JPS5857136B2 - Exchange promotion device - Google Patents

Description

[Detailed Description of the Invention] This invention utilizes the natural energy of ocean currents and water currents such as the sea, rivers, and lakes to generate upwelling currents, descending currents, horizontal currents, etc. in water bodies to promote exchange. It is related to the device.

For example, upwelling currents generated by reefs on the ocean floor or submerged fish reefs promote natural exchange between the bottom water and the upper water, which agitates and lifts useful ingredients and food from the bottom layer, which naturally supports floating fish. Because fish flock to create a good fishing ground, many attempts have been made to create a desirable fishing environment by installing various artificial fish reefs in coastal and bay waters.

However, conventional fish reefs that have been developed for the purpose of generating upwelling currents have a surface structure type, that is, they have walls facing the direction of the flowing water, and the flowing water rises along the walls to generate upwelling currents. The mainstream idea is to
The reality is that it cannot be said that they are necessarily having a reliable and sufficient effect on the generation of upwelling currents.

This invention was made in consideration of the above-mentioned circumstances, and its purpose is to provide an exchange promoting device that can effectively generate upwelling, descending, and horizontal currents by utilizing the energy of ocean currents and water currents. This is what we are trying to provide.

The basic concept of this invention will be explained below with reference to FIG.

In the figure, 1 is the main body of the device, B is a lower opening with an opening area sB provided at a low position on the surface of the main body 1 facing the flowing water, and A is located at a higher position than the opening B. The upper opening has an opening area SA provided on the upper surface, which is one of the flowing water passage surfaces.

2 is the upper and lower opening A. It is a water conduit with a right-angled slit that communicates with B, and its vertical part has a width of 2b and a height of H.

3 is a venturi-type aperture section provided opposite the upper opening A, and has a cross-sectional area S of the aperture entrance.

, S is the effective cross-sectional area of the aperture.

If this device main body 1 is placed in a uniform flow with a flow velocity U where the density of the fluid up to a depth hl from the top of the main body 1 is ρ1, and the density of the fluid below that depth is ρ2, , the pressure PA between the upper and lower parts A and B, that is, the upper and lower vertical parts of the water conduit 2,
The difference between the static pressures PAS and PBS in PB is as follows.

In addition, the flow velocity U8 of the constriction section at the upper opening A is SO/5-U
==, and on the other hand, if the flow velocity U decreases to U at the lower opening B, the yellow difference of the dynamic pressure P 2, an upwelling flow with a flow velocity V can be generated.

The equation of motion for the vertical flow here is assumed to be steady, and assuming that the friction on the side wall of the headrace channel 2 is proportional to the square of the average flow velocity V, and its coefficient is γ2, the flow velocity V of the upwelling flow and the uniform flow The ratio to the flow velocity U is εrh.

becomes.

However, F・2=. lp Uya2 Here, F,2 corresponding to V=Ue is Fyc2 and lp, γ2=(1!=1 to 4°S in the case of LOO3, Fipc2 for the range of m=20 to 100 (7) The relationship between specificity and SA/SB is shown in Figure 2. If F,,2 is smaller than this value, V, > U=,
.

S.H. becomes.

For example -to=0.5. -=50μ crying=2SB
In the case of b S , F, , c2 becomes 1.72.

Therefore εrhl Fyu2 (= Ue.

)≦1.72, it is possible to generate an upwelling flow of V) U=-, , .

Specifically, when g ~I O-3,hl = 500 cm, U is ≧16.88 cm/S, and if the current velocity of the ocean current or water current is higher than this, then the flow velocity V is faster than the current velocity U. It is possible to generate an upwelling current.

In the above description, the shape of the water conduit 2 is a right-angled slit for the sake of simplicity, but the present invention can also be applied to a case where the shape of the water conduit 2 is a linear inclined slit.

In addition, since the upper opening A only needs to be provided at a higher position than the lower opening B and on the flowing water passage surface, it is not limited to the case where it is provided on the top surface of the device main body 1 as described above, but when it is provided on the side surface. It can also be applied to

Furthermore, although the above is a case where the opening B on the side facing the running water is provided below the opening A on the running water passing side, each of the above openings B,
A case where the vertical position of A is reversed or a case where it is arranged horizontally is also included as the above special example, and a downward flow or a horizontal flow can be generated in the water conduit 2.

Next, one embodiment of the present invention will be explained with reference to FIGS. 3 and 4.

This is provided with a lower opening B having a large opening area SB facing the flowing water on both left and right flowing water facing surfaces near the bottom surface 1a of the device main body 1, which has a hollow approximately triangular cross section and has an appropriate width, and a top portion 1b. An upper opening A having an opening area SA smaller than the opening area sB of the lower opening B is provided on the running water passing surfaces on both the left and right sides, and an inclined water conduit 2 having a rectangular cross section that communicates both openings A and B is placed back to back. A plurality of fixing leg portions 1c are provided protruding from the bottom surface 1a for use when submerged in the seabed.

By arranging a large number of these upwelling flow promoting devices in a direction perpendicular to the reciprocating flow in a sea area where tidal currents flow back and forth, upwelling flow can be constantly generated in the water headrace 2 without being caught in the direction of the tidal flow. Upwelling areas can be formed.

In this embodiment, the cross-sectional shape of the water conduit 2 is rectangular, but the water conduit 2 is formed by integrally forming a plurality of tapered water conduits in parallel in which the lower opening area sB is larger than the upper opening area SA. You can also do this.

In addition, if the current speed of the ocean current at the installation location is fast, the upper and lower openings A
, H may be made equal in area; on the other hand, when the flow velocity is slow, the water conduit 2 has a lower opening area SB larger than the upper opening area SA, as in the above embodiment, and is opposite to the upper opening A. The venturi-type constriction section 3 (first
(see figure), sufficient upwelling flow can be generated.

Furthermore, the installation location is not limited to the seabed as in this example;
It can be applied to places with flowing water such as rivers and lakes.

As described above, the exchange promoting device of the present invention can effectively generate exchange (upward, downward, horizontal) by using the natural energy of ocean currents and water currents, and is extremely effective in creating a fishing environment. be.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of an upwelling flow generator model as an example of the present invention, Fig. 2 is an explanatory diagram showing an example of the relationship between the opening area ratio 5 and B F, 2 , and Fig. 3 is an explanatory diagram showing an example of the relationship between the ratio of opening area FIG. 4 is a half-plane longitudinal sectional side view showing an embodiment of the inventive device, and FIG. 4 is a plan view of FIG. 3. 1... Apparatus main body, A... Opening on the side of the flowing water passing surface, B... Opening on the side facing the flowing water, 2...
...Conduit.

Claims (1)

[Claims] 1. Equipped with an opening provided on the water-facing surface of the main body to face the flowing water, an opening provided on the water-flowing surface of the main body, and a water conduit provided in the main body that communicates these two openings. A constriction part for increasing the flow velocity of the passing water is provided opposite to the opening provided on the water passing surface of the main body,
An exchange promoting device characterized in that a forced flow is generated in the water conduit by a difference between static pressure and dynamic pressure of the flowing water at both the openings.