JPH0512152Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention relates to a smoke prevention device for ships.

(Prior art) A multi-story structure (generally referred to as a superstructure) that forms living quarters is built on the upper deck above the engine room of a ship, and the chimney is usually located at the rear of the superstructure. It is installed so as to protrude vertically through it.

When a ship is sailing, most of the airflow caught at the front of the superstructure flows upward along the front of the superstructure, and above the top of the superstructure, it joins with the airflow flowing straight from the front. As shown in FIG. 7, a turbulent region that becomes thicker toward the rear from the upper front edge of the upper structure 101 occurs, and when smoke from the chimney is caught in this turbulent region, the smoke spirals downward. The problem is that it spreads over a wide area and causes smoke pollution around residential areas.

In order to prevent the above-mentioned smoke damage, it is necessary to make the chimney protrude above the turbulence boundary surface D, but in this case, not only does resistance due to wind pressure increase, but also the construction cost increases.

Therefore, for example, in Utility Model Publication No. 45-31625,
As shown in FIG. 7, a current plate 104 is installed horizontally at the top end of the superstructure 101 in front of the ship's chimney 102, and this current plate 104 is supported by a plurality of vertical support plates (as shown in the figure). A smoke pollution prevention device 103 for a ship is described which is supported by (omitted).

The front end of the rectifier plate 104 of this smoke pollution prevention device 103 is bent downward as shown in the figure, and is formed to increase the efficiency of air flow from below.

Further, the rectifier section 104 is formed to be relatively short in the ship's ship direction, and is arranged substantially horizontally in both the ship's width direction and ship's ship direction over the entire width of the superstructure 101, and the plurality of support plates are formed in a plan view. It is arranged parallel to the ship's ship direction.

(Problem to be solved by the invention) In the smoke pollution prevention device described in the above publication, most of the rectifier plates, which are relatively short in the longitudinal direction, are arranged horizontally. When rectifying a flowing airflow, the upward velocity component of the airflow tends to remain, so the turbulence boundary surface cannot be sufficiently lowered, and the shape of the rectifier plate narrows the internal passage toward the downstream side. Because it is not formed in the shape of a ship, it does not have the ability to accelerate airflow, and because the multiple support plates are arranged in the direction of the ship's ship,
lack of ability to direct airflow toward the chimney;
Due to the above two reasons, the ability to push exhaust smoke backwards is poor, and the baffle plate is susceptible to crosswinds that tend to cause turbulence diagonally behind the baffle plate.
There are other problems.

(Means for Solving the Problems) The smoke pollution prevention device for a ship according to the present invention includes a rectifier plate provided at the front end of the upper end of the superstructure in front of the ship's chimney, and a vertical plate that supports the rectifier plate. In the smoke pollution prevention device comprising a plurality of support plates, the rectifier plate is formed in a downwardly inclined rearward shape and a mid-height shape that becomes higher toward the center in the width direction of the ship, and each of the plurality of support plates is It is oriented to guide the airflow towards the chimney.

(Function) In the ship smoke prevention device according to the present invention,
Since the rectifying plate is formed in a backward downward slope, the airflow flowing into the rectifying plate is directed in the backward downward direction, which makes it easier to lower the height of the turbulent boundary surface and reduce smoke damage. Become.

Since the above-mentioned rectifier plate is formed in an inclined shape that slopes backward, and each of the plurality of support plates is oriented so as to guide the airflow toward the chimney, the nozzles of the rectification plate and the plurality of support plates Due to this action, the airflow flowing into the current plate is accelerated.

Moreover, since the current plate is formed in a medium-height shape, and each of the plurality of support plates is oriented so as to guide the airflow toward the chimney, the downstream side of the current plate is located at the center in the width direction of the ship. A mainstream of accelerated high-speed airflow begins to form near the chimney. As a result, it is possible to forcefully push the exhaust smoke backwards, making it easier to reduce smoke damage. Note that the current plate is formed in a medium-height shape and is not easily affected by crosswinds, so that turbulence is less likely to occur diagonally behind the current plate, and exhaust smoke is less likely to be engulfed.

(Effect of the invention) According to the smoke pollution prevention device for a ship according to the invention, as explained in the section of the above-mentioned effect, the height of the turbulence boundary surface is reduced by imparting a downward velocity component to the airflow using the baffle plate. This makes it easier to reduce smoke damage.

