CA1184441A - Ice-ship - Google Patents

Abstract

ICE-SHIP
Abstract of the Disclosure Disclosed is an ice-ship comprising a hull, trimming tanks and heeling tanks, an anti-icing system incorporating a compressor with a drive, at least two air manifolds with openings used to blow out the air, arranged below the water-line symmetrically with respect to the fore-and-aft line along the hull and connected with the compressor by means of an air supply pipeline. The air manifolds of the anti-icing system are fastened to the external surface of the ship hull in the bildge portion thereof, while said openings used to blow out the air are made in the lower portion of the air manifold. Furthermore, the anti-icing system is pro-vided with two additional air manifolds arranged along a stempost of the ship, fastened to the hull symmetrically with respect to the stempost in the immediate vicinity thereto, connected with the air supply pipeline and hav-ing openings to blow out the air, the diameters of said openings increasing as they approach the bottom of the hull, and at least one air heater installed in the air supply pipeline.
Figs. 1, 2.

Description

~iel~ of the I~vention The pxesent inYe~tion relates to the water transport9 and more particularly, to ice-ships.
-Lost advantageously~ the present invention can be used for nuclear-powered ice-breakers. I
~ackgroun~ of the InvPrltio~
~ 'he sailing of ships in the seas oY the Arctic Ocean is complicated by ice which covers the seas practically -the yaar round.
'~he snow-co~ered and fresh ice f'reguently freezes to ship hulls, icreasin~ -the ship resistance to motionc '~his phenomenon acoompanies up to 25 per cent of the spip travel time in ice r~gions 9 reducing the ship speed and, hence 7 the efficiency oi` operation ol` ships on average, by 50 to 55 per cen-t.
~ he ~rosti~g-up of' hulls of the ships shoul~ be avoid-ed in order to il~prov0 their propulsive guality in ice.
~ nown in the prior art is a variety o~` ~ethods allo~-i~g the f'rosting~u~ of ships to be reduced~ ~'hey include heating of' the ship hull, hydraulic and pneumatic washi~g the ship hull.
In order to decrease t~e ship ~'rosting~up by heating the hull in the region o~ its contac-t v~i-th the ~rosen ice 9 the heat OI` a heated working medium is supplied to said region to mel-t the ice layer in the region o~ its contact with the ship hull a~d to produce a water layer between the ship hu11 an~ the ice, thus preventing the ship ~rosting-up.

As the ship is advancing, said water layer is con-ti-nuousl~ decreased by the overtakin~ water floYl, by variat-ion in ice pressuIe on the ship hull~ etc .
To produce ~he required ~ater layer in the region of contact between the ship hull and the ice and, hence, to reduce the ship ~rosting-up high energy expe~ditures are reguired.
~ hen the hydraulic uashing of the ship is used, water is exhausted u~der pressure through openings in the ship hull below the waterlineO ~his water moves to the surface water layer, entrains the ~earest layers of the sea ~la-ter and, thus, produces a fl~7 along the ship hull, prevent-in~ the ice freezing thereto. Howe~er, the speed of ~l~v of the water fed under pressure decreases as it moves away *rom the openin~s. ri'his reduces ~he ~hickness of layer of the sea water being lifted and, hence, decr~ases the effi-ciency of the hydraulic washin~ ~ the ship hull.
Therefol-e, in order to provide a high speed of the water flow it should be supplied at a high pressure. This determines the substalltial ener~y expenditures re~uired to produce the hydraulic flo~ and, in turn, requires pumps o~ high capaci-ty and, hence~ of large size an~ weight.
To produce the pneu~tic flow, air is blown out through openin~s in the ship hull, arranged below the wa-terline, the bubbles li~tin~ -the sea water; the la-tter wets in-tensively the contact region between the ship hull and the ice~ melts the ice and, -thus, reduces the freez~

