PLAN submarines Thread II

[crobato]

The sequel.

Anyway to start with, I have some thoughts.

1. Some thought about the stationing of subs in Sanya, Hainan. Subs tend to be designed by countries that are in colder climates, hence colder waters. Thus how they deal with cooling, to their sonar issues, have a tendency to be biased towards cold waters. When it comes to warm waters, or tropical conditions, warm waters can expose a new bag of issues to submarines whose design did not foresee warm water effects.

In China's case, their SSKs, the Song and the Yuan, appeared designed and built by shipyards that are more to the south or middle of China, and therefore faces a more moderate to semi-tropical environment. These subs probably have greater consideration to tropical climates, hence they were the first to be stationed to the south.

But Huludao is a different case being far up north. This is a place that is cold enough to have snowstorms and ice forming in the water. As China's nuclear subs are born there, their cooling requirements among other things may have been oriented at first to that region. Hence the stationing of the Hans and Xia to the North Sea Fleet, and so was the early 093 and 094.

But the appearance of the improved Han (091G), the 093 and 094 as far south as Sanya, Hainan indicates tropicalization measures and testing are being imposed on the subs, to turn them from "cold water" to "all water" subs.

2. The second issue that I like to raise, and its been in my mind for some time now, is the so called "smooth look" that has been with some European subs, particularly German and Swedish. This look is one with straight upper deck and angled upper sides of the body. The British have also decided to run this look too, and lately the Japanese are converts to this approach, based on the look of the Soryu class sub.

Is this design really better? Some of the most quietest subs in the world actually never chose to have this approach, and they include the Seawolf, Virginia and the French Scorpene class. These last three subs still favor the rounded body look that was pioneered long ago by the Albacore.

So what is the theory behind this angled smooth look that the Germans and Swedish came up with? If I think about it, its not really hydrodynamics. Submarine hydrodynamic design reached a perfect stage when the Albacore came out back in the fifties, and that sub actually has a speed record faster than nuclear subs even though it only had diesels. The optimal design for speed, as that sub showed, is one based on the fish it was named for.

The straight upper deck and angled sides of the German and Swedish subs in a sense is not actually hydrodynamic but contrary to it, its not really streamlined. So I have another theory as the angled sides and straight look reminded me of something else, something you see in the latest fighters and surface ships---stealth.

Having straight lines and angled sides are meant to minimize reflection from going into different directions. Instead, these reflections are aimed into as few directions as possible. The less directions the reflections are scattered, the better.

If this principle can work with radar, it can work on sonar.

This does not mean the sub is going to be quiet. This design has nothing to do with quietness or passive stealth. Rather, it is meant to counter active sonar, reducing the range of detection and echoes from a hunting ping. Active sonar is actually the last and best resort to defeat a quiet SSK, because no matter how quiet you are, you won't escape your own reflections. Usually, subs have adopted using all sorts of coatings and tiles to help counter active sonar. However, we all know even from aircraft to ships, that designing to counter reflections from the start, is a superior method over applied methods such as coatings like RAM and so on.

The con to this is that the sub may not be as hydrodynamically efficient or even as quiet once the speed picks up. This however can be empirically adjusted and fine tuned through wind tunnel and water tank testing. For SSKs running at slow speeds it probably is a better judgement call, to have more active sonar stealth over hydrodynamic efficiency at higher speeds.

The US, Russian, French and it seems even to the Chinese, that their emphasis is speed and to reduce flow noise for burst, cruise or transit speeds, and for tactical speeds. It may seem counter intuitive to some, but you can actually reduce drag and noise through a more "disturbed" rather than a clean look towards the middle to end of the body. This is similar to the nipples in a golf ball. One way to achieve this is to strategically design and position your limber holes and other small protrusions, and you can empirically determine this by wind tunnel and water tank testing. This can explain the look and adjustments I've seen with many subs on their limber hole patterns.

My theory goes, that the "rounded" subs are probably hydrodynamically quieter than the "angled" subs at speed, not counting other noise producing factors like powerplant, but once the subs go actively pinging, the rounded subs would be in a disadvantage over the angled subs.

The question now remains what is the trend for future PLAN submarines? Will they still go after hydrodynamic efficiency as the Yuan and Shangs still do? Or like those certain models show, a shift towards being able to counter active sonar as well?

3. The third thing I like to bring out are the Red and Blue Flag exercises. Certainly the J-10 vs. J-11 encounters are probably well known among the Chinese watchers now. Through these exercises, you can actually shape policy.

