Conventional propellers in CRP-POD configuration. Tests and extrapolation.

Transcription

1 ifth Iteratial ypsiu Marie Prpulsrs MP 17, Esp, ilad, ue 017 vetial prpellers i P-PO cfigurati. ests ad extraplati. aó uereda 1, Maria Pérez-bri, ua Gzález-Adalid, ristia ria 1 1 Ita-ehipar, aal de Experiecias Hidrdiáicas de El Pard, Madrid, pai istear, Madrid, pai ABA A P-PO prpulsi syste ccept is explaied ad the challeges related t testig at del scale are preseted. P-PO cfigurati icludes tw differet prpulsrs arraged i lie with a shrt distace i betwee the, ad csequetly a high iteracti is expected. he full per is divided it tw parts. Each uit prvides a percetage f the ttal per. It is quite c 60-80% fr the ai egie ad 40-0% fr the PO uit. Hull resistace test is carried ut i the sae way tha i ay ther prpulsi cfigurati because this prpulsi syste is csidered as a uit. everal pe water tests (OW) ust be carried ut t k the thrust ad trque f bth prpellers i differet situatis. PO uit resistace is als deduced fr OW. ad paraeters are defied i a differet way by csiderig that the rp f bth prpellers are differet. carry ut OW ad self prpulsi tests i the tig tak tw idepedet dyaeters are ecessary. pecific devices have bee desiged ad aufactured t carry ut the del tests. he paper describes these tests ad the device arrageet develped ad aufactured at EHIPA ecessary t test the uit i a tig tak. A geeral extraplati ethd with cvetial type prpellers is preseted ad applied i detail t a case studied i a & prject fuded by EU P6. eywrds Prpulsrs, P-PO syste, PO husig, del testig, scalig prcedure. 1 INOUION he s called P-PO which is a ctra-rtatig prpellers cfigurati icludig tw differet prpellers arraged i the sae geetrical shaft with a shrt distace i betwee the ad rtatig i ppsite sese but with a specific drive syste. urig the last decade the iterest P-PO uits has icreased. I particular a case f P-PO syste was used i the & prject supprted by the EU-P6, IPO (áchez aja et al 01), that was develped fr 010 t 01 ad all ecessary tests were carried ut at EHIPA facilities. It was ecessary t desig ad aufacture specific devices t carry ut the del tests. Part f these develpets has bee already preseted i 10 th IH (uereda et al, 01). he cplete prcedure t test this kid f uit is preseted i this paper icludig device arrageets, del testig ethd, extraplati prcedure, test results ad extraplati applicati. Existig I prcedures have bee take as a basis t develp a ew extraplati ethd allig the predicti f the perfrace f a real ship prpelled with this prpulsi syste. Mai uerical data f e case icluded i IPO is als preseted here t facilitate the cprehesi f the ew testig ad extraplati prcedure prpsed. It crrespds t a del f a 8,500 EU ctaier ship tested i IPO prject at the scale f P-PO YEM EIPION A P-PO cfigurati icludes tw differet prpellers drive by separated egies ad arraged i lie with a very shrt distace i betwee the, ad csequetly a high iteracti ust be csidered. he ai egie drives the frward prpeller ad the aft prpeller actuates separately ad it is drive by a electrical egie arraged iside the PO uit ad rtatig i ppsite sese. As i ther P systes the ai is t recver i the aft prpeller the rtatial eergy lsses f the ai prpeller. his syste alls reachig higher per vessels splittig the full per it tw parts. Each uit prvides a percetage f the ttal per. It is quite c 60-80% fr the ai egie ad 40-0% fr the PO uit. A P-PO syste has itrisically re degrees f freed tha a cvetial prpulsi syste aily depedig the egies ad drivig arrageets. I the case studied here the electrical tr, drivig the PO prpeller is cected t a electrical geeratr (PO) allig t establish a fixed relati f rp betwee ai ad PO prpellers. I this case the value f 10/14 was established.