~4~

ing of the ice to the ship hull. This decIeases, in turn, the ship hull Irosting-up.
hir bubbles are lifted to the surface ~later layer b~
the buoyncy forces at a constant velocity which does not reguire a high pressure to be r,laintained. As a result sub-stantial energy expenditures are not reguired to provide an effective pneumatic flow along the ship.
~ L~Us~ at present the most promisin~ anti icing sys-tems are pneumatic ones.
In ice~ships~ -the anti-icin~ systems shoul~ provide:
- maximum flow along the ship hull in -the bovJ and middle por~ions thereof where the ship ~rosting-up pro-cess starts ~irst;
- maximum thickness of -the layer OI` sea ~ater washing the ship hull an~ lifted b~ the air;
- minimum energy e~penditures to produce an ef~ec-ti~e pneumatic ~low;
- reliability in service ~ nown in the prior art is an ice-ship comprisin~ a hull with an anti-icing system incorporatin~ two ~ani-~olds having openings used to blow out a steam air mix-ture. ~ach ol` the mani-~olds is -formed by a shaped member and a portion of the i~ternal surface OI' the hu115 to which it is fastened, a is arrar~ged below the waterline alon~ t~e ship hull~ Both m~nifolds are arranged sy~e$rical-ly with respect to the fore-anà-a~$ line o~ the snip. The mani~old ope~ings used to blow out the steam-air mixture are made in the ship hull. The anti~ici~æ system also comprises ~wo jet-type compressors uith pipelines to supply the steam~air mixture to t~e manifolds, coupled to the steam-generating piant of the ship through shu-t~-off valves (US~R Au-thorls Certificate ~o.382544, published in 1973)o In the ice-ship mentioned hereinabove, the pneumatic v~ashing of the hull is accomplishe~ by the steam-air mix-ture whose steam bubbles condense as they are accendi~g to the -iJater sur~ace. ~his does not allo~ a layer o~ flo~-ing YJater of a su~ficient thickness -to be produced an~, hence, reduces the efficienc~ of the pne~matic flow and -the propulsive guality o~ the ~hip in ice.
To produce the steam-air mi~ture, the steam is taken from the ship s-team-generating plant. High energy expendi-tures aIe reguired to make up Ior the steam lost in said plant,which reduces its capacity.
~ he je-t-type compressors installed in the ship con-SUlQp substantial energy to provide the necessary pressure of the stea~-air mixture. This also reduces the capacity o~
the ship st~am-generating plan-t.
FurtherlQore, the steam-air mi~ture is an aggresive medium bringin~ about corrosion ~ the pipelines and ma-ni~olds, reducing their reliability.
In the ice-ship discussed hereinabove, the an~i-icing system doe~ not provide direct pneumatic washing of the extremity o~ the ship since, thougk the openin~s th~sugh which the steam-air mix*ure is blown ou-t, are also arranged in the bow portion of the ship, nevertheless a ~oticeable drift o~ the ascending air bubbles towardæ
the stern takes place during the ship advancement. This also r~duces the efXiciency of the pneumatic washing of the ship hull and 9 hence, the propul~ive guality oX the ship in ice.
'i'he disadvall-ta~es discussed hereinabo~e are partially ,eli~iinated in an ice-ship which is taken as a prototype to the presen,t,invention. '~his ship comprises a hull, tri~-~ing and heeling tanks ana an anti-icing system in-corporating at least two air manifolds with openings for blo~ing the air out, a centrifugal compressor with a die-sel drive and a pipeline used to supply the air into -the air mani~olds, - '~he air manifolds are arranged along the ship hull symmetrically with respect to the ~ore-and-aft line below the waterlirLe at a depth ~` approximately 5G per cent of the draught o~ the ship, and are fastened to the inter-nal surface of the ship hull. '~he openings used to blow out the air are made in the ship hull (US Pa~
tent No.3,580,204, patented in 1978).
~ he anti-icing systems o~ both the prototype ship and the analogous ship do ~ot provide direct pneumatic ~low along the bow extremity of the ship because of the drift of air bubbles towards the ship ster~.
~ he air manifolds arran~ed insid~ the ~hip hull and ", ~

