Type 097 and 098 submarines
The Chinese Navy had the first generation of 091 and 092 type nuclear submarines, the second generation of 093 and 094 nuclear submarines, and the third generation of Type 095 and 096 nuclear submarines. IN each case, the odd numbered boats were attack submarines, that used systems also used on the larger even-numbered ballistic missile submarine. The Type 097 and 098 submarines do not appear to represent real programs.
Chinese media reported in 2015 that "Vice Governor of Liaoning Province Tan Zhaun recently disclosed in public, the PLA Navy fourth generation nuclear submarine has been developed. Hong Kong "Mirror" magazine recently reported that the mainland developed the fourth generation of submarines for many years, and its third generation nuclear submarine 095/096 type has not yet publicly appeared, nor was the US side to detect.
"Vice Governor of Liaoning Province Tan Zuojun revealed that the fourth generation of nuclear submarines have been developed to complete the news, immediately caused by foreign media and military experts in a wide range of speculation, some experts believe that the message credible. Hong Kong military analysts believe that the fourth generation of nuclear submarines should be inferred 097 and 098 type.
"According to Liang Gangliang, a military expert from Hong Kong, the People's Liberation Army (PLA) has developed a fourth-generation nuclear submarine since 2000. It is said that the design of this submarine is revolutionary, with unprecedented magnetic fluid propulsion, without propeller."
Chinese internet artwork depicts such a submarine, with a length of 167 meters [543 feet], a beamof 15 meters [seems a bit wide], a surfaced displacement of 17,050 tons and a submerged displacement of 20,050 tons. The boat is claimed to have a test depth of 500 meters, with a crew of 140. It is reported to carry a total of 24 "JL-4" SLBMs with a range of 15,000 kilometers, probably a further development of the JL-3.
Tom Clancy’s novel "The Hunt for Red October", published in 1984, told the story of a submarine of the Soviet navy, under the old communist regime, that tried to defect to the West. Meanwhile, US government officials try o determine if his defection is for real or a ploy. The 1990 movie starred Alec Baldwin as a US intelligence agent tracking the maiden voyage of the new, secret Soviet submarine Red October. Sean Connery was the Soviet sub commander, who was up to something. The Soviets had created a new nuclear submarine that can run virtually silent due to a revolutionary magnetohydrodynamic propulsion system. With such a device, they can position themselves on the outskirts of any coastal city and launch their missles and not give their target any warning. Navy involvement in the filming resulted in “Hunt for Red October” being as realistic as possible. And by working alongside Navy people, the actors were able to be very convincing sailors.
The United States had considered MHD for ship propulsion since 1960; here compactness and the absence of rotating machinery were felt to be important from a viewpoint of reducing noise, especially important in submarine propulsion. The Soviet Union has been a major source of MHD research and there is evidence of a large R&D effort.
The feasibility of MHD propulsion was first demonstrated by Stewart Way who published a very complete and mathematically rigorous analysis of an external duct, DC propulsion system. Way constructed a small 3-meter long, 900 lb. displacement submarine model (EMS-I) in 1966. Using conventional magnet coils and battery power, the EMS-I model achieved almost 2 knots with a very weak (0.02 T) magnetic field.
In 1989, a paper study by Adalbert A. Bednarczyk set design criteria at a 100 MWt nuclear reactor power upper limit and a requirement of 30 knots for the top speed. This required advanced reactor plant and advanced energy conversion system. The selection of High Temperature Gas Reactor (HTGR) and Liquid-Metal Fast Breeder Reactor (LMFBR) was based on the combined merits of safety, environmental impact, high source temperature and maximum volume power density (KW/L). With the reactor outlet temperatures of 2000 K direct cycle energy conversion systems gave the best results in terms of thermal efficiency and propulsion plant power density. Two energy conversion systems selected were closed-cycle gas turbine geared to a superconducting generator, and closed-cycle liquid-metal MHD generator. Based on submarine reliability and safety the option of using an intermediate heat exchanger was also considered.
Recognizing the potential of MHD for underwater propulsion of Naval vessels, the Office of Naval Research organized a workshop in October 1988 in Washington, DC. Experts from all over the country were invited for the two-day brainstorming sessions to explore the underlying issues of MHD propulsion. Research programs on MHD propulsion were initiated by ONR and DARPA to gain understanding of the fundamental mechanisms involved, and to demonstrate its feasibility. Some important issues were identified, solutions of which are of great significance for a successful MHD underwater thruster development.
In a so called magnetic hydrodynamic propulsion an electric as well as a magnetic field are superimposed upon a medium which contains movable charge carriers. As a consequence of the action of the electric field, the charge carriers begin to move and then in consequence of this motion of the charge carriers in the magnetic field the so called Lorentz force is exerted on the charge carriers, this force being given by the cross product of the magnetic field and velocity vectors.
In the application of magnetic hydrodynamic propulsion to water vehicles , a pipe is surrounded by two superconducting saddle coils which are arranged symmetrically about the pipe axis. The saddle coils produce, in this manner, a magnetic field whose direction is perpendicular to the pipe axis. In the pipe, two condensor like plate electrodes are arranged in an axial direction so that the magnetic field produced by these plate electrodes likewise runs perpendicular to the direction of the axis and also perpendicular to the direction of the magnetic field.
This has the consequence that the free charge carriers of the surrounding water which are located in the pipe, principally salt water ions, are acted on by a Lorentz force which runs in the axial direction of the pipe. In this way, the arrangement which is known in the art produces a recoil force which stems from the charge carriers which are moving axially in the pipe. For the propulsion of a water vehicle, the saddle coils produce a magnetic field strength of two Tesla using a current of 2,000 Amperes which is supposed to lead to a recoil force of 8 KN.
The underlying physical principals necessary for understanding this type of magnetic hydrodynamic propulsion are described in the text book of Becker/Sauter "Theorie der Elektrizitat", 19. Edition, 1969, Vol. I, Pages 255 to 266, as well as in the text book of Pohl "Einfuhrung in die Physik", 20. Edition, 1967, Vol II, "Elektrizitatslehre" pages 98 through 104.
However, the apparatus and procedure have the disadvantage that the efficiency is relatively low and the construction of the coil is relatively complicated. A further disadvantage of the configuration known in the art is that, as a result of the use of saddle coils, a very large stray field is produced so that vehicles which are configured with the propulsion apparatus known in the art are easily detected by means of magnetic detection methods. Furthermore equipment which is located on board the water vehicle, in particular electronic equipment, is perturbed by the stray field of the magnet coil.
Solenoid coils have, in contrast to saddle coils, a significantly larger efficiency since the magnetic field produced by the solenoid coils is completely enclosed by the coil itself and the stray field of such a coil is very small. Furthermore a solenoid coil is, by way of example, substantially simpler to construct than a pair of saddle coils whereby the individual coil shapes and thereby that of the support structure as well require great effort. It is particularly advantageous that the hydrodynamic propulsion element with the directing elements is arranged within the solenoid coil. This configuration is substantially more compact than the conventional configuration wherein the propulsion motor and the propeller are arranged in a row, one behind the other.
The procedure and the apparatus has the advantage that the propulsion unit does not, in any way, need moving elements and, therefore, practically no propulsion noise is produced. For this reason, this type of configuration is well suited for military applications, in particular, for the propulsion of submarines.
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