In addition, the nozzle action of the rectifying plate and the plurality of support plates accelerates the airflow into a high-speed airflow, directs the main stream of the high-speed airflow toward the vicinity of the chimney, and has the effect of forcefully pushing the exhaust smoke backwards. This makes it easier to reduce smoke damage.

In addition, the current plate is formed in a medium-height shape and is not easily affected by crosswinds, so that turbulence is less likely to occur diagonally behind the current plate, and exhaust smoke is less likely to be engulfed.

(Example) Hereinafter, an example of the present invention will be described based on the drawings.

As shown in Figures 1 to 4, a chimney is provided vertically penetrating the rear central part of the superstructure 1 where the living quarters of the ship are formed, and the front part of the superstructure 1 is located in front of the chimney 2. It is located in

At the front end of the upper end of the upper structure 1 in front of the chimney 2, a smoke prevention device 3 is provided as follows, and the smoke prevention device 3 spans about 2/3 of the total width of the upper structure.

The smoke pollution prevention device 3 is composed of a rectifying plate 4 which is curved into a substantially partially conical shape, and three vertical supporting plates 5 that connect the rectifying plate 4 to the upper structure 1.

The baffle plate 4 is formed in a medium-height shape that becomes higher toward the center in the width direction of the ship, and is also formed to be slightly inclined downwardly toward the rear with respect to the horizontal. The left and right side edges of the current plate 4 are joined to the top deck 1b of the upper structure 1.

Three support plates 5 are provided vertically between the current plate 4 and the top deck 1b at positions where the current plate 4 is divided into four equal parts of the widthwise span of the ship, and these three support plates 5 are placed on the inside of the current plate 4. The support plates 5 are disposed in a front-open state so as to guide the airflow flowing into the chimney 2 toward the chimney 2.
The lower edges of are respectively joined to the top deck 1b.

Next, to explain the function of the smoke pollution prevention device 3, as shown in FIG.
The airflow that is received by the baffle plate 4 and rises along the front surface 1a flows into the inside of the baffle plate 4, and is directed backward and downward by the baffle plate 4, as well as the flow path formed by the buff plate 4 and the top deck 1b Since the cross-sectional area becomes smaller toward the downstream side, the airflow is accelerated by the baffle plate 4 and flows toward the chimney 2 as shown in the figure.

In FIG. 3, the airflow that has passed through the baffle plate 4 flows along a high-speed air area A, and a turbulent area B is formed below this high-speed air area A.
A relatively weak turbulence area C is formed above the turbulence area.

Even if the smoke coming out of the chimney 2 is caught in the turbulence area C and flows into the high-speed air area A, it will flow backwards along with the airflow of the high-speed air area A, so the turbulent area below the high-speed air area A The probability that smoke will be engulfed by B is extremely small.

Moreover, the guiding action of the support plate 5 directs the main stream of airflow toward the chimney 2.
Because the airflow in the high-speed air region A near the area becomes faster, smoke damage is less likely to occur.

The guiding action of the support plate 5 is particularly effective when a crosswind is blowing and the airflow from diagonally forward flows into the inside of the rectifying plate 4, as shown in FIG.

Since the rectifier plate 4 is formed in a mid-height shape that becomes higher toward the center in the width direction of the ship, resistance to crosswinds is reduced.

Note that the shape of the baffle plate 4 and the arrangement of the support plate 5 may be changed as shown in FIGS. 5 and 6.

[Brief explanation of the drawing]

Figures 1 to 6 of the drawings show an embodiment of the present invention. Figure 1 is a perspective view of the main parts of the upper structure and chimney equipped with a smoke prevention device, and Figure 2 is a front view of the smoke prevention device. Figure 3 is a partially cutaway vertical side view of the superstructure and chimney equipped with a smoke prevention device, Figure 4 is a plan view of the same, and Figures 5 and 6 are second views of modified examples.
FIG. 7 is a diagram equivalent to FIG. 3 according to the prior art. 1... Upper structure, 2... Chimney, 3... Smoke damage prevention device, 4... Rectifier plate, 5... Support plate.

Claims (1)

[Scope of Claim for Utility Model Registration] In a smoke pollution prevention device comprising a rectifier plate provided at the front end of the upper end of a superstructure in front of a ship's chimney, and a plurality of vertical support plates supporting the rectifier plate. , The baffle plate is formed in a shape that slopes downward toward the rear and has a mid-height shape that becomes higher toward the center in the width direction of the ship, and each of the plurality of support plates is oriented so as to guide the airflow toward the chimney. A ship smoke prevention device characterized by: