tag:blogger.com,1999:blog-19245896.post8140893610375781456..comments2024-03-28T21:57:32.099+11:00Comments on Submarine Matters & Australian Nuclear Weapons: Likely Specs of the Future Japanese "Super Soryu" Sub for AustraliaPete2http://www.blogger.com/profile/06134037393078707072noreply@blogger.comBlogger18125tag:blogger.com,1999:blog-19245896.post-81957226239409523682015-12-09T17:59:07.827+11:002015-12-09T17:59:07.827+11:00Hi S
Thanks for the Dec 8 information.
It is imp...Hi S<br /><br />Thanks for the Dec 8 information.<br /><br />It is important that the Super SoryuAU is as close to the (about) 3000 ton (surfaced) 29SS as possible. Too many new variables/problems will be added if the Super Soryu weighs closer to 4000 tons (surfaced).<br /><br />After all Australia seemed happy with the Australia version of the Oberon, which remained the same weight as the UK version Oberon.<br /><br />The risks and problems of creating a heavy "Super Gotland" resulted in the Collins. This has caused nightmares. But some Australian Admiral's still vainly hope for a heavy SSK with all the features of an SSN (without a reactor).<br /><br />Regards<br /><br />PetePetehttps://www.blogger.com/profile/02624742078679760819noreply@blogger.comtag:blogger.com,1999:blog-19245896.post-70578987714922718632015-12-08T23:28:15.900+11:002015-12-08T23:28:15.900+11:00
Hi Pete
Latest specialty journal of warship [1] ...<br />Hi Pete<br /><br />Latest specialty journal of warship [1] reports that 28SS (final Soryu submarine ) will equip new TCM (Torpedo Counter Measure) and sonar system as same as those of 29SS (next generation submarine). Size of 29SS will be as same as that of Soryu, because both energy consumption and risk of detectability will become bigger with increase in size.<br /><br />Comment<br />Every Soryu submarine shows minor but continuous improvement. This type of improvement will be taken over in next generation Japanese submarine.<br /><br />[1] Ships of the world, 2016, No 828<br /><br />Regards<br />S<br />Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-19245896.post-48941349694768110382015-10-09T16:58:13.556+11:002015-10-09T16:58:13.556+11:00Hi S
I have added those revised figures for subma...Hi S<br /><br />I have added those revised figures for submarine length, crew, washing machine, ladies toilet seat and bunk lengthening.<br /><br />Cheers<br /><br />PetePetehttps://www.blogger.com/profile/02624742078679760819noreply@blogger.comtag:blogger.com,1999:blog-19245896.post-14031926406266554852015-10-07T22:24:35.214+11:002015-10-07T22:24:35.214+11:00Hi Pete
I think that Japan definitely would like ...Hi Pete<br /><br />I think that Japan definitely would like to build submarines in WA/Perth, of course, they never speak to avoid diplomatic pain. Australia needs much better Quality Management System (QMS) for submarine building sector. There are two ways to improve QMS. One is reconstructing or modification of existing bad QMS, and another is constructing from zero. In the former way, we can use various existing resources, but existing factors (ineffective work habits, traditional attitude, etc) will become huge obstacles to improvement of QMS. In the latter way, we cannot use existing resources, but there is no possible obstacle, we can freely construct ideal QMS. Considering the future QMS, the submarine building by new company is better than by ASC. Perth is obviously superior to Adelaide from the point of view of distance, strategy and accessibility to submarine base.<br /><br />In the comment (October 6, 2015 at 10:43 PM), “lack of no washing machine” is mistake, “lack of washing machine” is correct.<br /><br />Regards<br />S<br /><br />Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-19245896.post-18595620229140082972015-10-07T17:55:28.722+11:002015-10-07T17:55:28.722+11:00Hi S [Oct 6, 2015 10:43PM]