2 he PO UNI tested is the s called UE-PO develped by ABB which has t the pssibility f rtati arud its vertical axis. hip aeuvrability will be attaied by eas f a large flap actig as a rudder istalled i the PO uit. E POGAM he test prgra icludes resistace, pe water with differet cfiguratis ad self prpulsi tests. carry ut the tests i the EHIPA tig tak, it was ecessary t desig ad aufacture specific devices, as sh i figures 1 ad. he whle prpulsi syste is csidered as a uit. carry ut OW ad self prpulsi tests i the tig tak tw idepedet dyaeters are ecessary. he dyaeter crrespdig t the ai prpeller will easure the thrust, trque ad rp f the ai prpeller, while the dyaeter f the PO uit igure 1 will easure the thrust, trque ad rp f the PO prpeller ad a additial lad cell alls t easure the ttal thrust f the uit, UNI..1 esistace est he resistace test has bee carried ut withut the PO uit, i bare hull cditi, see igure, as it is receded i the I prcedure, because the PO husig is a part f prpulsi syste ad it is t csidered as a appedage., this test is carried ut fllig the stadard prcedure icluded i I`78- PPM. he fr factr k has bee deteried accrdig t Prhaska s ethd by usig the resistace f the del easured at l rude uber values. he residual resistace cefficiet is btaied fr the calculated ttal resistace cefficiet f the del ad frictial resistace cefficiet which is calculated accrdig t I-57 fricti lie. ( 1 k) (1) he ttal resistace cefficiet is btaied fr the calculated fricti resistace cefficiet accrdig t I-57, the residual resistace cefficiet btaied fr Equati (1), the ski fricti crrecti ad the cefficiet AA. ( 1 k) () AA igure 1. PO husig ad PO dyaeter. he arrageet f PO dyaeter t carry ut self prpulsi tests is sh i igure. igure. Arrageet t carry ut self prpulsi test. elf prpulsi tests were carried ut aitaiig cstat the rati f the rp betwee ai ad PO prpeller at each velcity. Lad varyig tests were cducted t deterie the self-prpulsi perati pit. igure. ter f the ship del t carry ut resistace test. Withut appedages.. Ope Water est I suary, a P-PO syste is cpsed f the ai prpeller ad the PO uit; this, i tur, csists f PO husig ad PO prpeller. ifferet Ope Water ests (OW) ust be carried ut t deterie the prpulsi syste characteristics f each idividual prpeller, their iteractis ad the ifluece f the PO husig. Bel it is explaied all the OW with ai ad PO prpellers i differet cfiguratis. I all OW the shaft f the prpellers ust be iersed 1.5 ties the diaeter f the ai prpeller...1 Mai prpeller ale I igure 7 the cfigurati f the P-PO syste i Ope Water cditi shs that ai prpeller is tested i reverse fl cparig with stadard OW. I rder t check if the shaft f the prpeller dyaeter ca have ay ifluece, ai prpeller has bee tested i bth cditi, ral ad reverse fl, igure 4. It was ccluded that beig the shaft large eugh there was t ifluece the ad values fr values clse t the desig pit, s sall wake field effect has bee eglected. ub-idex P is used t be referred t the ai prpeller, has bee used fr the del ad super idex is used t idicate that the prpeller has bee tested ale, as it is

3 sh i igure 4. N-diesial paraeters btaied fr this test are: V ().. PO prpeller ad PO husig As the PO husig is a part f the PO uit, a OW f the PO uit as a whle ust be carried ut. he PO prpeller shuld rtate at the sae rp tha i the pe water carried ut with the PO prpeller ale. (4) 4 5 (5) (6) Where eas advace cefficiet, V velcity f the del, del prpeller rps, prpeller diaeter, thrust cefficiet, thrust easured, trque cefficiet, trque the prpeller axis ad water desity. is the pe water efficiecy. igure 4. re prpeller. Ope water tests. Up, ral psiti; d, reversed fl... PO prpeller ale ub-idex AP is referred t the PO prpeller, r after prpeller i this cfigurati, ly tested i ral psiti, as it ay be bserved igure 5. igure 5. Ope water test. Aft prpeller. V (7) 4 5 (8) (9) (10) igure 6. Ope water test. Aft prpeller i the PO husig. he PO husig is lcated dstrea f the PO prpeller durig the test. he plate situated ver the PO husig, igure 1, ust be ver the water surface, s the ar ust be large eugh t perit that the del prpeller be iersed 1.5 ties the diaeter f the ai prpeller. he PO dyaeter alls t easure the PO prpeller thrust ad the ttal thrust f the PO uit UNI. he drag f the PO husig is deduced as the thrust prduced by the PO prpeller ius the ttal thrust f the PO UNI UNI. uper-idex eas that prpeller ad PO husig have bee tested tgether. UNI UNI V UNI UNI 4 5 (11) (1) (1) (14) (15) UNI..4 Mai ad PO prpeller with PO husig Oe last pe water test ust be de. he ai prpeller ad P-PO prpeller will be placed i the P cfigurati. I this test it is ecessary t aitai the sae rp rati tha i self prpulsi cditi. I the case studied i this paper, the PO prpeller rtates at the sae rp tha i the pe water test etied i.. ad the ai prpeller rtates i ppsite sese at 1.4 ties the rp f the PO prpeller. he ai prpeller has bee used as the referece t calculate the paraeters the P-PO syste

