JP2001082399A - Siphon tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten a time required to reach a perfect siphon status by providing another small recirculating pump in the upstream of a first curved portion bent in angle shape from the upper liquid of a water tank so as to form a recirculating loop. SOLUTION: When a pump is operated, liquid from the pump flows from an inflow port 1 to an outflow port 6 and is fed to a water channel and a water tank 7. Because the liquid rises temporarily and lowers in a siphon tube, air bubbles tend to accumulate near the tip part of a first curved part 4. However, because a small recirculating pump 10 other than a pump 1 is provided in the upstream of the first curved portion 4 curved in angle shape from the upper liquid of the water tank 8 so as to form a recirculation loop, a flow rate inside the siphon tube, i.e., a flow velocity inside the siphon tube is increased and an air bubble exhausting action is increased so as to reduce a time required for formation of a perfect siphon.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a siphon tube connected to a discharge side of a pump.

[0002]

2. Description of the Related Art Known Examples JP-A-57-143200, JP-A-57-195900, and JP-A-54-17.
As described in No. 501, the siphon pipe is provided on the discharge side of the pump, and connects the discharge side of the pump and the discharge channel or water tank. FIG. 5 shows a side view of a prior art siphon tube. The inlet 2 of the siphon pipe connected to the discharge side of the pump 1 is attached to the discharge pipe of the pump by an appropriate flange or the like.

A siphon pipe is provided with an ascending portion 3 which rises from the inflow port 1 in a substantially linearly upward direction in the downstream direction.
And a descending portion 4 provided on the downstream side of the first curved portion 4 provided on the downstream side of the rising portion 3 and curved in a chevron shape, and descending so as to be inclined substantially linearly downward. A downstream side of the descending portion 5 is composed of a second curved portion 6 which is curved substantially horizontally toward a water channel or a water tank, and an outlet 7 of the second curved portion communicates with the water tank 8.

Therefore, during operation, the liquid from the pump flows from the inflow port 2 to the outflow port 7 and is sent to a water channel or a water tank. As described above, in the siphon tube, the liquid rises and falls once, so that the bubbles are formed in the first curved portion 4.
Have a tendency to accumulate near the top. However, in reality, bubbles are carried toward the outlet 7 by the flow in the siphon tube, but the flow is separated near the upper portion of the second curved portion 6 on the upstream side of the outlet 7, so that the descending portion 5 is moved. Bubbles sent to the downstream side flow back to the upstream side on the upper surface in the descending portion 5 by buoyancy. When the air bubbles flow backward to the upstream side in this manner, the air discharging action is eliminated, and it is difficult to remove the air bubbles from the siphon tube, and it is insufficient to consider that it takes a long time until a complete siphon state is achieved. In particular, this disadvantage is remarkable when the flow velocity in the siphon tube is 0.8 m / s or less.

[0005] The present invention is directed to a siphon tube in which air bubbles are hardly removed from the siphon tube and it takes a long time to reach a complete siphon state.

[0006]

The above-mentioned known techniques have the following problems. In the prior art siphon tube, insufficient consideration was given to the fact that air bubbles were difficult to be removed from the siphon tube and it took time to reach a complete siphon state.

An object of the present invention is to provide a recirculation loop in the siphon pipe of a pump to increase the flow velocity in the siphon pipe and facilitate the entrainment of air bubbles, thereby shortening the time required for a complete siphon state. is there.

A second object of the present invention is to provide a spray nozzle in the above-mentioned recirculation loop to stir the gas-liquid interface and make it easy for air bubbles to be entrained, thereby shortening the time until a complete siphon state is achieved. It is to shorten.

[0009]

According to the present invention, in order to achieve the above object, according to the present invention, a pump 1 is provided from an upper liquid of the water tank 8 to an upstream portion of a first curved portion 4 which is curved in a chevron shape.
A recirculation loop is formed through a small recirculation pump 10 different from the above.

In order to achieve the above object, according to a second embodiment of the present invention, a spray nozzle is provided at a portion to be recirculated to the chevron portion to spray droplets.

According to the above-mentioned means, the liquid from the upper part of the water tank 8 is re-circulated to the upstream portion of the first curved portion 4 which is curved in the shape of a mountain via a small recirculation pump 10 separate from the pump 1. Since the circulation loop is formed, the flow rate in the siphon pipe, that is, the flow velocity in the siphon pipe becomes larger than that of the conventional one, the air bubble discharging action becomes large, and the time required for forming a complete siphon can be reduced.

According to the above-described means, a spray nozzle is provided at a portion to be recirculated to the chevron portion, and a droplet is sprayed. Therefore, air is entrained at the gas-liquid interface by the droplet, and As a result, the bubble discharging action is increased, and the time required for forming a complete siphon can be reduced.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 shows a side view of a siphon tube according to one embodiment of the present invention. The inlet 2 of the siphon pipe connected to the discharge side of the pump 1 is attached to the discharge pipe of the pump by an appropriate flange or the like. The siphon pipe has an ascending portion 3 which rises substantially linearly upward in the downstream direction from the inflow port 1 and a first curved portion provided on the downstream side of the ascending portion 3 and which is curved in a mountain shape. A descending portion 5 provided on the downstream side of the portion 4 and descending so as to be substantially linearly inclined downward, and a second curve which curves the downstream side of the descending portion 5 in a substantially horizontal direction toward a water channel or a water tank. The second curved portion 6 has an outlet 7 communicating with a water tank 8. Further, a recirculation loop is formed from the upper liquid of the water tank 8 to the upstream portion of the first curved portion 4 which is curved in a mountain shape, via a recirculation pump 10 different from the pump 1. .