the openings for blowing the air out ~ade in the ship hull force the air bubbles to li~t in the immediate vicinity to the ship hull. ~his fail to provide a material thickness of layer o~ the sea water liI~ted by the air/ not allowing, in turn, to improve the e~iciency of the pneumatic fl~
alon~ the ship an~ her propulsive guality in ice.
FuI~hermore, the t~perature of the air dawnstream from the compressor does not exceed the level determirled by heating of the air in the course of compression in the compressor, whereby the specific volume ol` the air blown out, that is the buoyancy force aeterlliining the velocity and the amount O-T` t~le sea water lifted at the available capacity OI` the compressor, is minimum. ~r~his also does not allow to improve the efficisncy of the pneu~atic ~10VJ
and, hence; -the propulsive quality of the ship in ice.
The openin~;s used to blo~ the air out made below the wa-terline at a level OI' approxi~tely 50 per cent of the draught of the ship, do not all~v to provide a flow along the hull surface ~rom a depth down to 100 per cent of the ship draught. ~his also diminishes the ef`ficiency of t~e pneumatic fl~.
~ he use o~ the diesel engine as a compressor drive leads to the necessity either to equip the ice-ship wi-th an additional diesel plaut or to take the power off from the propulsion-machinery plant of the ship.
Thus, the anti-icing system o~ the protortypeice-ship does not provide the eflicient pneumatic flow along the hull anl, hence, does not pre~ent its frosting-up.
The ~`ros-tin~-up o~ the ship hull ca~ lead -to freezing o~
water in the -tri~ming and he~lir~ tanks7 reducing the eff-iciency of the ship operation.
Summary of the Invention It is a~ object o~ the present invention to increase tne propulsive quality of the ship in ice.
A~other object o~ the present invention is to pro-vide an ice-ship with reduced ener~J expenditures for the pneumatic flow.
Still an other objec-t ol~ the present invention is to improve efficiency o~ the ship s-team-enerating plant b~
utilization o~ the waste s-team.
~DI) )~
`;iitn these a~d other obàects in ~iew there is .
~e~ an ice-ship comprising a hull, t.rimming and heelin~
tanks and an an-ti-icin~ system incorpora-tin~ a compresso~
with a drive, at leas-t two air mani~olds with openin~s used to blow the air out arran~ed below the waterline sy~m-etrically with respect to -the fore and-aft line alon~ the ship hull an~ connected with -the compressor by means of`
a~ air supply pipeline, wherein, in accor~ance ~vith the present in~ention, -tLle air ~anifolds OL the anti-icin~
system are fastened to the external surYace o~` the ship hull in the bildge portion thereo~7 while said openi~gs used to blow the air out are made in the lower portion o~` the air mani~old, the anti-icing sys~e~ being pro~ided with two additional air i~ niIolds arran~ed along the ship stempost below the waterli.~e, fastened to th0 ~hip hull symmetrically with respect to the ste~post in the immediate vicinity thereto, connected to the air suppl~
pipeliney and provided with ope~ings to blo~ the air out, whose diameter increases as they approach the hull bottom~
a~ a-t least one air heater is arranged in air supply pipeline.
~ he air manifolds arranged along -the ship hull on the external surIace thereof anl -the openings arranged in the lower por-tion of the air manifolds alluw to increase -the thickness of -the sea water layer flowing along the ship hull anl lifted by the air, by -the value equal to tne air ~anifold width, thus adding to the intensity of the pneu-matic washing of the ship an~, hence, to her propulsive quality in ice.
~ urthermore, the provision of the openings for ~lowing out -the air in -the lower por-tion of the maniflods allows to prévent their clogging with ice, im~ro~ ng the reliab-ility o~ the compressor and the anti-icing system as a whole.
~ he main~olds arranged in the bildge portio~ of-the ship hull provide~ washing o~` the entire ship surfac~ be-low the waterline, -that is 100 per cent of the draugh~, thus, increasing the e~iciency ~f tLle pneumatic flo~.
The additional air manifolds arranged along the ship stempost in the immediate~vioinity there~o provide ~sning of the bow extremity ~ the ship hull where the fr~ing--up o~ the ship is~ as a rule, started, This also imp-ro~es the propulsive quality o~ the ship in ice/
The provision o~ openings for blowin~ ou-t the air in the additional manilolds, the diame-ter OI~ the openings increasin~ as they approach the hull botto~ provides a uniform air distribution among the openin~s.
~ he air heater provided in air supply pipeline allows to increase the volumetric air flo~J rate while its wei~ht ~lo~ rate is maintained constant and, thus~ to additionally increase the thicXness o~ the lit-ted sea water layer. ~hi~ increases ~`urther the inte.usity of the pneuma-tic flow along the ship hull and hence, inlpro~es the propulsive quality o, the ship in ice.
I1'ur-ther~ore, i-t is OI` _ar-ticular impor-tance to blow out ~he heated air in case t~e air maniIolds are faste~ed to the external sur-iace o~ ~he ship since the exterr~l manifolds are cooled Iaster than the manifolds on the internal surIace ol the ship an~ cold air is blown out, it is probable -that their openings become frc~en.
This can lead to a decrease in the ef`~iciency o~`-the pneumatic ~l~q.
It lS advisable to arrange the addi-tional air manifolds o~` the anti-icing system on the internal sur~
`ace of the ship hull an~ to proYide their openin~s ~or blowing the air out in the ship hull.
The additional manifolds fastened to the internal ~ur~ace o-f the ship hull are advisable for ships operat ing under particularl~ heavy ice conditions when string ent require~en~s are pla2ed upon the reliabilit~ o~ the hull s~ructures.
Acc~rding another embodimen~ o~ the presen-t inven-tio~, the additiorlal air manifolds oY` the anti-icing sgs-tem are fastened to tLle external surface o~ the ship Lull while the openings used to blow the air out face the ship hull bottom.
~ astenin~ oi the additional manifolds to the exter-nal surface OI` the ship hull is advisable ~or transport ships an~ operating ice-breakers.
According to one ol the embcdimen~s o~ the present in~ention the air heater OI the anti-ici~ systema in-stalled in the air supply pipeline is arranged a-t ~he compressor inlet.
Such an arranOement or~ the air heater is advisable for ice-shi~s opera-ting at an ambient air tempera-ture from 0C al~ bel~v, since the heatin~ o~` the air in the compressor receiving cha~nel reduces -the probability o~
ice formation on inlet compressor compo~ents, thus imp-ro~ing the reliability of the compressar as a whole.
In accordance ~-th another embo~ime~t of the present in~ention, the air heater o~ the anti-icing system, in-stall2d in the air supply pipeline is arranged at the compres~or outlet.
Such an arrangeme~t o~ the air heater is advisable for ice-ships opexatinO at an aulbient air temperature from 0C to ~10C, that is when there is no probability o~ ice formation on inle~ compressor compone~-tsO
In accordance wi-th still another embodiment oY the present invention one the air heaters o~ the an-ti~icing system, installed in the air suppl~ pipeline is arranged a-t the compressor inlet, while the o-ther~ at the compres-sor outletO
The arrangement of the air heaters at -the compressor inle~ ani outlet is advisable f`or ice-ships op~rating at an ambient air temperature from -50C to *10C.
In accordance with th.e presen-t inven-tion it is a~-visable that tne drive of the anti icinæ~ system compressor be embodie~ as a steam turbine coupled, as to -the was-te steam, ~-th the heater of ~he air supplied in-to the air ~nanifolds The compressor drive made as the steam turbine all-ows to use the steam available i~ the main steam-power plant of the ship~ 'rhis reduces the economic and energe-tic expenditures ~`or the pneumatic washing associate~
~vith installation of` a sel~-contained co~pressor drive.
Furthermore, the use o~ the steam -turbine as a compressor drive allows to utilize the heat of the waste s-team, enhancing -the ef~iciency o~ the main ship s-team-generating plant.
In accor~ance with one of the embodiment 8 0~` the present invention the steam turbine of the anti-icing system is additionally coupled, as to the waste steam, with the trimming arld heeling tanks.
The couplinO f the s-team turbine with -the tri~mi~g anl heelin~ tanks allo~s to heat the v~ater in said tanks, preventing its freezing. This improves the re-liability of tri~ming and heeling of the shlp.
Furthermore, the heatin~ of the ~7ater in -the -trimm~
ing and heeling tanks allows to elevate the ship hull temperature~ This der~li~ishes, in turn,-the frostinO-up of the ship hull ar~, hence~ improves i-ts propulsive qua-lity in ice.
Cther and further objects and advan-ta~es o~ the in-vention YJill be ~e-tter unders-tood ~rom the follo~ing de-scription taken in conjunction wi-th tL~e accompanyin~
drawinOs illustrating preferred eLLIbodirneNts of the inven--tion, wherein:
Brief Description of the ~rawings Figo1 is a diagramatic top vie~7 of ~e ice-ship in accordance with the present invention;
Fi~.2 is the same as in ~ig.1, si~e view;
Fig~3 is a cross-sectional vie~ of one embodiment of the air l~anifol1;
Fig.4 is a c~oss sectional vie~J of another embodi-~ent OI` the air .manifo ld;
~ ig.5 is a diaOra~tic side view of another embodi-ment of ~he ice~ship;
Fig.6 is a diagrama-tic side vie~ of s-till an other embodi~e~t of the ice-ship;