4 ig rce --> perfrace f the pe water test carried ut with bth prpellers. uper idex has bee used. V (16) A ew paraeter,, has bee defied takig it accut the ttal thrust f the syste referred t the rp ad diaeter f the ai prpeller. UNI 4 (17) Ather ew paraeter,, has bee defied takig it accut the per f bth prpellers referred t the rp ad diaeter f the ai prpeller. 5 (18) (19) 10 () 14. elf Prpulsi est urig self prpulsi test the real rp rati betwee ai ad PO prpellers will be aitaied, as it is i the case studied, beig the per develped at each prpeller a result f the test. igure. 8. Mdel ship t carry ut self prpulsi test. urig the self prpulsi test the values f PO prpeller thrust ad PO husig thrust are easured. he PO husig drag ay be deduced. UNI () Lad variatis are prduced by varyig the ai prpeller rp ; aitaiig the rp rati, the PO prpeller rp is established. Bth idepedet dyaeters all easurig rp ad trque each prpeller ad at each del velcity. A iiu f three values f are used fr each hull del speed t establish the lad variati f the prpellers. Lad Variati i elf-prpulsi est at each speed calculated igure 7. Arrageet t carry ut OW. Mai prpeller is actig i reverse fl. As i the case f Equati (11): UNI (0) calculate the PO husig del device resistace,, Equati (0) writte befre, ay be used. UNI (1) p rati f ai ad PO prpellers fr the test case is: igure 9. Lad Variati est. he self prpulsi pit is deteried iterplatig i the easured data f the lad variati test. he frictial deductis due t hull del HULL ad PO husig ust be csidered t calculate the ttal frictial deducti. HULL V P rp test --> HULL (1 k)( s) (4) (5)