Thanks for the new fig...Hi S [Oct 6, 2015 10:43PM]<br /><br />Thanks for the new figures. I will include them in a future post.<br /><br />Meanwhile there is another good The Australian article - dated Oct 7, 2015 http://www.theaustralian.com.au/national-affairs/defence/japan-language-culture-no-barriers-to-success-on-submarines/story-e6frg8yo-1227559685112 indicating:<br /><br />- in an all-Australian build Japan would start with a “mock-up” boat [very wise] called Boat Zero, in Australia to allow shipbuilders to learn how to build the new design, rather than make teething mistakes on the first boat of the fleet, as so often happens in first-of-type submarine builds. <br /><br />- If a hybrid option were chosen, whereby Japan built the first boat in Japan and the rest in Australia, there would be no need for a mock-up boat in Australia. [also has the advantage that if the Australian builds prove overly expensive/inefficient all the rest of the subs could be built in Kobe again] <br /><br />- The Japanese bid would build sustainment support centres in Japan as well as in Adelaide and Perth.<br /><br />It is still unclear in which Australia states/cities Japan would want to build sections of the sub - and then assemble. Locations are up for negotiation of Japan, with Australian companies, state governments and Federal government.<br /><br />Regards<br /><br />PetePetehttps://www.blogger.com/profile/02624742078679760819noreply@blogger.comtag:blogger.com,1999:blog-19245896.post-57834674006589829672015-10-06T22:43:16.088+11:002015-10-06T22:43:16.088+11:00
Hi Pete
Thanks for interesting information of Th...<br />Hi Pete<br /><br />Thanks for interesting information of The Australian.<br /><br />The Australian mistakes original length of Soryu, so length of 29SS mod-AUS will be 90-92m. Hull extension and abolishment of AIP will significantly contribute to improvement of the operation range and the accommodation. Also, to-be-improved efficiency of new diesel engine will have positive effect on the operation range.<br /><br />Crews of 29SSwill reduce to 59-62 by abolishment of AIP and an increase in automatization of the operation. I think that RAN is going to adopt the 3 working-shift system instead of the 2 working-shift system. The 2 working-shift system is too tough for long time surveillance of RAN. The improvement of working environment in submarine is an urgent task in recruitment activity of RAN.<br /><br />The accommodation of current Soryu is very bad such as bed 160cm (5ft 3in) long, fold type toilet and lack of no washing machine. This miserable situation, especially for women, should be improved.<br /><br />Regards<br />S<br /><br />Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-19245896.post-6505402996260157092015-10-06T16:21:33.139+11:002015-10-06T16:21:33.139+11:00Hi S
I'll you your figures [at October 6, 201...Hi S<br /><br />I'll you your figures [at October 6, 2015 at 9:23 AM] in a future article.<br /><br />Meanwhile you would be interested today's article in The Australian, http://www.theaustralian.com.au/national-affairs/defence/japan-offers-advanced-science-to-build-new-subs/story-e6frg8yo-1227558052658?sv=14d35bade45b0cc76dea8f1a422ab044 . It quotes 88m but uses it wrongly:<br /><br />"The 88m long Soryu would be extended with the ¬addition of a new hull section 6-8m long, which would be placed behind the submarine’s fin, The Australian was told in a briefing yesterday."<br /><br />By consulting Soryu in wikipedia https://en.wikipedia.org/wiki/S%C5%8Dry%C5%AB-class_submarine The Australian would have seen the current Soryu's length is 84m. A new hull section of 4m brings length up to 88m. <br /><br />The Australian article also says "[The Australian Soryu] would also come with increased accommodation for the larger crews needed on long voyages and longer bunks for taller Australians." <br /><br />As the Soryu crew is already 65 readers of The Australian can only assume the Australian Soryu's crew will be much larger than 65.<br /><br />Also in the article is: "The submarine would come with equipment from the Soryu, including a snorkel allowing it to suck in air to run its diesel engines while submerged in a typhoon."<br /><br />Regards<br /><br />PetePetehttps://www.blogger.com/profile/02624742078679760819noreply@blogger.comtag:blogger.com,1999:blog-19245896.post-43318883354111902472015-10-06T09:23:02.254+11:002015-10-06T09:23:02.254+11:00Hi Pete