Fig~'7 is -the same as in E'ig.6~ -top view, Fig.8 is the same as in Fig.5~ top view.
Detailed Description OI the Invention Re~erring llOW -to the accompanyin~ drawin~s and namely to Fig o1~ the ice-ship comprises a hull 1 accommo-dating two tri~ming tanks 2, two heelin~ tanks 3, a main ship steam-power plant 4 incorporatin~ a throttling de-vice 5 and a deaerator 6~ anl a~ an-ti-icing sys-tem in-cluding a compressor 7 ~hth a drive made in the ~orm o~
a steam turbine 8, two air r,anifolds 5 with openings 10 to blow the air out 9 arranged bel~/-the waterline (~) symmetrically with respect to the Iore-and-a~t line along the hull 1 of the ship, -two air li~nifolds 11 ~th open-ings 12 used to blow out the air 5 arranged along a stem-post 13 of` the hull 1 ~ -the ship, a pipeline 14 wQth taps 15 used to supply th~ air in-t~ the air ~ai~folds 9, 11 from the compressor 7, and an air heater 16.
'~he compressor 7 OI' the anti-icing system is made as a~ axial~ one, bu-t other types o~ the compressor 1 may be also used.
'~he s-team turbine 8 which is used as a drive o~' the compressor 7 o~ the anti-icing system in ice-ships in which main power plant is a steam power one, allows to use the steam energy o~` the main ship s-team power plant 4 to provide tne pneuma-tic ~low along -the hull 1 o~' the ship.
'~he s~eam turbine 8 is connecte~ in parallel with the throttling device 5 of the main ship s-team power pla~t 4.
Re~erring now to Fig~2 3 the air ~anifolds 9 are forMed by shaped members ~astened stiffly to the external surface o~ the hull 1 o~ the ship in her bildge porti,on 17, and by the hull 1.
The length o~ the air manifolds 9 is approximately two thirds of the length of the hul'l 1 o~ the ship.
r~he air I~nifolds may be of trian~le or semioval shape in cross-section (Fig.3 anl 43.
~ he shape o~ the cross-sec-tion ~L' -the air manifold 9 is chosen dependin~ upon the purpose o~' the ice-ship.
So, ~'or example, ~or ice-breakers operatin~ under bea~y ice condi-tions it is advisable to employ the alr manifolds 9 (I1`ig.4) ha~in~ the semioval cross-section, providing a higher stre~gth a.nd a better stream- line form~
For transport ice-ships operatin~ under easier ice conditions, even frequently in clear water, it is advisab-le to use the air mani~old5 9 (h`ig.3) having triangle cross-section, which is less stronO ~ but simpler in ma-nu~`acture . In transport ships~ the air ~anif'olls 9 may serve -the function ot` passive ship stabilizers -'bildge keels.
~ ne width o~' the air manifolds 9 chosen from the condition o~ optimal hydraulic resis-tances and the uni-f orm ai r distribution.