5 is the fricti resistace cefficiet. fr ship ad fr del, eas desity ad is the scale factr. is the hull del wetted surface. fr ship ad fr del are deteried accrdig t I 57. educti fracti PO husig is calculated takig it accut the fricti resistace cefficiets ad fr the PO husig. eylds uber is calculated at the sae height tha the 0.75 secti f the PO prpeller ver the shaft. (6) he ttal thrust f this prpulsi syste is supplied by the thrust the frward prpeller igure, which is easured by the carriage dyaeter ad the thrust f the PO uit UNI which is easured by the PO dyaeter at each del velcity. (7) Where is the ttal thrust at del scale ad the eaig f UNI has bee explaied i Equati (). s ( 1 ) ( HULL 1 t (8) UNI UNI Where is the del resistace easured durig the resistace test i accrdace with igure, whe the hull del has t istalled the prpulsi syste. HULL ad have bee calculated accrdig t the Equati (5) ad Equati (6), respectively. is the thrust crrespdig t the ai prpeller ad UNI is the thrust f the PO uit. he del thrust cefficiet is cputed at each velcity while self prpulsi test is carried ut ad it is referred t the ai prpeller rp ad diaeter. UNI 4 ) (9) he del trque cefficiet crrespdig at the self prpulsi test is calculated at each velcity. It is referred t the ai prpeller rp ad diaeter. 5 (0) calculate w the paraeter is btaied fr self prpulsi test results, Equati (9) ad with the value, the advace cefficiet crrespdig at thrust cefficiet idetity, is read ff fr the pe water del test curves with the prpulsi syste, Equati (16) ad Equati (17). w 1 V (1) Oce deteried the value, the diesial paraeter is read ff fr the pe water del test curves with the prpulsi syste, Equati (16) ad Equati (18). akig it accut the cefficiet fr pe water del test curves ad the value btaied fr the self prpulsi test, Equati (9), crrespdig t value, the rtative-relative cefficiet culd be deteried. () 4 EXAPOLAION MEHO he prpsed extraplati prcedure is based I stadard prcedures ad it is applicable t P-PO syste with cvetial prpellers. 4.1 calig f PO Husig rag P-PO prpulsi syste is a cbiati f eleets: prpellers ad e passive PO husig structure. A part f the PO husig is peratig i the accelerated prpeller slipstrea fl ad ther part is peratig i the surrudig fl. All these eleet characteristics ust be crrected t take it accut the scale effects ad each del basi has its ethd t d it. A siple ethd is prpsed here, based the I 78-PPM exteded t the ew eleets that are preset i the P-PO cfigurati. Ope water results f bth prpellers are idividually crrected accrdig t I 78-PPM. PO husig drag, which is the differece betwee PO prpeller thrust ad PO uit thrust, is extraplated fr the del self prpulsi ad resistace test results. s s () Where is btaied fr self prpulsi test results at each tested velcity, igure, by applyig Equati (). 4. calig f Ope Water haracterisitcs Mai prpeller thrust cefficiet is used t calculate the thrust f the prpeller. 4 ( P ) (4) Where Δ P is calculated accrdig with I 78- PPM crrecti fr cvetial prpellers. 4 UNI ( UNI AP ) APAP (5) Where Δ AP fr cvetial prpellers is calculated accrdig t the I 78-PPM, ad (1 s 4 (6) he thrust cefficiet f ship prpulsi syste is calculated accrdig t Equati (4), Equati (5), I 78-PPM crrectis cvetial prpellers thrust cefficiets ad Equati (6). UNI 4 ) (7)

6 I the sae way, trque cefficiet has bee calculated. hip prpellers trque is calculated take it accut the I 78-PPM t btai Δ P ad Δ AP (8) (9) Accrdig with Equati (8) ad Equati (9) ad crrectis cvetial prpellers trque cefficiet I 78-PPM the trque cefficiet f the ship prpulsi syste is calculated. (40) (41) he paraeters, ad, Equati (41), Equati (7) ad Equati (40) all btaiig the pe water curves f the prpulsi syste fr the ship. 4. Perfrace Predicti extraplate the self-prpulsi test results, it is csidered that the thrust deducti fracti t has the sae value fr del ad full scale ship, t(del)=t(ship) ad csequetly it has t sub idex. he effective wake fracti fr the ship w based thrust idetity is extraplated accrdig with the I 78-PPM w (1 k ) t ( w t) (4) (1 k ) It is ecessary t pit ut that the 0.04 cefficiet has bee eglected because there is t rudder effect. As i the I 78-PPM, it is csidered that the rtativerelative cefficiet is t affected by scale effects. (4) akig it accut the wetted surface f the selected ship,, the lad f the full scale prpeller is btaied. (44) With this / as iput value the full scale advace cefficiet, thrust cefficiet ad trque cefficiet are read ff fr the full scale prpeller characteristics ad the fllig quatities are calculated. hrust,. AP 5 ( P ) 5 ( AP ) APAP V ( ) 4 (rps) (45) (N) (46) he delivered per. AP 5 AP (1 t)(1 w ( 1 w) V ) P he ttal prpulsive efficiecy. (kw) (47) (48) 5 APPLIAION AE A ctaier ship has bee selected as test case. Prpulsi syste P-PO has bee desiged. 5.1 Mdel characteristics Hull del ad tw cvetial prpeller dels with scale factr =8.91 were aufactured at EHIPA, pai, t carry ut the del testig prgra Hull del characteristics Legth betwee perpedicular, LPP. Mulded bea Mea draught at ballast cditi Blck cefficiet Wetted surface Mai prpeller del characteristics iaeter. Pitch at igure 10. Mai prpeller del. Pitch/iaeter rati at Nuber f blades. 5 AE/A hrd legth at hickess at V P PO prpeller del characteristics igure 11. PO prpeller del.