Therefore, during operation, the liquid from the pump flows from the inlet 1 to the outlet 6 and is sent to the water channel or the water tank 7. As described above, in the siphon tube, the liquid rises and falls once, so that the bubbles are formed in the first curved portion 4.
Have a tendency to accumulate near the top. However,
Since a recirculation loop is formed from the upper liquid of the water tank 8 to the upstream portion of the first curved portion 4 which is curved in a mountain shape through a small recirculation pump 10 different from the pump 1, the flow rate in the siphon pipe is reduced. That is, the flow rate in the siphon pipe is larger than that of the conventional siphon, the air bubble discharging action is increased, and the time required for complete siphon formation can be reduced.

FIG. 2 is a side view (enlarged view) of a siphon tube according to a second embodiment of the present invention. The recirculation pump 10
The water recirculates from the mountain to the mountain. At this time, the droplet 30 is sprayed from the spray nozzle 20 outside the chevron. The droplet 30 disturbs the interface and entrains surrounding air below the surface of the water. The entrained air is entrained in the water flow, and the air bubble discharging action increases.

Although the flow state of the fluid flowing through the siphon water channel changes, the operation of removing air from the siphon discharge water channel is mainly divided into three functions. First, the pushing action is a phenomenon that occurs for a few seconds immediately after the pump is started, and then the flow state shifts to the air entrainment action and the entrainment action. This phenomenon continues until a complete siphon is formed.

FIG. 3 shows the effect of the flow rate in the siphon pipe according to the present invention. FIG. 3 and FIG. 4 shown later are cited from the literature: Japan Opportunity Society of Japan Hitachi Regional Performance, pp 73-75 (October 3, 1980). In FIG. 3, the vertical axis represents the total pressure at the siphon pipe inlet 2, and the horizontal axis represents time. In each case of the flow rate, the pressure once rises, then gradually falls, and finally stabilizes at a pressure almost close to a constant pressure. The time at which stabilization begins is called the pressure siphon formation time.
The time when air disappears from the siphon is called the complete siphon formation time. Referring to FIG. 3, when the flow rate is large as in the present invention, it is larger than that when the flow rate in the siphon pipe is small. ). FIG. 4 shows the flow rate dependence in the siphon pipe of the pressure siphon formation time and the complete siphon formation time. As can be seen from FIG. 4, according to the present invention, since the flow rate in the siphon pipe is larger than that of the conventional one, there is an effect that the complete siphon formation time is shorter than that of the conventional one. For example, when the small recirculation pump is started and the flow rate in the siphon pipe is increased by about 10%, there is an effect that the time for forming the complete siphon can be reduced to about 1/2.

[0019]

According to the embodiment of the present invention, a recirculation pump 10 separate from the pump 1 is provided from the upper liquid of the water tank 8 to the upstream portion of the first curved portion 4 which is curved in a mountain shape. Since the recirculation loop is formed, the flow rate in the siphon pipe, that is, the flow velocity in the siphon pipe, is larger than that of the conventional siphon pipe, the effect of discharging bubbles is increased, and the time required for forming a complete siphon can be reduced.

According to the second embodiment of the present invention, a spray nozzle 20 is provided at a portion to be recirculated to the chevron, and a droplet 30 is sprayed.
At 0, air is entrained at the gas-liquid interface, entrained by the water flow, the air bubble discharging action is increased, and the time required for complete siphon formation can be further reduced.

[Brief description of the drawings]

FIG. 1 is a side view of a siphon according to an embodiment of the present invention.

FIG. 2 is a side view of a siphon according to another embodiment of the present invention.

FIG. 3 is a diagram showing an effect of a flow rate in a siphon pipe according to one embodiment of the present invention.

FIG. 4 is a diagram showing the flow rate dependence of the pressure siphon formation time and the complete siphon formation time in the siphon pipe.

FIG. 5 is a side view of a conventional siphon tube.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Pump, 2 ... Inlet, 3 ... Ascending part, 4 ... First curved part, 5 ... Falling part, 6 ... Second curved part, 7 ... Outlet, 8 ... Water tank, 10 ... Recirculation pump, 20: spray nozzle, 30: droplet.

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Hitaka Masataka 7-2-1, Omika-cho, Hitachi City, Ibaraki Pref. Hitachi, Ltd. Electric Power and Electric Development Laboratory (72) Inventor Naoyuki Ishida Hitachi, Ibaraki 7-2-1, Omika-cho, Yokohama-shi F-term (reference) in Hitachi, Ltd. Power and Electricity Development Division 3H079 AA26 BB10 CC07 DD22 DD31

Claims (2)

[Claims] An ascending portion provided on the discharge side of the pump, a chevron portion provided downstream of the ascending portion, a descending portion provided downstream of the chevron portion, and a downstream portion of the descending portion. A siphon tube comprising a water tank portion, wherein the water tank portion and the chevron portion are connected via another pump to form a recirculation loop. 2. A siphon tube according to claim 1, wherein a spray nozzle is provided at a portion to be recirculated to the chevron portion to spray droplets.