I found mistake of calculation. I am awfu...Hi Pete<br /><br />I found mistake of calculation. I am awfully sorry.<br /><br />Before correction <br /><br />Speed is proportional to drag which is proportional to frontal projection area. I calculated the frontal projection areas of Collins and Soryu. Then I calculated the needed diesel fuel for 9000nm@6.5knot/h and 10knot/h from the ratio of the frontal projection area, and evaluated by figure and volume of Collins. Fuel needed for 9000nm@6.5knot/h- and 10knot/h-operation are 350t and 830t, respectively. The former value is acceptable, but the latter not. Although there are so many assumption and some possible errors, I believe that Collins submarine transfers for 9000nm at around 6knot/h and that 9000nm@10knot/h is an unrealistic value for many conventional submarines.<br /><br />(4-2)Diese fuel consumption of Collins for 9100nm@6.5kmot =Fuel consumption of Soryu x0.69=510t x0.69=350t<br />(4-3)Diesel fuel consumption for 9100nm@10knot/h=350t x (10/6.5) x (10/6.5)=830t<br /><br /><br />After correction<br /><br />Speed is proportional to drag which is proportional to frontal projection area. I calculated the frontal projection areas of Collins and Soryu. Then I calculated the needed diesel fuel for 9000nm@6.5knot/h from the ratio of the frontal projection area, and evaluated by figure and volume of Collins. Diesel fuel consumption of Collins is expected to be 550t for 9000nm@10knot/h and 350t for 9000nm@8knot/h. [1]. <br /><br />(4-2) Calculation of diese fuel consumption of Collins correspond to that of Soryu (9100nm@6.5kmot/h, fuel consumption 510t)<br />Power =Resistance x Velocity = (Resistance of Soryu) x (Velocity of Soryu) = (Resistance of Collins) x (Velocity of Collins), then,<br />Velocity of Collins =(Resistance of Soryu)/ (Resistance of Collins) x (Velocity of Soryu) =1/0.7 x 6.5knot/h =9.2 knot/h<br />(4-3)Diesel fuel consumption Collins 9000nm@10knot/h and 9000nm@8knot/h are expected to be 550t and 350t.<br /><br />[1] https://samueldavey.files.wordpress.com/2013/04/fluid-dynamics-submarine-report.pdf “Fluid Mechanics Submarine Design”, p31<br /><br />Regards<br />S<br /><br />Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-19245896.post-88404575406552537932015-10-06T01:30:04.288+11:002015-10-06T01:30:04.288+11:00Hi Pete
I calculated kerosene consumption (29t) f...Hi Pete<br /><br />I calculated kerosene consumption (29t) from amount of oxygen (100t) for Stirling AIP operation (15days@4knot/h) by using stoichiometric reaction between kerosene and oxygen. Then I compared efficiency of Stirling AIP and that of general diesel engine data, and assumed these two were nearly same. Considering kerosene and diesel fuel are nearly same substance, I assumed that diesel operation (15days@4knot/h) needed ca.30t of diesel fuel. When fuel consumption increases as square of speed, 340t of diesel is needed for 6100nm@6.5knot/h-operation, respectively. The 9100nm@6.5knot/h-operation will achieved by 4m-longer hull with additional 170t-fuel.<br /><br />Speed is proportional to drag which is proportional to frontal projection area. I calculated the frontal projection areas of Collins and Soryu. Then I calculated the needed diesel fuel for 9000nm@6.5knot/h and 10knot/h from the ratio of the frontal projection area, and evaluated by figure and volume of Collins. Fuel needed for 9000nm@6.5knot/h- and 10knot/h-operation are 350t and 830t, respectively. The former value is acceptable, but the latter not. Although there are so many assumption and some possible errors, I believe that Collins submarine transfers for 9000nm at around 6knot/h and that 9000nm@10knot/h is an unrealistic value for many conventional submarines.