JPS6042694A - Power device for underwater travelling body - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a power system for an underwater vehicle, particularly an unmanned underwater vehicle that travels under the sea or on the ocean floor in the deep sea using its own power source to conduct investigations, work, etc.

In recent years, offshore oil exploration work has gradually reached deep seabeds, and simple tasks such as observation and maintenance are now being carried out by unmanned submersible vehicles for the safety of human life. These unmanned underwater vehicles have been improved year by year, and high-performance, deep-dive models are being developed one after another and are appearing on the market, but conventional ones require a complete set of tethers (with a tether) in terms of power supply and information transmission. (rope type), directly from the mother ship on the water.
Alternatively, it was connected to a launcher on the ocean floor that was connected to the mother ship with an umbilical cable (umbilical cord, lifeline), and power for propulsion, work, information equipment, etc. was supplied via the tether.

However, the underwater vehicle with a set of tethers has the following drawbacks, and it cannot be said that it has sufficient adaptability for underwater work. That is, (a) Because the tether becomes tangled, it is impossible to enter structures such as submarine oil well jackets, and the travel route and radius of movement are restricted.

(b) The underwater resistance of the tether impedes free movement, especially when there is a current.

In addition, even if the depth is such that a manned underwater vehicle or Daiper can dive, for example, when blowing off oil inside a structure under tidal currents or investigating a disaster, the Diaper or manned underwater vehicle cannot approach due to the danger. In addition, underwater vehicles with tethers cannot enter because they may become entangled with structures, and detailed operations such as operating blowout preventers are difficult due to the large resistance of the tether due to the tidal currents.

For the above reasons, there is a strong demand for an autonomous recognition/working underwater vehicle without a tether, and its immediate development is desired.

One of the technical challenges to achieve this is to provide a power unit that is built into the underwater vehicle and can be operated unmanned.

By the way, in order to investigate the topography and geology of the seabed for the purpose of seabed oil exploration, there is a small underwater vehicle that is launched from a mother ship at sea, travels a predetermined course, and then returns to the mother ship. If you return to the mother ship every time,
It uses a storage battery as a power source and is easy to charge or replace.

However, in the case of underwater vehicles that conduct research and work on the deep seabed, launching from a submerged mother ship and returning to the mother ship each time involves a large loss of time and power, and in the case of underwater vehicles that conduct research and work on the deep seabed, In many cases, it is difficult to surface to the mother ship due to self-defense. Therefore, underwater vehicles operating on the deep seabed are connected to a launcher on the seabed that is connected to the mother ship with an umbilical cable.
Start from and return. Therefore, it is not possible to charge or replace batteries on the mother ship, and it is necessary to build a power device into the underwater vehicle that does not require refueling or charging for a long period of time, or to use batteries as a power source. It is necessary to have a device that can safely and reliably charge the battery inside the carry-on launcher.

An object of the present invention is to provide a power device for an underwater vehicle that is built into the underwater vehicle and does not require charging or refueling.

The use of nuclear power and radioactive isotopes can be considered as power plants that do not require refueling. Nuclear power is already being used for propulsion in military submarines. In this case, a driving medium heated by the heat of the nuclear reactor drives a turbine to turn a generator, and the resulting electric power drives a propulsion motor.

In nuclear submarines, it is relatively easy to provide space within the pressure hull to mount turbines and generators. Furthermore, it is difficult to completely unattend control and maintenance of the turbine. Therefore, it is difficult to use a power source that uses nuclear power to drive a power generation turbine as a power source for an unmanned vehicle for investigating or working on the deep seabed.

Furthermore, power generation devices that utilize the decay heat of radioactive isotopes are used as power sources for artificial satellites and the like.

Thermoelectric power generation technology, a technology that converts heat into electricity by utilizing the thermal difference between a high-temperature heat source and a low-temperature heat source, has recently been actively researched and developed at home and abroad.

A thermoelectric element is a semiconductor with excellent thermoelectric performance (the ability to convert heat into electricity), and by heating one side and cooling the other side, it generates an electric current depending on the temperature difference between the two sides. Electricity is generated.

The present invention focuses on the above-mentioned characteristics of thermoelectric elements, and uses nuclear or radioactive isotopes as a high-temperature heat source that heats one side of the thermoelectric element without requiring long-term refueling and which can provide a large heat output with a small amount of fuel. The power source of the underwater vehicle is a thermoelectric generator that uses low-temperature seawater from the deep sea floor as a low-temperature heat source to cool the other side of the thermoelectric element.

Hereinafter, the present invention will be explained in detail based on embodiments shown in the drawings.

