Hitachi, Ltd.

Other

Akira Manabe

Junichi Kurokawa

Tomoyoshi Okamura

Kouichi Irie

Kunio Takada

Sumio Sudo

Takahide Nagahara

Hitoharu Kimura

Norimitsu Kuwabara

Seiji Miura

Sadashi Tanaka

Kenji Otani

Masayuki Yamada

Tomoyshi Okamura

Yutaka Shimada

For improving characteristic uprising at the right-hand side of head-flow rate characteristic of a turbo machine, as well as for suppressing increase of vibration and/or noises thereof, a plurality of first grooves in direction of gradient in pressure of fluid are formed on an inner flow surface of a casing, for connecting an inlet side of blades of an impeller and an area on the inner flow surface of the casing where the impeller blades reside in, over an inner circumference of the casing. Also, second grooves in a circumferential direction are formed in an area on the inner flow surface of the casing where the impeller blades reside in, for communicating the first grooves in the circumferential direction of the casing.

Turbo machines

A turbo machine comprising: an impeller having a plurality of blades therewith; a casing having a flow surface defined therein and being positioned with the impeller therein; and a plurality of grooves being formed in the flow surface of the casing, for connecting between an inlet side of said impeller and an area on the flow surface of the casing in which the blades of said impeller reside. Each groove has a length of at least part of which is oriented in an axial direction of the casing, a width measured in a circumferential direction, and a depth. The width of each groove is equal to or greater than the depth thereof.

For improving characteristic uprising at the right-hand side of head-flow rate characteristic of a turbo machine, as well as for suppressing increase of vibration and/or noises thereof, a plurality of first grooves,in direction of gradient in pressure of fluid are formed on an inner flow surface of a casing, for connecting an inlet side of blades of an impeller and an area on the inner flow surface of the casing where the impeller blades reside in, over an inner circumference of the casing. Also, second grooves,in a circumferential direction are formed in an area on the inner flow surface of the casing where the impeller blades reside in, for communicating the first grooves in the circumferential direction of the casing.

In a drainage pump station, a driving machine has a capacity greater than a shaft power necessary for no-discharge operation of a pump, and during severe flooding the pump is operated at an overload exceeding its design capacity. During maintenance operation water is fed from a river on the delivery side of the pump station into the station. When an inflow of rainwater into the pump station is great the pump is operated at the necessary capacity, when it becomes small the water level is kept above a rated value, and when the inflow rate is zero the pump discharge is increased to a capacity at which sediment can be discharged. A suction blower is disposed at the top of a suction sump and interstage valves are disposed in entrances of vertical shafts to effect efficient ventilation of the underground waterway. A feed channel is operated as a pressure channel and the pump is of variable capacity and the water level in the underground waterway is controlled to be constant.

Drainage pump station and drainage operation method for drainage pump

In a drainage system wherein drain water is collected from a drainage path including a small river, guided to a plurality of drainage pump facilities, and drained into a destination river, a drainage distribution amount is determined for each of the plurality of drainage pump facilities in accordance with an actual precipitation or estimated precipitation, a river water level at a drainage point of each of the plurality of drainage pump facilities is estimated in accordance with the drainage distribution amount and a change in a detected water level at an upstream of the destination river, and the drainage distribution amount for each of the plurality of drainage pump facilities is corrected so as to make the estimated river water level have a value equal to or smaller than an upper limit of the river water level at the drainage point.

Drainage distribution amount determining method and drainage system

Growing community of inventors

Niihari-gun, Japan

Akira Manabe