<br /><br />Calculation details<br /><br />(1)Calculation of efficiency of Stirling AIP in the case of Soryu<br />(1-1)Actual heat (Ha) generated by four Kockums V4-275R(4x75kW*4) for 15days -operation at 4 knot<br />Ha = 4x75kWx15day=4x75kWx 3600s=388.8GJ, where 1kW=1kJ/s <br />(1-2)Ideal heat (Hi) generated by fuel (29t-kerosene: heat capacity=36.7MJ/kg ) combustion using 100t-Oxygen <br />Hi= 36.7MJ/kg*29t=36.7MJ/kg*29*1000kg=36.7*29*1000MJ=1064.3GJ<br />(1-3)Efficiency of Stirling AIP<br />Ha/Hi x100=388.8GJ/1064.3GJx100=36.53%<br /><br />(2)Comparison of efficiency of diesel engine with that of Stirling AIP: efficiency of diesel engine is 30-40% from various data. I assumed these two efficiencies are same. <br /><br />(3)Calculation of diesel fuel consumption for 6100nm@6.5knot/h<br />(3-1)Energy (=diesel fuel consumption) increase as square to cube of speed. I assumed energy increased as square of low speed less than 10knot/h.<br />(3-2)Range for 15days@ 4knot/h=15day x 24h x 4knot/h=1440nm, and diesel fuel consumption is 30t <br />(3-3)Diesel fuel consumption for 6100nm@6.5knot/h=6100nm/1440nm x (6.5/4) x (6.5/4) x 30t=340t<br />(3-4)Needed fuel for 3000nm extension of operation=170t<br /><br />(4)Calculation of diesel fuel consumption in Collins<br />(4-1) Frontal projection area of submarine = hull area + bridge area = square of (average diameter) x 3.14/4 + bridge area<br />I assumed mast areas of Collins and Soryu are same =width 1.5m x 5m=7.5(m2)<br />Frontal projection area of Collins (Ac) and Soryu (As): Ac= 50(m2), As=72(m2): Ac/AS=0.69<br />(4-2)Diese fuel consumption of Collins for 9100nm@6.5kmot =Fuel consumption of Soryu x0.69=510t x0.69=350t<br />(4-3)Diesel fuel consumption for 9100nm@10knot/h=350t x (10/6.5) x (10/6.5)=830t<br /><br />Regards<br />S<br />Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-19245896.post-85950671988768865392015-10-05T18:25:30.303+11:002015-10-05T18:25:30.303+11:00Hi S [Oct 4, 2015 1:04AM]
While I don't unde...Hi S [Oct 4, 2015 1:04AM] <br /><br />While I don't understand all the measures of engine power I agree that KHI will need to increase engine power for a larger 29SS mod-AUS (lets call it Australian Soryu). This is considering the Australian Soryu's:<br />- larger size<br />- need for higher transit speeds than Soryu (snorting and fully submerged) and<br />- higher charging rates for Li-ion Batteries<br /><br />It is significant that the Asia Pacific Defence Reporter http://www.asiapacificdefencereporter.com/ Oct 20115 edition, Vol 41, No. 8, page 40 indicates:<br /><br />"TKMS will likely include four MTU 12V4000U83 diesels" in the Type 216.<br /><br />How many KAWASAKI 12V25/25SB's would be needed to = four MTU 12V4000U83s?<br /><br />Regards<br /><br />PetePetehttps://www.blogger.com/profile/02624742078679760819noreply@blogger.comtag:blogger.com,1999:blog-19245896.post-55417414252554192742015-10-04T01:04:28.492+10:002015-10-04T01:04:28.492+10:00Hi Pete
Ministry of Defense (MOD) does not consid...Hi Pete<br /><br />Ministry of Defense (MOD) does not consider down-sizing of diesel engine of Soryu. MOD said that they would develop compact, higher power and quite snorkel generation system”[1]. But they did not say that they would down-size the current engine nor that they would develop the smaller engine. The former commander of Fleet Submarine Force also said they would increase intake and exhaust elsewhere (of engine).<br /><br />I compared KAWASAKI 12V25/25SB with MTU20V4000M73 [2-4] which has nearly same power. The power per volume of 12V/25/25SB is considerably-lower than that of 20V4000M3. 12V/25/25SB is already out of date. According to JMSDF, following three factors will be considered: i) higher power by an increase in intake and exhaust, ii) quick response to changing situation, and iii) low rotation of shaft for reduction in vibration. The latter two factors may be satisfied by increase in cylinder number (ex. V16) and/or improvement of turbocharging. The generator may be down-sized. <br /><br />By the way, the latest information on Soryu revealed that number of liquid oxygen tank was one, not two. The tank is horizontally installed on hull. The re-estimated amount of liquid oxygen is 100ton, not changed.