Now, there are two types of thermoelectric elements: N type and P type.
The relationship between the heating and cooling surfaces and the direction of the electromotive force is reversed depending on the mold. Therefore, as shown in FIG. 1, the P-type thermoelectric element P1. P2. . . . and an N-type thermoelectric element N1. N2. . . . are arranged alternately, and each two adjacent thermoelectric elements are arranged at Pl and N1°P2 and N on the upper side.
2. ......, N1 and P2 on the lower side.・・・・・・
In this way, the metal electrode pieces 2 are connected in a staggered manner, and one heats the electrode piece on one side and cools the electrode piece on the other side.
In other words, P-type and N-type thermoelectric elements are electrically connected in series,
Thermally, if they are connected in parallel to form a single module, and one side is heated and the other side is cooled to create a temperature difference between the two sides, the temperature difference between the terminals connected to the thermoelectric elements at both ends An electromotive force is generated.

Examples of thermoelectric modules are shown in Figure 2 (a) l (b) l (e
)l Shown in (d).

(a) shows the top surface of the module, (b) shows the front surface, (C) shows the bottom surface, and (d) shows the side surface. A suitable number of P-type and N-type elements 1 are arranged in two rows as shown in the figure, with P-type and N-type elements alternately arranged in each row and P-type and N-type elements lined up in two transverse directions. The electrode pieces 2 made of a copper plate are used to connect two P type electrodes and two N type electrodes arranged in the transverse direction on the upper surface as shown in FIG. 2(a).
On the bottom surface, as shown in Figure 2 (C), two P type and N type pieces that are adjacent to each other in the longitudinal direction of the module are connected alternately like brickwork, and thermoelectric elements without electrode pieces 2 are attached to the bottom surface of both ends. A terminal plate 6 similar to the electrode plate 2 is connected to the lower surface of the electrode plate 2.

The electrode plate 2 and the terminal plate 3 serve as both electrical conductors and heat transfer surfaces.

As shown in FIG. 3, the thermoelectric module 4 includes a heat transfer tube 5 with a rectangular cross section, in which a low temperature heat medium and a high temperature heat medium H flow, respectively.
6, the heat exchanger tube 5, so that its surface is in close contact with the electrode piece 2,
6 and thermoelectric modules 4 are stacked alternately to form a thermoelectric power generation device.

In the thermoelectric power generation device of the present invention, as shown in the system diagram in FIG. 4, low-temperature seawater 9 is introduced from outside the traveling body 8 by a pump 7 into the low-temperature heat exchanger tube 5 that contacts one side of the module 4, and the tube wall is heated. It exchanges heat with the module 4 through it, is heated, and is discharged outside the vehicle again.

On the other hand, a high-temperature heat transfer medium heated by a nuclear reactor or radioactive isotope 11 is circulated by a pump 10 through a high-temperature heat transfer tube B that contacts the other surface of the module 4, and heat is transferred to the module 4 via the tube wall by +4 Ru.

Nuclear fuel or radioactive isotopes produce a large amount of energy with a small mass and have a very long lifespan.

In addition, seawater, which is a low heat source, has a low temperature on the deep sea floor, which can improve power generation efficiency. Also, since there are almost no mechanically moving parts like turbines and generators (high temperatures,
Low-temperature medium circulation pump only) It can be easily operated even when unattended, and since there are almost no parts that can break down, it can be maintenance-free.

As described above, according to the present invention, there is no need for long-term replenishment of fuel, battery charging, or replacement, automatic control is easy, and maintenance-free power can be obtained, making it effective as a power source for underwater vehicles without tethers. It can be used for.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram explaining the principle of thermoelectric power generation, and Figures 2 (a), (b), (e), and (d) are top, front, and bottom views of an example of a thermoelectric module, respectively. 3 is a side view, and FIG. 3 is a perspective view showing a part of the thermoelectric power generation device constituted by the above-mentioned module and high temperature and low temperature heat exchanger tubes. FIG. 4 is a system diagram of an embodiment of the present invention. 1... Thermoelectric element 4... Thermoelectric module 5... Low temperature heat exchanger tube 6... High temperature heat exchanger tube 8... Underwater traveling body 9
... Seawater 11 ... Nuclear reactor or radioactive isotope

Claims (2)

[Claims] (1) One side of the thermoelectric element is heated using a heat medium heated by heat generated from a nuclear reactor mounted on an underwater vehicle as a high-temperature heat source, and the seawater around the underwater vehicle is used as a low-temperature heat source to perform the above-mentioned method. 1. A power device for an underwater vehicle, characterized in that a thermoelectric generator is used as a power source to generate an electromotive force by cooling the other side of a thermoelectric element. (2) One side of the thermoelectric element is heated using a heat medium heated by heat generated from a radioactive isotope mounted on the underwater vehicle as a high-temperature heat source, and the seawater around the underwater vehicle is used as a low-temperature heat source. A power device for an underwater vehicle, characterized in that the power source is a thermoelectric power generation device that generates an electromotive force by cooling the other side of a thermoelectric element.