The air manifolds 9 (Fig.1, Fi~.2)~etheopenings 10 used to blcw the air, out arral~ed alo~ the entire len~th o~ tlle air ~anifoJd ~ in the lo~Jer portion thereof~ '~he openin~s 10 face a bo-t-tom 1~ o~ the hull 1 o~' the ship.
This allows the clo~ginO 0~ the openin~s 10 ~.~th ice to be avoided.
~ he diame-ters of the openings 10 are from 0.1 to.1.0 of t~e width (H) o~ the air ~ni~olds 9.
Ths spacin~ be-tween the openinOs 'l0 (.~i~.1) is ~rom 0.2 to 0.4 o~`-the ship draught. ;~his provides complete washing of the entire hull 1 o~ the ship i~l the area OI' the waterline (B~).
'l'he ai.r manif`olds 9 are coupled wit'- the co~llpressor 7 by the ~ir SL~PP1Y pipeline 14.
As shown i~ FiD~5~ iI t'ne ice-ship is provided with ice boxes 19 which recei~e v~ater above the bildge por-tion 17 o~ the hull 1, then -the air ~anifoJd ~ rounds the ice bo~es 19.
If` the ship is provided ~th the ice boxes 19 recei-ving the .~ater in t~ie bildge por-tion 17 OI` -the hull.1 then three ~lOt interconnected air manifolds 9 (Fig-6, Fig.7) are installed sy~metrically with respect to the fore-and-aI't line, -the ice boxes 19 b'ei~ arranged there-bet~een.
In the above mentioned elllbodime~t OI' the anti-icing system, the air supply pipeline 14 is coi~nected ~th the air l~nifolds 9 b~ means OI~ the taps 15.
1b The air manifolds 11 arranged along the stempos-t 13 OI' the hull 1 o~ the ship are ormed by shaped members fastened to the in-ternal surface of the hull 1 o~ the ship symmetrically with respect to the stempost 1~ in the l~media-te vicinity thereto, anl by -the surfaces OL` -the hull 1 of the ship~
l~he air manifolds 11 have the sa~ne ~th and cross section as the air manifol~s 9.
'rhe lenOth ot -the air manifolds 11 is equal to the distance from the waterline (B~) to ~he bild~e portion 17.
The openings 12 used to blow -the air out from the air ~aniiolds 11 are made in the hull 1 alon~ the en-tire length OI` the air manifolds 11 anl have a spacin~ equal to 0.1 to 0.3 OI` the ship draught.
'l'he diameters o~` the openings 12 increase as the openings 12 apr~roach trle bottom 1~ ~r` -the hull 1 and range ~rom 0.04 to 1.0 of the width (H) o~ the air manifolds 11.
Such openings 12 allow the air to be uniformly dis-tributed a~on~ -the openin~s arranged a~ a di~erent de,th.
'~he air manifolds 11 fastened -to the internal sur-~ace o~ -the hull 1 of the ship areadvi~able for the ships operatin~ in particularly heavy ice condi-tions when stringent requirements ~replaced upon ~he reliabili-ty o~
the hull structures.
The air ~anifolds 11 are connected with the pipe-line 14 by means OI' the taps 15.