<br /><br />[1] http://www.mod.go.jp/j/approach/others/service/kanshi_koritsu/h24/pdf/r-sheetadd/0011.pdf: “FY2011 Administrative Performance Review Sheet of MOD” (Japanese)<br />[2] KAWASAKI 12V25/25 SB(V12 engine, bore/stroke=250/250mm, volume =147L, power=4000ps@1200rpm, power per volume=27ps/L)<br />[3]MTU20V4000 M73 (V20 engine, bore/stroke=170/190mm, volume=86L, power= 4290bhp (4230ps)@1920rpm, power per volume=49ps/L).<br />[4] https://mtu.cwshops.com/media/files_public/uiemfrcem/3237341_MTU_Marine_spec_20V1163M74_1_14.pdf<br /><br />Regards<br />S<br />Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-19245896.post-15579801454574069762015-10-03T20:18:38.061+10:002015-10-03T20:18:38.061+10:00Hi Peter
Not sure if this article from Navy Recog...Hi Peter<br /><br />Not sure if this article from Navy Recognition regarding the different contenders has been mentioned on the blog before.<br />http://www.navyrecognition.com/index.php?option=com_content&task=view&id=2777<br /><br />If it has, just ignore this post. :)<br /><br />Regards,<br />/CAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-19245896.post-88298099990324002422015-10-03T18:19:06.684+10:002015-10-03T18:19:06.684+10:00Hi wispywood2344
Thanks for your comments.
I hav...Hi wispywood2344<br /><br />Thanks for your comments.<br /><br />I have added to the text:<br /><br />- ..."or more advanced Kawasaki diesel"<br /><br />- then later "equipped with newly-developed snorkel-generator system" <br /><br />and <br /><br />"(6) Worked out by wispywood2344 in Comments on October 2, 2015 at 9:39 PM - The 29SS-class must be equipped with "newly-developed" snorkel-generator system, and its diesel engine must not be 12V25/25S variant. Because, TRDI(Technical Research and Development Institute) had concluded that present snorkel-generator system must be outdated in performance in 2020s, and started development of next-generation snorkel-generator system including diesel engine. The main concept is downsizing, increasing power, and reduce noise emission.[see Japanese language PDF]. Note that the first adoption of 12V25/25S series was 28 years ago (lead ship of Harushio-class), and its design is already obsolete. I guess that performance improvement of the diesel engine should be achieved by "expanding boost pressure" and/or "increasing rotating speed"." <br /><br />Regards<br /><br />PetePetehttps://www.blogger.com/profile/02624742078679760819noreply@blogger.comtag:blogger.com,1999:blog-19245896.post-78747325947271271022015-10-02T21:39:40.517+10:002015-10-02T21:39:40.517+10:00Hi Pete.
I think that 29SS-class must be equipped...Hi Pete.<br /><br />I think that 29SS-class must be equipped with "newly-developed" snorkel-generator system, and its diesel engine must not be 12V25/25S variant.<br /><br />Because, TRDI(Technical Research and Development Institute) had concluded that present snorkel-generator system must be outdated in performance in 2020s, and started development of next-generation snorkel-generator system including diesel engine.<br />The main concept is downsizing, increasing power, and reduce noise emission.[1]<br /><br />Note that the first adoption of 12V25/25S series was 28 years ago (lead ship of Harushio-class), and its design is already obsolete.<br /><br />I guess that performance improvement of the diesel engine should be achieved by "expanding boost pressure" and/or "increasing rotating speed". <br /><br />[1] http://www.mod.go.jp/j/approach/others/service/kanshi_koritsu/h24/pdf/r-sheetadd/0011.pdf<br /><br />Regards<br /><br />wispywood2344wispywood2344http://blog.livedoor.jp/wispywood2344/noreply@blogger.comtag:blogger.com,1999:blog-19245896.post-16381016398979464432015-10-02T13:44:45.316+10:002015-10-02T13:44:45.316+10:00Hi S [Oct 2 2015 2:00AM]
