CN202300788U

CN202300788U - Rotating wheel of mixed flow type water turbine

Info

Publication number: CN202300788U
Application number: CN2011204510861U
Authority: CN
Inventors: 康国南; 葛润·古赛尔; 俞成夫; 王江华; 陈幼亮
Original assignee: FOSHAN ANDRITZ TECHNOLOGIES Ltd
Current assignee: Andritz China Ltd
Priority date: 2011-11-15
Filing date: 2011-11-15
Publication date: 2012-07-04
Anticipated expiration: 2021-11-15

Abstract

The utility model discloses a rotating wheel of a water turbine. The rotating wheel comprises an upper crown, a lower ring and a plurality of blades, wherein the blades are connected between the upper crown and the lower ring and comprise main blades and short blades, and the short blades are distributed among the main blades and are shorter than the main blades. The rotating wheel of the water turbine has the advantages that the cavitation erosion of the water turbine can be effectively avoided, and in addition, the efficiency of the water turbine is improved.

Description

Francis turbine runner

Technical field

The utility model relates to a kind of francis turbine runner.

Background technique

Francis turbine is present most widely used water turbine, and water turbine uses and can occur cavitation phenomenon during the course inevitably, in the high head Francis turbine uses at present when cavitation develops into certain phase; The situation of streaming of blade will degenerate, thereby reduce Hydraulic Moment, and water turbine power is descended; Efficient reduces, and along with the generation of cavitation, inevitably flows through meeting formation cavitation corrosion on the parts at water turbine; Slight have only a small amount of erosion point, and under serious situation, the metallic material in cavitation corrosion district is degraded in a large number; Cause the surface to become cellular, even the phenomenon that makes the blade perforation or fall the limit is arranged, be accompanied by the generation of cavitation and cavitation corrosion; Also can produce noise and pressure pulsation, the pulsation whirlpool band in the draft tube especially, when its frequency in case match with the relevant natural frequency of vibration; Then must cause resonance, cause the vibration of unit, the swing of exerting oneself etc., the safe operation of unit in serious threat.

Summary of the invention

The purpose of the utility model is to overcome the defective of existing technology, provides a kind of and can improve Cavitation in Hydraulic Machinery performance, francis turbine runner that efficient is higher.

Its technological scheme is following.

A kind of francis turbine runner comprises crown and following ring and a plurality of blade that is connected between crown and the following ring, and said blade comprises primary blades and short blade, and said short blade is distributed between the primary blades, and said short blade is shorter than primary blades.

Describe in the face of the further technological scheme of the utility model down.

Said primary blades and short blade are circumferentially spaced apart along runner, have and only have a short blade between per two primary blades.

Said blade circumferentially equidistantly evenly distributes along runner.

Advantage or principle in the face of the utility model describes down:

1, a kind of francis turbine runner comprises crown and following ring and a plurality of blade that is connected between crown and the following ring, and said blade comprises primary blades and short blade; Said short blade is distributed between the primary blades, and said short blade is shorter than primary blades, from the fluid mechanics aspect; The blade of water turbine is many more, and is thin more, and the pressure that individual blade receives is few more; Cavitation corrosion will reduce, and therefore between primary blades, installs short blade additional, has increased blade quantity; Correspondingly reduce simultaneously the thickness of original primary blades, improved the cavitation corrosion phenomenon of water turbine;

2, circumferentially spaced apart along runner of primary blades and short blade; Have and only have a short blade between per two primary blades, effective lifting surface area of runner is improved, so the efficient of water turbine increases; And the corresponding reduction of the pressure of blade unit area guarantees that the running of water turbine is more stable;

3, blade circumferentially equidistantly evenly distributing along runner; The energy of water is further utilized; The water velocity of outlet of rotary wheel is lowered, and reduced the pulse counterforce to runner that current bring the impact of draft tube greatly, thereby the running that further guarantees water turbine is stable.

Description of drawings

Fig. 1 is the utility model embodiment's a structural representation;

Fig. 2 is the plan view behind the utility model embodiment's the removal crown.

Description of reference numerals:

1, crown, 2, blade, 21, primary blades, 22, short blade, 3, ring down.

Embodiment

Embodiment in the face of the utility model is elaborated down.

As depicted in figs. 1 and 2, a kind of francis turbine runner comprises crown 1 and following ring 3 and a plurality of blade 2 that is connected between crown 1 and the following ring 3; Said blade 2 comprises primary blades 21 and short blade 22, and said short blade 22 is distributed between the primary blades 21, and said short blade 22 is shorter than primary blades 21; According to fluid mechanics knowledge, the blade 2 of water turbine is many more, and is thin more; The pressure that individual blade 2 receives is few more, and cavitation corrosion will reduce, and therefore between primary blades 21, installs short blade 22 additional; Increase blade 2 quantity, correspondingly reduced the thickness of original primary blades 21 simultaneously, improved the cavitation corrosion phenomenon of water turbine.

Primary blades 21 and short blade 22 are circumferentially spaced apart along runner, have and only have a short blade 22 between per two primary blades 21, and said blade 2 circumferentially equidistantly evenly distributes along runner; Water turbine is stressed evenly; Effective lifting surface area of runner is improved, so the increase of the efficient of water turbine, and the corresponding reduction of pressure of blade 2 unit areas; The energy of water is further utilized; The water velocity of outlet of rotary wheel is lowered, and reduced the pulse counterforce to runner that current bring the impact of draft tube greatly, thereby the running that further guarantees water turbine is stable.

Primary blades 21 is 15 with short blade 22 in the present embodiment, and in fact, primary blades 21 is decided according to different rotary wheel of water turbine performance requirements with the quantity and the thickness of short blade 22; According to fluid mechanics knowledge, blade is many more, and is thin more; Cavitation corrosion will reduce, therefore, and for the rotary wheel of water turbine of different performance; Under the situation that satisfies the strength and stiffness requirement, should make the quantity of blade many as far as possible, the thickness of blade is thin as far as possible, to improve the cavitation corrosion phenomenon better.

More than be merely the specific embodiment of the utility model, do not limit the protection domain of the utility model with this; Do not violate any replacement and the improvement of being done on the basis of the utility model design, all belonging to the protection domain of the utility model.

Claims

1. a francis turbine runner comprises crown and following ring and a plurality of blade that is connected between crown and the following ring, it is characterized in that said blade comprises primary blades and short blade, and said short blade is distributed between the primary blades, and said short blade is shorter than primary blades.

2. rotary wheel of water turbine as claimed in claim 1 is characterized in that, said primary blades and short blade are circumferentially spaced apart along runner, has and only have a short blade between per two primary blades.

3. rotary wheel of water turbine as claimed in claim 1 is characterized in that, said blade circumferentially equidistantly evenly distributes along runner.