deli e ed o he p opelle PD mus be g ea e han he
e ec i e powe o p opelle PE. The a io o he e ec i e powe o he deli e ed powe is called he quasi
p opulsi e coe icien ηD, which is usually be ween 0.55 and 0.65 [11]. The e o e, he powe ans e ela ionships
a e illus a ed by Eqs. (19) and (20).
𝑃
𝐷
=
𝑃
𝐸
/
𝜂
𝐷
(19)
𝑃
𝐵
=
𝑃
𝐷
/(
𝜂
𝐺
⋅
𝜂
𝑆
)
(20)
whe e PB is he main engine powe ou pu , ηG is he gea box e iciency, ηS is he sha ansmission e iciency.
Acco ding o he esea ch by Deng e al., he p opulsion e iciency loss using he ai lub ica ion sys em is less
han 1%, indica ing ha he impac o bubbles on he p opelle may be minimal [12]. Based on his inding, and in
he in e es o model simplici y, his s udy neglec s he a ia ion in p opulsion e iciency caused by bubbles.
The uel oil consump ion o he main engine can be de e mined using Speci ic Fuel Oil Consump ion (SFOC)
o he main engine and Eqs. (21) and (22).
𝑞
𝑚
=
𝑃
𝐵
⋅
𝑔
𝑚
(21)
𝐹
𝐶
𝑚
=
𝑞
m
×
𝑡
(22)
whe e
q
m is he hou ly uel consump ion o he ship,
g
m is he SFOC o he main engine, FCm is he o al uel
consump ion o he ME, is he un ime o he engine (in hou s).
The uel consump ion o he diesel gene a o (D/G) can be de e mined using he quad a ic eg ession
polynomial o he uel consump ion o he diesel gene a o se a di e en loads and Eq. (23).
𝐹
𝐶
𝑔
=
𝑛
∑
𝑖
=
1
𝑞
g,
i
(
𝑃
𝑔
)
×
𝑡
i
(14)
whe e FCg is he o al uel consump ion o he D/Gs, qg is he consump ion a e (kg/h), i is he numbe o D/Gs
in ope a ion.
O e all, he o al ene gy consump ion o he ship is gi en by he sum o he ME uel consump ion and he uel
consump ion o he D/Gs, as shown in Eq. (24).
𝐹𝐶
=
𝐹
𝐶
𝑚
+
𝐹
𝐶
𝑔
(14)
whe e FC is he o al uel consump ion o he ship.
2.5 Powe dis ibu ion s a egy
The elec ical dis ibu ion sys em model using he ALS is shown in Fig. 2.
7
Figu e 2. Powe dis ibu ion sys em model using ALS
I can be seen om he igu e ha h ee D/Gs a e used o powe he ALS and o he elec ical loads on he ship.
Due o he small di e ence in uel consump ion o D/Gs wi h di e en ins alled powe s when using ai lub ica ion
echnology, i is assumed ha all six ypes o bulk ca ie s a e equipped wi h h ee 500kW D/Gs, and he D/G uel
consump ion using ALS is calcula ed. In he s udy by Yiği e al. [13], quad a ic eg ession polynomials we e used
o uel consump ion unde di e en loads o 500 kW D/Gs. Thei indings showed ha ope a ing he gene a o a
90% capaci y, ins ead o 40%, esul s in lowe uel consump ion and educed uel cos s. Based on his, he load-
sha ing limi o he gene a o is se o 90% [13]. The load sha ing p ac ice be ween h ee di e en gene a o s can
be seen in Fig. 3.
Figu e 3. Load sha ing p ac ice be ween gene a o s
3 Resul s and discussion
A ship uel consump ion model o he ship equipped wi h ALS was de eloped, and he elec ical load a e
adop ing ALS was alloca ed acco ding o he de eloped diesel gene a o powe alloca ion s a egy.
To compa e he impac o di e en speeds on he uel e iciency o he ship equipped wi h ALS, he uel
consump ion and uel sa ings a es o di e en ypes o bulk ca ie s we e calcula ed a di e en ship speeds wi h
an ai injec ion a e o 10 m3/h, as shown in Fig. 4 and Table 3.
8
(A) Small (B) Handysize (C) Handymax
(D) Panamax (E) Capesize (F) VLBC
Figu e 4. Compa ison o uel consump ion and uel sa ing o di e en ship ypes and di e en speeds
Table 3. Main pa ame e s o he a ge ship
Classes
Fuel sa ing amoun (kg/h)
Fuel sa ing a e (%)
Small
128.1
15.9
Handysize
144.2
13.8
Handymax
181.9
13.3
Panamax
190.7
12.3
Capesize
309.0
10.6
VLBC
335.5
10.1
As can be seen om Fig. 4, as he speed inc eases, he uel sa ing e iciency o he six ypes o bulk ca ie s
ises. This is because as he ship speed inc eases, he bubbles o med by he ai injec ion a e mo e easily e enly
dis ibu ed on he bo om o he ship, o ming a s able and con inuous bubble laye . This no only e ec i ely
educes he ic ional esis ance be ween he hull and he wa e bu also signi ican ly enhances he d ag educ ion
pe o mance o he ai lub ica ion sys em, leading o g ea e uel sa ings. A a maximum design speed o 14 kno s,
he uel sa ing a e a ies om 10.1% o he VLBC o 15.9% o he Small sized bulk ca ie when using ALS.
The VLBC has he highes hou ly uel consump ion so, al hough i has he lowes uel sa ing a e a he selec ed
speed, i s ill sa es he mos uel.
