JPS61205596A - Vessel of shielded underwater propeller noise - Google Patents

Abstract

PURPOSE:To shield noise to be radiated from propeller into the water by applying acoustic material onto the inner face of horizontal propeller noise shielding member and the bottom face near the front opening. CONSTITUTION:Under-water propeller noise shielding member 6 is provided while covering the opposite sidefaces and the underface of propeller 2 and thrust shaft 4 where said member 6 and a bottom outerboard 11b at the stern will form a tubular member 13 and an acoustic material 10 is applied onto the inner face of said tubular member 13. while an acoustic material 10' is applied onto the bottom outerboard 11b at the stern which will face against the front opening 14 of said member 6 or the bottom face of hull 1 to which the underwater noise 9 from the propeller 3 will be incident directly.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a ship capable of shielding noise radiated into the water from a propeller.

[Conventional technology]

Conventionally, in ships, etc., as shown in Figure 9,
Various acoustic sensors for undersea exploration and other purposes*
However, since it is necessary to operate the various propulsion equipment of ship a, amplitude noise is generated when the equipment is operated, and this is radiated into the ocean (underwater), causing the acoustic sensors g and h to be
performance has been hindered.

In particular, the propeller C is indispensable for propulsion of the ship a, and since it rotates at high speed underwater, it accounts for most of the noise radiated into the water of the ship a.
Although this is considered to be the main cause of inhibiting the performance of acoustic sensors GVH, it has the drawback that no effective countermeasures can be taken.

In addition, in Fig. 9, the symbol s is a skeg, d is a shaft bracket that supports the propeller C and the propulsion shaft e, e is the propulsion shaft, and f
is the rudder, and i is the noise generated by the propeller rotation and radiatively propagated into the water.

[Problem that the invention seeks to solve]

However, in ships equipped with such conventional acoustic sensors, the propeller underwater radiation noise i is detected by the acoustic sensor g.
There is a problem that the performance of TLL is inhibited.

In addition, as a countermeasure, as shown in Fig. 10, it has been proposed to shield only the propeller rotating part with a shielding member j, but propeller underwater radiation noise i does not necessarily propagate in a straight line and must be completely shielded. It has the disadvantage that it cannot be used.

The present invention aims to solve these problems by localizing the noise generated and propagated from own ships in order to maximize the performance of various sensors installed on observation ships, ships, etc. An object of the present invention is to provide a propeller underwater radiation noise shielding type ship that can completely shield propeller underwater radiation noise, which accounts for most of the noise generated in the own ship.

[Means for solving problems]

For this reason, the propeller underwater radiation noise shielding type ship of the present invention,
A propeller is provided at the stern, and an acoustic sensor is provided below the bottom of the ship near the bow.In order to prevent the noise emitted into the water by the propeller from entering the acoustic sensor, both sides and the bottom surface of the propeller are provided. A propeller underwater radiation noise shielding member is provided to surround the propeller, and sound absorbing materials are attached to the inner surface of the propeller underwater radiation noise shielding member and the bottom surface of the ship near the front opening of the propeller underwater radiation noise shielding member. It is said that

[For production]

In the propeller underwater radiation noise shielding type ship of the present invention described above,
The noise radiated from the propeller is absorbed by the sound absorbing material attached to the propeller underwater radiation noise shielding member, and also by the sound absorbing material attached to the bottom of the ship near the front opening of the propeller underwater radiation noise shielding member. , will no longer be sent to the acoustic sensor.

〔Example〕

Hereinafter, embodiments of the present invention will be explained with reference to the drawings.
Figures 1 to 8 show a propeller underwater radiation noise shielding type ship as an embodiment of the present invention. Figure 1 is a side view of the hull, Figure 2 is an enlarged view of the The figure is in Figure 1.
4 is a sectional view taken along the ff-IV arrow in FIG. 1, FIG. 5 is a sectional view taken along the V-■ arrow in FIG. 1, and FIG.
7 is a cross-sectional view taken along the line -■ arrow in FIG. 1, and FIG. 8 is a cross-sectional view taken along the line -■ arrow in FIG. 1.

As shown in Figures 1 to 8, the bow bottom outer plate of the hull 1 is 11 m long.
An acoustic sensor 7 is attached to the , and an acoustic sensor 8 is suspended by a cable 12 .