But does the PLAN's ship and sub policy changed by similar exercises? Of course we will never know the results of sub vs. sub encounters within the PLAN, e.g. Yuan vs. Shang, Song vs. Kilo, PLAN SSKs vs. PLAN SSNs, etc,. Hypothetically, if you are in the PLAN's place, and you conduct such exercises, will the results of these exercises help shape future policy and purchasing plans? One thing I noticed that in China, you don't stick completely to the long term plans but make adjustments along the way, and must be flexible even to change the long term plans if they were shown to be wrong or obsolete. Its not hard to imagine that Shangs and Improved Hans working as Blue forces, with Jins or the improved Xia thrown in as targets or hunters, against Songs, Yuans, Kilos and Mings acting as Red forces.

[jackbh]

I have never heard and imagined such thing as sub designed in cold water is not adaptable in tropical water. This is for me like saying if you designed a car in Sweden where it's cold then the car will not run in Hawaii where it's warm. This is just hard to imagine.

Look at all the volvos and Saabs running around in hot and warm weather.

[crobato]

Originally Posted by jackbh

I have never heard and imagined such thing as sub designed in cold water is not adaptable in tropical water. This is for me like saying if you designed a car in Sweden where it's cold then the car will not run in Hawaii where it's warm. This is just hard to imagine.

Look at all the volvos and Saabs running around in hot and warm weather.

You have to do modifications to adapt to warm water, particularly in the way you provide cooling for the engine and the crew. As a matter of fact, European cars for a while had inadequate air conditioning---they were never known for the quality of their climate control, as well as the propensity to overheat in the traffic jam of a city in the tropical regions. That was a long ago then, today, all cars are being tested in every possible environment. That's one reason why BMW for example, sends prototypes to Death Valley in the USA.

[crobato]

I'm still trying to verify if this pic is Chinese or not.

[Norfolk]

WOW, crobato. Great pic, where did you find this? Could this be of the new sub base tunnelled into Hainan Island?

[beijingcar]

that picture is Chinese allright, I saw it about 3 years ago and saved on my hard-drive on my old computer, then the HD crashed, picture was lost. As I remember, it was the only official release of the underground picture of the PLAN TsingTao Sub base. I believe the picture was taken maybe 10 years ago( or could be even older), as the Han 091 was not yet being modernized(for the second and last time). Maybe #403?

[maozedong]

yes,I saw it in chinese sit last year,I believe that this is an old Han-class submarines, can see the red banners affixed to the sail,
It is evident that the Chinese characteristics, I have not Favourites it because I like new things. I have read some magazines, Huludao has such base tunnel.
I agree with Beijingcar,about 10 year ago,China's official release of some old photographs, read to the Chinese people manufacture of a nuclear submarine of arduous process.

[Schumacher]

Looks like the mainstream press finally caught on to this pic of a new Yuan, the HK newspaper below is quoting French report.
As usual, posters on Sinodefence got there earlier. I wonder if the press will acknowledge if they really got it from our site here.

http://www.takungpao.com/news/08/01/28/ZM-857242.htm

[crobato]

This is the French article, that was translated to Chinese, then translated to English using Google, so it's not a good translation at this point, but you can still pick out a thing here and there. Note the new Yuan might be called 039B. The article is also saying the same thing I said in the other thread, that the Song and the Yuans are double hulled, and that the two subs may be sharing the same inner pressure hull, which contains the core of the submarine, crew, controls, engine and the like, differing in the outer thin hydrodynamic hull.



France "submarine portal," said, this is not very clear photographed is not yet launched a new version of the 039 submarine

Global Network: France "submarine portal" recently published article, saying through an appearance comparison found the latest model Chinese submarine.

The article said that a new Chinese submarine photos recently appeared on the Internet, the photos are not located in close-range focus has been recognized as yuan level (A-039) submarines, but slightly distant floating dock on the submarine. It is neither the 039 nor the 039 Type A, in other words, this is not very clear photographed is not yet launched a new version of the 039 submarines.

This submarine and the two former known version of the submarine conning tower is the main difference between the horizontal position. China seems to be drawing people to do some modifications to the installation of some new things. In fact, the top shell to amend section than to increase much easier. This approach is used in the 093 submarine-based ballistic missile submarine construction of the 094 projects, 094 in the 093 is on the increase for a cabin with no re-design hull shape. Found a photo of the Russian submarine experts made the following comments:

It seems that Shell made changes in fluid mechanics, slightly widened and lengthened shell, which may be altered to accommodate the new power system. Perhaps China in the Yuan class in the installation of the first set of Air independent propulsion (AIP) system, there are some problems at the beginning, the concept of change may reflect an evolution. If they changed the dynamic system, it may be in the boat in the shell have to do some modifications, which means that the submarine may have a new design. Song and Yuan-class submarines are in the 039, because they are within the same shell.

China submarine with dual-shell structure, and Song (039) and the Yuan class (A-039) within the shell is very similar to, if there is no shipboard equipment, and then only through the shell shape to distinguish between them. In fact, the Song (039) and meta-level (039-A) and traditional submarines, the main difference lies in the case of underwater navigation resistance decreased slightly. In the use of new technologies need to install, it can only change the shell structure, and ensure that some of the inner shell is no longer reliable design changes.