7 iaeter. Pitch at Pitch/iaeter rati at Nuber f blades. 4 AE/A hrd legth at hickess at est results Hull ad prpeller dels have bee tested accrdig t the prpsed prcedure ad the easureet data are preseted bel esistace test. Ballast cditi Bare hull del test results at ballast cditi are preseted i able 1. able 1. Mdel esistace. V kts N Ope water test ifferet pe water tests have bee carried ut as has bee idicated i. ad results are preseted fr able t able 5. able. Ope water test. Mai prpeller ale. 10 η able. Ope water test. PO prpeller ale. 10 η able 4. Ope water test. PO prpeller with PO husig. UNI 10 η UNI able 5. Ope water test. Prpulsi P-PO syste. 10 η elf prpulsi test. Ballast cditi elf prpulsi tests have bee carried ut as has bee idicated i. ad results are preseted fr able 6 t able 8. able 6. elf prpulsi test. efficiets. V s t w kts

8 able 7. elf prpulsi test. Prpulsi syste easureets. V kts rps N N able 8. elf prpulsi test. PO uit easureets. V UNI kts rps N N. N Extraplatis Hull del ad prpeller dels had bee aufactured ad tested t predict the ship perfrace by usig the prpsed extraplati prcedure Ope water test siderig able 5 ad Equati (7), Equati (40) ad Equati (41) ad the I 78-PPM, values f ad have bee calculated. able 9. Ope water test. hip prpeller predicti. s s 10 s η s elf prpulsi test By the applicati f the extraplati prcedure preseted i the paper, the ship perfrace has bee stablished. able 10. hip perfrace. V W P E P kts kn kw kw he splittig per btaied fr a fixed rp rati has bee calculated ad it is preseted igure 1. igure 1. Per curves f differet eleets. ONLUION A del testig prcedure fr P-PO syste fr a fixed rp rati betwee ai ad PO prpeller has bee develped. his prcedure ay be applied t ay per/rp cbiati. It is ecessary t develp idepedet dyaeters allig the easureets f idividual rp, thrust, trque ad PO husig drag i pe water ad self prpulsi cditis. A extraplati ethd fr this P-PO syste based the guidelies f the existig I stadard prcedures has bee prpsed. he extraplati prcedure has bee applied successfully t a ctaier ship tested at del scale ad predictis fr full scale have bee calculated. EEENE I, (1999). Prcedure Perfrace, Prpulsi I-PPM Perfrace Predicti Methd. I, (00). Prcedure estig ad Extraplati Methds. esistace. uereda,., Veikhei,., Pérez-bri, M., Pce,., áchez-aja, A., Masip,., Gzález- Adalid,., Uriarte, A., Nijlad, M., kkila,. (01). Mdel testig ad scalig fr P PO. 10 th Iteratial ferece hydrdyaics. t. Petersburg, ussia. áchez-aja, A., Pérez-bri, M., uereda,., Nijlad, M., Veikhei,., Gzález-Adalid,., aist, I.Uriarte, A. (01). biati f Pd, L ad P Prpulsi fr Iprvig hip Efficiecy: the IPO prject. rd Iteratial ypsiu Marie Prpulsrs. MP 1 Laucest, asaia, Australia.

9 IUION uesti fr aeg Lee Where ca we get the frictial resistace cefficiet? esistace f pd husig is easured at the prpeller with pd pe water test ad self prpulsi cditi. I full scalig, the resistace f PO husig i self prpulsi cditi is used, ad frictial cefficiet ces fr the I s flat plate fricti lie. diaeter was 8.50, ad the cvetial Pd prpeller diaeter were I ballast cditi, there was btaied a ea beefit f 4% i per i the frae 18 t kts. Authr s clsure Yes, we cfir that fr extraplati purpses frictial resistace cefficiet f PO Husig, bth i Ope Water cditi ad i elf Prpulsi tests, is calculated accrdig t I-57 frula. uesti fr Artur Nera Efficiecy beefit cpared t sigle ster prpeller. Authr s clsure Oly a case has bee aalysed deeply, a ctaier ship with a cvetial prpeller f 8.950, diaeter. I the P-PO cfigurati the ai cvetial prpeller