IQ the event it is necessary to install the air manifold 11 in -the ships which are already in serv.ice, while their cons~ruction features of the hulls 1 and the dimensions of the ~raming o~ t~le stempost 13 do not allow two air manifolds 11 to be positioned ~i-thout impairing the ship s-treng-th, one air manifold 11 (not shown) is installed. ~he openings 12 are Inade în this case in the hull 1 on both sides wi-th respect to the stempost 13.
~ he air manifol~s 11 are connected with the air slpply pipeline 14 by means of the taps 15.
In accordance wi-th the preserlt invention, -the air maniYolds 11 (Fi~s 5~hr~! 8) can be fas-tened to the ex-ternal sur~ace o-~ the hull 1 OI tile snip- This is ad-visable for -transport ice-ships anl ice-breakers that are already in ser~ice~
. In ~i~s.5 -through 8 and in Figs.1 through 4~ like reference nu~erals refer to like parts OI the ice-ship.
The air manifolds_ 11 fastened to the external sur-face o~ the hull 1 o~ the ship ha~e semioval cross-sec-tlon fea-turi~ a higher streIl~-th.
A variety of el~bodiments are possible for -the air mani~olds 11 ~astened to the external surface o~ the hull 1 of the shipr ~or example, Figs.5, 8 illustra-te the air manifolds 11 fastened to the external surface of t~e hull 1 of the ship9 -that are stiffly col~ec-ted to and communicate with the air mani~`olds ~; an~ ~ve a common air s~pply with t~e air manifold 9.

Figures 6~ 7 represent the embodiment of the ice-ship havlng not interconnected air inani~'olds 9 a~1 11~
The air ma~ifolds 11 are connected with the pipe-line 14 by means o-~' the taps 15.
In the air ~Lanifolds 11 -fastened to the ex-ter~al surf'ace of the hull 1, the ope~in~s 12 ~'ace the bot-tom 18 of the hull 1 and have -the same diameters and spacin~ as the openings 12 (r~'ig.1) irL the air manifolds 11 ~astened -to the in-ternal surface or the hull 1.
~ o~ever3 when the air mani~'olds 11 (Fi~ io.~) are fastene~ to the e~ternal surlace of the null 1 and are con.~ected. wi-th -the air -~nifolds c, ~the diameter o~' lar_~er openinO 12 o~` each o~' tLle air ~anifolds 11 s~lould be smaller than -the diame-ter or t-L-le opeaint; s 10 OI` the air mani~'olds 9. ~'his provicLes a uniform distlibution of the air al~lon~ tre op~nings 10, 12.
~ 1~L1e he..ter 1~ (~ig.1) OI` the air o, -the anti-icinO
sys-tem, installe~ in the aiI suppl~ pi~eline 14 is ma~e, for ~xa,n~le, as a heated pl~te--type se~arator, is arran~ed at an inlet oL tile compressor 7 and is couple~
~.vith tile st~am tuI~bine ~ as to the .vaste steam. Lhis provides ~loatinO o~' tLe tlea-teI 16 ~rith tL1e waste ste~L
o~ the tur~in~ 8, i.t?. tile ile~t of -t-le li~in ship Ste-L:L-power ~lan-t 4 is utilized.
TLle use o~ the heater 1~ a-t tLLe inlet ol the co~.p-ressor 7 is a~visable ~or ice-ships o)eratin~ at an air te~eera-t~lre IrO~L 0C and below.