In the absence of multi-angle photos circumstances, it is difficult to determine the submarine the size and power. "Defence discussions" web site professionals may believe that the new submarine in the Air independent propulsion (AIP) systems have some improvements. He stressed that the change in the top of the hull of the ship than to change the balance of more meaningful.

This picture is not in the submarine B-039, is still too early to say, but is set off in Wuhan is the construction of the 039 submarine like a new version.

[evereachyu]

Originally Posted by crobato

I'm still trying to verify if this pic is Chinese or not.

This is an aged photo. It was posted on one of the Chinese magezines, might be 《舰船知识》。

[tphuang]

a little bit on the AIP engine installed on Yuan

国产AIP系统被官方媒体披露！
原载《科技日报》

“心”动力成就新梦想
中国船舶重工集团七一一研究所特种发动机应用出新果

福州红庙岭垃圾填埋场从今年起，每年都将会发一笔“意外”之财。当然，并不真的是天上掉馅饼，而是因为历时 一年有余，其垃圾填埋场封场覆盖及填埋气发电项目终于竣工投产，以后每年可向华东电网输送1200万千瓦时 的电能。
　　这个项目的核心———特种发动机技术的承建者，则是有30年特种发动机研究历史的———中国船舶重工集 团七一一研究所的下属单位上海齐耀动力技术有限公司。

　　特种发动机，是一种由外部供热使气体在不同温度下做周期性压缩和膨胀的闭式循环往复式发动机，七一一研 究所研制的这种发动机，是一种具有国际水准的科研新成果，有分别带动20千瓦和100千瓦发电机的不同机型 ，既可以使用天然气、柴油、太阳能，又可使用其它固体燃料作动力进行发电，而排放的污染气体比目前市面上的 其它发动机都要少，已达到欧洲排放标准，在民用和军用领域均可大规模应用。

　　目前，这一发动机已成功应用于我海军新型AIP潜艇上。由于它不依靠空气推进的动力装置，大幅降低了潜 艇噪声，能使潜艇在水下长期航行，增强了潜艇的隐蔽性，进而大大提升了我国海军作战实力。

　　此前这种船用发动机技术只有极少数国家掌控，如今完全实现了自主研发，被国内外誉为一颗强劲的“中国心 ”。

　　特种发动机的研究，凝注了中国船舶重工集团公司七一一研究所研发人员数十年的心血。1975年，中国舰 船研究院第七一一研究所成立特种发动机研究室， 1996年6月，成立特种发动机工程研究中心。经过“八五”、“九五”的研究，相继突破12项关键技术。1 998年，他们研制成功了拥有完全自主知识产权的我国第一台特种发动机原理样机之后，他们又研制成功了工程 样机，总体水平达到了国际先进水平，部分技术处于国际领先地位。

　　在特种发动机的研究过程中，七一一研究所以此为契机，培养了一大批技术骨干力量。从主持该项目之初，课 题组只有10多人，而现在发展到100多人。涌现了上海市劳动模范、上海市青年科技英才等先进人物，也正是 这支团队，多次被评为解放军总装备部“预研先进集体”，两次被授予“上海市劳动模范集体”称号 。

　　为了更好地推动特种发动机的应用，七一一所的特种发动机工程研究中心整体转制成立上海齐耀动力技术有限 公司，并建成了位于上海浦东张江高科技园区研究和试验基地。而前不久完工的福州红庙岭垃圾填埋场封场覆盖及 填埋气发电项目，使这一技术在民用领域方面的应用更加成熟。

basically said that they got a prototype as early as 1998 and the AIP engines come in the form of 20 and 100 kw. Of note, the stirling engines used on Gotland generate 75 kw each. So, 2 100 kw AIP engine on the larger Yuan would make sense.

[kickars]

Originally Posted by jackbh

Look at this bad boy.

http://x.bbs.sina.com.cn/forum/pic/47471c530104vdnt

http://x.bbs.sina.com.cn/forum/pic/47471c530104vdnv

http://x.bbs.sina.com.cn/forum/pic/47471c530104vdnx

http://x.bbs.sina.com.cn/forum/pic/47471c530104vdnz

The supposed 095, this is nuts.

cannot see the pics

[jackbh]

When I click on those links, I can see the pictures.

And I know those are just some CGs, but it could be close to the real thing.

[maozedong]

the last one in the link is real.
however they are good pics, I like.

[kw64]

Originally Posted by maozedong

the last one in the link is real.
however they are good pics, I like.

No way they're real, look like amature CG works to me. But on a side note, I heard from Chinese news that they've developed working AIP systems and have installed them in their subs already. Is it true? I thought they had some problems with the whole AIP thing.