Thanks for all these ext...Hi S [Oct 2 2015 2:00AM]<br /><br />Thanks for all these extra comments.<br /><br />1 Change in displacement<br /><br />Is "Surfaced: weight loss{liquid oxygen & container (120t), Stirling AIP (2-3t)} + weight gain {LIBs(380t), longer hull + additional fuel (240t)}=+500t" <br /><br />Do you mean 2,900 tons (current Soryu) + 500 tons = 3,400 tons (surfaced) for 29SS mod-AUS ?<br /><br />"Submerged: increase in water weight corresponding to volume increase with increase in hull length (+4m) = +300t"<br /><br />So I assume you mean 4,200 tons (current Soryu) + 300 tons = 4,500 tons (submerged)<br /><br />2 Speed and range <br /><br />"According to Wikipedia, both surface and snorkel cruising speeds of Collins are 10kt, but these values seem to be introduced as maximum speeds by RAN [1]. I calculated and estimated amount of diesel fuel to achieve wiki-performance of Collins (11,500nm/10kt surfaced, 9,000nm/10kt snorkel) , and concluded that Collins must carry 800-1000ton of diesel fuel to achieve 9,000nm/10kt and that it was impossible. Judging from the projected figure/dimension of Collins and from comparison with Soryu. I think that Collins cruises 9,000nm at ca.6kt snorkel by using ca.300ton of diesel fuel."<br /><br />"29SS mod-AUS may achieve 8000-9000nm/6.5kt snorkel and ca. 3000 nm/4kt submerged. Speed of submarine is affected by drag rather than displacement. In 29SS mod-AUS, as frontal projected area and shape are not changed with slight increase in length (+4m=5%), drag does not become worse meaning negligible loss in performance compared to 29SS."<br /><br />Thanks. I will change the figures accordingly.<br /><br />3 Beam<br /><br />"I think it will be unchanged (9.1m). Pressure shaping of hull steel plate to cylinder is very difficult process, so lengthening hull is much easier than broadening beam to increase submarine volume."<br /><br />Thanks. I will return beam back to 9.1m.<br /><br />4 Improvement in diesel engine for rapid charge of LIBs<br /><br />"Enhancement of diesel generation will be achieved by simple capacity increase (increase in bore and stroke) in cylinder volume, not by increase in numbers of diesel engine or cylinder. Increase in numbers of diesel engine requires change of arrangement of diesel engine room. V12 engine (12V25/25SB) is best cylinder configuration with ideal balance and least vibration.<br />The capacity increase in cylinder is dominated by snorkel capacity which may increase to certain extent which is limited by the unchanged dimension and shape of the mast. JMSDF may make an increase in diameter of snorkel and filter efficiency up to 20-25%. I think new V12 engine can improve in performance of 50-100% (12,000-16,000PS) which brings increase in snorkel speed (15-25%)."<br /><br />Thanks. I will return to 2 12V25/25SB diesels and add you explanation.<br /><br />5 Number of Crew<br /><br />"JMSDF adopts 3 working shift system for submarine operation except cooks with 2 working shift and RAN adopts 2 working shift system. In efficient 29SS without AIP, they can reduce at least 6 crews resulting in total 59 crews. In case of 29 mod-SS, total crew may be 40."<br /><br />Thanks. I will change down to 40 and add your comments.<br /><br />6 R&D status of new hull steel<br /><br />"They may have already started R&D secretly, I just imagine." Quite possibly DSTO, some JMD body and maybe US are working on it. <br /><br />[1] "http://www.navy.gov.au/hmas-collins" is a good reference. Of major importance is that a submarine moving on the surface is very unlikely (in transit and certainly in operational areas). Dived and snorting speed and range is much more relevant.<br /><br />Regards<br /><br />PetePetehttps://www.blogger.com/profile/02624742078679760819noreply@blogger.comtag:blogger.com,1999:blog-19245896.post-57340646152787630182015-10-02T09:27:12.016+10:002015-10-02T09:27:12.016+10:00Hi Parikrama [re commentg you provided October 1-2...Hi Parikrama [re commentg you provided October 1-2 2015]<br /><br />Thankyou for your comments on the US and France helping India with its SSN program.<br /><br />As I have already done an article on that subject "US and France in talks with India to Assist India's Nuclear Submarine Program" of September 29, 2015 at http://gentleseas.blogspot.com.au/2015/09/us-and-france-in-talks-with-india-to.html<br /><br />I have moved your comment to Comments under http://gentleseas.blogspot.com.au/2015/09/us-and-france-in-talks-with-india-to.html - where I shall respond more fully to you.<br /><br />Regards<br /><br />Pete Petehttps://www.blogger.com/profile/02624742078679760819noreply@blogger.comtag:blogger.com,1999:blog-19245896.post-78038057380141542092015-10-02T02:00:01.185+10:002015-10-02T02:00:01.185+10:00Hi Pete