In accordance wi-th the presen~ invention~ other ver~ions ~fethe arrangement of the heater 1~ ~ the air in the pipeline 1,4 used to suppl~ the air to the air ma-nifold~ 9, 11 are possible.
Shown in Fi~.7 i~ the ice-ship having tae hea-ter 16 arranged at an outle~ of the compressor 7. '~his is advi-sable ~or ships operating at an air temperature from ~C
to -~10C.
In accorda~ce with ano-ther embodiment of the inven-tion represented in ~'ig.8, the air heaters 16 o~ the anti-icing system are arran~,ed at the inlet and at the outlet OI the compressor 7. 'rhis is advisable for ice~
ships operatinO at an air -te~.^,perature from -50C to ~10C~
In accordance with still f.urther e~bodi~nent o~ tne invention, it is advisable to co~nect the steam turbine 8 ~Fig.8) with the tri ,rning tanks 2 and the hsaling -tanks ,~, as to the ~arte steam. '~his preven-ts ~reezing of the water therein.
'~he anti-icinO system of the ice-ship operates as ~ollo~,~ls .
The steam of the l~ain ship ,steam~power plant 4 .1) is supplied to the inlet branc~l ~ipe (not sho~) of the steam turbi~e 8 rotatin~ -the coinpressor 7.
The waste steam of the s~e~n turbine ~ is ~ed ~or utili~ation; for heating the air in the heater 16, for heatin~ -the water in the tri~nin~ tanks 2 anl i~ the heelinO tanks 3, and for heating -the ~ater in -t~e d~aera-tor 6.
- ~0 Th~ ambie~t air pZ~9i~; through t~e air ~uppl,y line 14 a~d through tbs ~ir h~ater 1~ i9 suppliad i~to the cnmprassor 7 at a tempar~tur~ hi~her t~a~ t~e aklaDspbs-ric temperatuxe b~y 5 to L~C.
If the aix heater 16 i 9 ~ot in~tallad at the i~let OI tha compr~ssor 7 (Fig~ 7~ 9 tl~e air i~ suppli~d into the compr~s~or at an atmospherlc t~mperatllre.
I~ th~ cour~e OI air compre~iDn~ at th~ oll~let of the compressor 7 (Fi~. ~1) it~ temperaturs beeome~ higher than the t~mperaburc o~ air at the inlet o~ thfl compres 30r ? b~ 60 to 100Cg a~d tbe air pre~sure r~ise~ to 108

2.5 atm (ab~.
The compressed a ir i~ f~d by the cD~pressor 7 into ths air suppl~ pipeli~e 14.
IX at the outleb oî tbe compre~sDr 7 (Fig . 7 ~ 8), is installed th6 alr heater 16 tha oompre~sed air is additio~ally beated by 5 t~ 40C before it e~ter~ thQ
pipsline 14. A~ a result, the volumetric flow rate o~
tbe alr is increased without irlcr3~se ln i t9 welght flow rate .
~ he compre~ed air at a temperature Df 110 to 180Ct a pressure of 108 to 2.5 abm (ab~ and in the amount Df 10 to 30 m3/~ l~ 9upplled tbrougb ~e pip~liue 14 ~Flg. 1) i~to th~ sir ma~ifold~ 9 arranged. alon~3 the hull 1 o* the ~hip a~d thxougb th~ taps 15~ into th~ air ma~i~old~ 11 arx~nged a t the ~tempo~t 13 of the ~blp,.
I~ tbe embodlme~ts illu~trat~d i~ ~g~O 5 through 8, --21_ the air is supplied into the air manifolds 9, 11 from the pipeline 14 through -the -taps 15.
'rhe air distributed uniformly among the openin~s 10, 12 is blo~ out overboard ~hrough the openings 10, 12 o-f -the air mani~olds 9, 11~ respectivel~, bel~q the water-line, e~bracing -the e~tire surYace OI the ship ~'rom the s-tempost 13 to the stern.
Air bubbles ascend to the water surface, generating a s-txong, upward Ylow of` -the sea water at the hull 1 ~`or the en-tire draught OI -the ship.
The deep sea water itselI` has a temperature higher than -the temperature of the suxface wa-ter, while the deep sea ~ater heated by the hot air bubbles ar~ liI`-ted to -the sur~ace all the more wets an~ melts the ice in the co~--tact region with the ship, thus pre~enting sticking ~
ice an~ snow to the hull 1 andg hence, preventin~ the Yrosting-up of -the ship. h~urthermore, the ~riction bet-ween the ice and the hull 1 o~ the ship is reduced.
The thickness of the deep sea water layer bein~
ted is maximum since the air bubbles ascend no-t in the immediate vicinity to the hull 1 as the proro-type, but at a dist~lce equal to the width OI` the air mani-Yolds 9, 11. Further~ore~ the air heated in tha air heater 16 has a higher ~olume-tric flow ra-te. '~he ~aximum t"iGkness of the layer OI' sea water washing intensi~ely tàe hull 1 of the ship allows the propulsive quali-ty o~
~he ship in ice to be i~proved~