To compa e he impac o di e en ai injec ion a es on he uel e iciency o he ship equipped wi h ALS,
he uel consump ion and uel sa ings a es o di e en ypes o bulk ca ie s we e calcula ed a di e en ai
injec ion a es wi h a ship speed o 14 kn, as shown in Fig. 5.
As can be seen om Fig. 5, a ying he ai injec ion a e om 6 o 10m3/h has li le e ec on he uel
consump ion o each ship ype, as his ange alls wi hin he ai lub ica ion laye zone. A his s age, a con inuous
and s able bubble laye has al eady o med benea h he hull, e ec i ely minimising hull–wa e con ac . Fu he
inc eases in ai injec ion do no signi ican ly educe he con ac a ea, esul ing in a sa u a ed d ag educ ion e ec
and a uel sa ing a e ha no longe imp o es app eciably. Addi ionally, Handysize, Handymax, Panamax,
Capesize, and VLBC bulk ca ie s ha e he bes uel sa ing e ec when he ai injec ion a e is 10 m3/h. Con inuing
o inc ease he ai injec ion a e has limi ed impac on uel sa ing bu will inc ease he D/G load and uel
consump ion, esul ing in an inc ease in o al uel consump ion. Howe e , he Small bulk ca ie eached i s
op imal d ag educ ion a e wi h an ai injec ion a e o 6 m3/h.
0
5
10
15
20
Fuel Sa ing Ra e (%)
10 11 12 13 14
Ship Speed (kn)
200
300
400
500
600
700
Fuel Consump ion (kg)
Fuel Consump ion
Fuel Sa ing Ra e
0
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Fuel Sa ing Ra e (%)
10 11 12 13 14
Ship Speed (kn)
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400
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Fuel Sa ing Ra e
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Fuel Sa ing Ra e (%)
10 11 12 13 14
Ship Speed (kn)
200
400
600
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Fuel Consump ion (kg)
Fuel Consump ion
Fuel Sa ing Ra e
0
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Fuel Sa ing Ra e (%)
10 11 12 13 14
Ship Speed (kn)
200
400
600
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1400
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Fuel Consump ion
Fuel Sa ing Ra e
0
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10 11 12 13 14
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0
500
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Fuel Consump ion (kg)
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Fuel Sa ing Ra e
0
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Ship Speed (kn)
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Fuel Consump ion
Fuel Sa ing Ra e
9
(A) Small (B) Handysize (C) Handymax
(D) Panamax (E) Capesize (F) VLBC
Figu e 5. Compa ison o uel consump ion and uel sa ing o di e en ship ypes and di e en ai injec ion a e
4 Conclusion
The uel consump ion models o six di e en ypes o bulk ca ie , including small, Handysize, Handymax,
Panamax, Capesize ca ie s and VLBC, when using ALS we e de eloped. The simula ion esul s show ha a
highe speed may achie e a mo e signi ican d ag educ ion e ec . The highes uel sa ing a e is o small bulk
ca ie s a 14 kn, wi h a uel sa ing a e o up o 16.3%. The maximum uel sa ing capaci y is o he VLBC a 14
kn, which is 335.5kg/h. In he ai laye d ag educ ion a ea o he ship, when he d ag educ ion a e inc eases o a
ce ain ex en , con inuing o inc ease he ai injec ion a e has li le posi i e e ec on uel sa ing, and may lead o
an inc ease in o al uel consump ion due o he inc ease in D/G uel consump ion.
The u u e esea ch should ocus on op imising he ai injec ion a e o di e en ship ypes and ope a ing
condi ions o achie e a balance be ween d ag educ ion and o al uel consump ion. Addi ionally, i is also
ecommended o explo e he long- e m ope a ional pe o mance and economic easibili y o ALS unde a ied sea
s a es and oyage p o iles.
Acknowledgmen s
Au ho SZ was suppo ed by g an 202206950022 om he China Schola ship Council.
Re e ences
[1] L.P. Pe e a and B. Mo. Emission con ol based ene gy e iciency measu es in ship ope a ions. Applied Ocean Resea ch,
60: 29-46, 2016.
[2] V.J. Jimenez, H. Kim and Z.H. Munim. A e iew o ship ene gy e iciency esea ch and di ec ions owa ds emission
educ ion in he ma i ime indus y. Jou nal o Cleane P oduc ion, 366: 132888, 2022.
[3] J. Jang, S.H. Choi, S.M. Ahn, B. Kim and J.S. Seo. Expe imen al in es iga ion o ic ional esis ance educ ion wi h ai
laye on he hull bo om o a ship. In e na ional Jou nal o Na al A chi ec u e and Ocean Enginee ing, 6(2): 363-379,
2014.
[4] Sa e y4Sea. Ai Lub ica ion: How Blowing Bubbles unde Ships Can Reduce Emissions, G eece, 2023.
h ps://sa e y4sea.com/cm-how-blowing-bubbles-unde -ships-can- educe-
emissions/?u m_medium=DNV%20-%20Ma i ime&u m_campaign=MARANDE%2CBA-
Ma i ime&u m_sou ce=linkedin&u m_con en =90d3105014b744b7b4 de5c867252628-
5011444&u m_ e m=social& bclid=IwAR1DLxJyO2IinhsRqoTAPc h_OmC KLWmRWnxhCAhYOK-
61TQuKkVg2hzPQ [accessed 24 July 2025].
0
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