I show additional comment on 29SS mod-AUS...Hi Pete<br /><br />I show additional comment on 29SS mod-AUS (FY 2017 submarine modified for Australia)<br /><br />1 Change in displacement<br /><br />Surfaced: weight loss{liquid oxygen & container (120t), Stirling AIP (2-3t)} + weight gain {LIBs(380t), longer hull + additional fuel (240t)}=+500t<br /><br />Submerged: increase in water weight corresponding to volume increase with increase in hull length (+4m) = +300t <br /><br />2 Speed and range <br /><br />According to Wikipedia, both surface and snorkel cruising speeds of Collins are 10kt, but these values seem to be introduced as maximum speeds by RAN [1]. I calculated and estimated amount of diesel fuel to achieve wiki-performance of Collins (11,500nm/10kt surfaced, 9,000nm/10kt snorkel) , and concluded that Collins must carry 800-1000ton of diesel fuel to achieve 9,000nm/10kt and that it was impossible. Judging from the projected figure/dimension of Collins and from comparison with Soryu. I think that Collins cruises 9,000nm at ca.6kt snorkel by using ca.300ton of diesel fuel.<br /><br />29SS mod-AUS may achieve 8000-9000nm/6.5kt snorkel and ca. 3000 nm/4kt submerged. Speed of submarine is affected by drag rather than displacement. In 29SS mod-AUS, as frontal projected area and shape are not changed with slight increase in length (+4m=5%), drag does not become worse meaning negligible loss in performance compared to 29SS.<br /><br />3 Beam<br /><br />I think it will be unchanged (9.1m). Pressure shaping of hull steel plate to cylinder is very difficult process, so lengthening hull is much easier than broadening beam to increase submarine volume.<br /><br />4 Improvement in diesel engine for rapid charge of LIBs<br /><br />Enhancement of diesel generation will be achieved by simple capacity increase (increase in bore and stroke) in cylinder volume, not by increase in numbers of diesel engine or cylinder. Increase in numbers of diesel engine requires change of arrangement of diesel engine room. V12 engine (12V25/25SB) is best cylinder configuration with ideal balance and least vibration.<br /><br />The capacity increase in cylinder is dominated by snorkel capacity which may increase to certain extent which is limited by the unchanged dimension and shape of the mast. JMSDF may make an increase in diameter of snorkel and filter efficiency up to 20-25%. I think new V12 engine can improve in performance of 50-100% (12,000-16,000PS) which brings increase in snorkel speed (15-25%).<br /><br />5 Number of Crew<br /><br />JMSDF adopts 3 working shift system for submarine operation except cooks with 2 working shift and RAN adopts 2 working shift system. In efficient 29SS without AIP, they can reduce at least 6 crews resulting in total 59 crews. In case of 29 mod-SS, total crew may be 40.<br /><br />6 R&D status of new hull steel<br /><br />They may have already started R&D secretly, I just imagine. <br /><br />[1] http://www.navy.gov.au/hmas-collins<br /><br />Regards<br />S<br />Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-19245896.post-6252960416079601672015-10-02T01:39:15.650+10:002015-10-02T01:39:15.650+10:00Hi Pete,
Thanks for this detailed & well info...Hi Pete,<br /><br />Thanks for this detailed & well informed article.<br /><br />From what you are suggesting its look like the replacement for the Collins-Class SSK could well turned to be a beast of a sub & more importantly one of the best non-nuclear sub.(considering where this sub has to operate it will surely need all those said capabilities)<br /><br />Hoping for the best.<br /><br />Regards<br /><br />BiswajitAnonymoushttps://www.blogger.com/profile/15778141539525650990noreply@blogger.com