Thus~ in the proposed ice-ship the hull 1 is comp-letely washed and maximura thickness o~ the saa water layer being lifted is pro~ided, This allows the propul-sive qualitJ of the ship in ice -to be ma-terially irnpro-ved.
iU As it was mentioned hereinabove, in -the ~ 4}~
ice-ship the anti-icing s~stem provides for the utiliza-tion o~ the waste ste~a o~ the steam turbine 8.
So~ when the steam turbine 8 is connected with the air heater the latter is heated by the was-te steam. This provides for ~inimum energy expendit~res for heatin~ .
air I`or pneuma-tic flow washin~ the hull 1 o~ the ship~
I~. the steam turbine 8 (Fig.8) is connected with the trimmirl~ tanks 2 an~ tne heelin~ ta~s 3, -the ~Jater in said ta~ks is heated by the waste steam o~' the steam turbine 8. ~his prevents freezing oY -the water, improves the e~`ficie~c~ o~ the trimming and t~le heeling of the ship and, hence, i~aproves the ef`Iicienc~ of ship opera-tion in heavy ice.
Furthermore~ the heated water in said ta~ks 2 t in-creases somewhat the telaperature OI the hull 1 of the ship. This also reduces, ~l~ostin~-up o~` the ship and, hence, improves her propulsive guality in ice.
The connection of -the steam turbine 8 (Figs~1, 7, 8) in parallel with the throttle 5 allows to use the waste steam OI ~he stea~ ~urbine 8 for heati~g the water in the deareator 6. The live steam of the ~ain ship steam power plant 4 is used for hea-ting the water in the dearea-tor 6 only when maximum power of the main ship steampower plant 4 is developed.

Thus, the utilization of the waste steam of the steam turbine ~ increases the efficiency of the main ship steampower plant 4 and reduces the energy expenditures for the pneumatic flow along the ship.

The construc-tion of the ice-ship with the anti-icing system opens -the way to improve her propulsive quality in ice, to reduce the energy expenditures for producing the pneumatic flow along the ship hull and to enhance the efficiency of the main ship steampower plant.

Claims (8)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. An ice-ship comprising:
- a hull having a stempost, a bottom and a billdge portion, - trimming tanks installed is said hull, - heeling tanks installed in said hull, - an anti-icing system installed in said hull and incor-porating:
- a compressor with a drive, having an inlet and out-let, - at least two air manifolds arranged below the water-line symmetrically with respect to the fore-and-aft line along said hull of said ship and fastened to the external surface of said hull in said bildge portion thereof, - openings used to blow out the air, provided in the lower portion of said air manifolds, - an air supply pipeline connecting said compressor with said air manifolds.
- two air manifolds arranged along said stempost be-low the waterline, fastened to said. ship hull symm-etrically with respect to said stempost in the immediate vicinity thereto and connected with said air supply pipeline, - openings used to blow out the air, provided in said air manifolds arranged along said stempost, the diameters of the openings increasing as they app-roach said bottom of said hull, - at least one air heater installed in said air supply pipeline.

2. An ice-ship as defined in Claim 1, wherein said air manifolds of said anti-icing system, arranged along said stempost of said ship hull are fastened to the in-ternal surface of said ship hull while said openings used to blow the air out are made in said ship hull.

3. An ice-ship as defined in Claim 1, wherein said air manifolds of said anti-icing system, arran-ged along said stempost of said snip hull are fastened to the external surface of said hull while said openings used to blow the air out lace said bottom of said ship hull.

4. An ice-ship as defined in Claim 1, wherein said air heater of said anti-icing system, instal-led in said air supply pipeline is arranged at said inlet of said compressor.

5. An ice-ship as defined in Claim 1, wherein said air heater of said anti-icing system, installed in said air supply pipeline is arranged at said outlet of said compressor.

6. An ice-ship as defined in Claim 1, wherein said air heaters of said anti-icing system, installed in said air supply pipeline are arranged so that one of them is at said inlet of said compressor while the other is at said outlet of said compressor.

7. An ice-ship as defined in Claim 1, wherein said drive of said compressor of said anti-icing system is made as a steam turbine coupled as to the waste steam with said heater of the air supplied to said air manifolds.

8. An ice-ship as defined in Claim 7, wherein said steam turbine of said anti-icing system is coupled as to the waste steam with said trimming tanks and said heeling tanks.