Two propellers 2 are attached to the propulsion shafts 4 on the stern bottom outer plate 11& of the hull 1, and shaft brackets 3 for supporting the propulsion shafts 4 of each propeller 2 are provided respectively. .

Further, a propeller underwater radiation noise shielding member 6 is provided to cover both sides and the lower surface of the propeller 2 upstream propulsion shaft 4, and the propeller underwater radiation noise shielding member 6 and the stern bottom outer plate 11b form a cylindrical member. 13 is formed, and a sound absorbing material 10 is pasted on the inner surface of this cylindrical member 13.

Furthermore, a partition wall 6c is provided at the center of the cylindrical member 13 so as to separate each propeller 2 and propulsion shaft 4 from each other.

The front opening 1 of the propeller underwater radiation noise shielding member 6
4, that is, the bottom surface of the hull 1 that is directly exposed to the underwater radiation noise 9 from the propeller 3.
A sound absorbing material 10' is attached to 1b.

Further, in the rear opening 15 of the propeller underwater noise shielding member 6, bearing parts 6a, 6a for the rudder 5 are formed at the lower part, and bearing parts 6b, 6b for the rudder 5 are formed at the upper part.

Since the propeller underwater radiation noise shielding type ship as an embodiment of the present invention is constructed as described above, the sound absorbing material 10. ', the noise absorbed and transmitted to the acoustic sensor 7.8 is reduced, and only the signal sound is sent to the acoustic sensor 7.8.

〔Effect of the invention〕

As described in detail above, according to the propeller underwater radiation noise shielding type ship of the present invention, the following effects and advantages can be obtained with a simple structure.

(1) It is possible to localize the noise generated by the own ship's propeller and radiated into the water.

(2) According to the above item 1, it is possible to reduce the propeller underwater radiation noise sent to the acoustic sensor installed on the own ship,
Maximum performance of the acoustic sensor can be guaranteed.

(3) In order to demonstrate the performance of the acoustic sensor, the speed is
There are no behavioral constraints such as changing propeller rotation.

(4) By using this shielding member, the support of the shaft bracket and rudder can be changed from the conventional cantilever support (suspended from the bottom) to the two-point support of the bottom shell plate and the shielding member, which increases the strength of the shaft bracket and rudder. It is structurally advantageous.

(5) The propeller, propulsion shaft, and shaft bracket can be protected from underwater objects, etc. by the noise shielding member.

[Brief explanation of the drawing]

Figures 1 to 8 show a propeller underwater radiation noise shielding type ship as an embodiment of the present invention. Figure 1 is a side view of the hull, Figure 2 is an enlarged view of the The figure is a sectional view taken along the line ■-■ in FIG. 1, FIG. 4 is a sectional view taken along the line IV--■ in FIG. 1st
■-■ cross-sectional view of the figure, Fig. 7 is f:1tJ1 diagram ■-
■A cross-sectional view taken along arrows and @8 are cross-sectional views taken along arrows ■--■ of FIG. 1, and FIGS. 9 and 10 are side views of a ship equipped with a conventional acoustic sensor, respectively. 1... Hull, 2... Propeller, 3... Shaft bracket, 4... Propulsion shaft, 5... Rudder, 6... Propeller underwater radiation noise shielding member, 6a, 6b... Bearing section, 6c... Partition wall , 7.8...Acoustic sensor, 9...Radiation noise, 10.1
0'...sound absorbing material, lla...bow bottom outer plate, 11b
... Stern bottom shell plate, 12 ... Cable, 13 ... Cylindrical member, 1
4...Front opening, 15...Rear opening. Sub-Agent Patent Attorney Yoshihiko Iinuma Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 7 Figure 8

Claims (1)

[Claims] A propeller is provided at the stern, and an acoustic sensor is provided below the bottom of the ship near the bow.In order to prevent the noise emitted into the water by the propeller from entering the acoustic sensor, both sides and the bottom surface of the propeller are provided. A propeller underwater radiation noise shielding member surrounding the propeller is provided, and a sound absorbing material is attached to the inner surface of the propeller underwater radiation noise shielding member and the bottom surface of the ship near the front opening of the propeller underwater radiation noise shielding member, respectively. A propeller underwater radiation noise shielding type ship.