阅读说明：本技术 一种双吸式吸入管非均匀来流主动控制的轴流泵 (Axial flow pump with double-suction type suction pipe for actively controlling non-uniform incoming flow ) 是由 龙云 陈一鸣 朱荣生 安策 王秀礼 付强 于 2019-09-20 设计创作，主要内容包括：本发明提供了一种双吸式吸入管非均匀来流主动控制的轴流泵,包括泵体、叶轮和导叶,所述泵体入口安装双吸式弯管,所述双吸式弯管包括两个进口和一个出口,两个所述进口按照出口中心对称分布；所述出口与所述泵体入口连接；所述进口内壁分布适流叶片。所述适流叶片包括上适流叶片和可调节流叶片装置,所述双吸式弯管进口的内壁上侧沿径向等距分布若干上适流叶片,所述双吸式弯管进口的内壁下侧设有可调节流叶片装置,用于改变进入所述进口流体的轴向速度、径向速度和绝对入流角度。本发明利用弯管内设置的非均匀来流主动控制装置,使得轴流泵入口的轴向速度、径向速度和绝对入流角度产生畸变,调整了非均匀来流,从而提高了轴流泵泵性能。(The invention provides an axial flow pump with a double-suction pipe for actively controlling non-uniform incoming flow, which comprises a pump body, an impeller and a guide vane, wherein a double-suction elbow is arranged at an inlet of the pump body, the double-suction elbow comprises two inlets and an outlet, and the two inlets are symmetrically distributed according to the center of the outlet; the outlet is connected with the pump body inlet; the inner wall of the inlet is distributed with flow adapting blades. The flow adapting blade comprises a plurality of flow adapting blades and an adjustable throttling blade device, the upper side of the inner wall of the inlet of the double-suction elbow is distributed with a plurality of flow adapting blades along the radial direction at equal intervals, and the lower side of the inner wall of the inlet of the double-suction elbow is provided with the adjustable throttling blade device for changing the axial speed, the radial speed and the absolute inflow angle of the inlet fluid. The invention utilizes the active control device of non-uniform inflow arranged in the elbow to lead the axial speed, the radial speed and the absolute inflow angle of the inlet of the axial flow pump to generate distortion, and adjusts the non-uniform inflow, thereby improving the performance of the axial flow pump.)

1. The axial flow pump with the double-suction type suction pipe for active control of non-uniform incoming flow comprises a pump body (5), an impeller (6) and guide vanes (7), and is characterized in that a double-suction type bent pipe (1) is installed at an inlet of the pump body (5), the double-suction type bent pipe (1) comprises two inlets and one outlet, and the two inlets are symmetrically distributed according to the center of the outlet; the outlet is connected with the inlet of the pump body (5); the inner wall of the inlet is distributed with flow adapting blades for changing the axial velocity, the radial velocity and the absolute inflow angle of the fluid entering the inlet.

2. The axial flow pump with the double-suction type suction pipe for active control of nonuniform incoming flow according to claim 1, characterized in that the adaptive flow vanes comprise adaptive flow vanes (2) and adjustable throttle vane devices, a plurality of adaptive flow vanes (2) are radially and equidistantly distributed on the upper side of the inner wall of the inlet of the double-suction type elbow pipe (1), and the adjustable throttle vane devices are arranged on the lower side of the inner wall of the inlet of the double-suction type elbow pipe (1) and are used for changing the axial velocity, the radial velocity and the absolute inflow angle of the fluid entering the inlet.

3. The axial flow pump with active control of uneven inflow of double suction pipe according to claim 2, characterized in that the adjustable throttle blade arrangement comprises lower adaptive flow blades (3), adjusting blades (302), front limit pins (303) and rear limit pins (304); lower adaptive flow blades (3) are symmetrically arranged at the center of the lower side of the inner wall of the inlet of the double-suction elbow (1), and swingable adjusting blades (302) are arranged between the symmetrically arranged lower adaptive flow blades (3); the front limit pin (303) and the rear limit pin (304) are used for limiting the swing size of the adjusting blade (302).

4. The axial flow pump with the double suction type suction pipe for active control of uneven inflow according to claim 3, wherein the adjusting blades (302) are installed on a rotating pin shaft (301), and two ends of the rotating pin shaft (301) are installed between the lower adaptive flow blades (3) which are symmetrically arranged.

5. The axial flow pump with active control of uneven inflow of double suction pipe according to claim 3, characterized in that the front stopper pin (303) and the rear stopper pin (304) are detachably mounted on the lower adaptive flow blade (3), respectively, and the front stopper pin (303) and the rear stopper pin (304) limit the swing of the adjustable blade (302) to not more than 10 °.

6. The axial flow pump with active control on uneven inflow of double-suction type suction pipe according to claim 1, characterized in that the inner wall of the double-suction type elbow pipe (1) is provided with a water guiding cone (4), and the water guiding cone (4) is located at the junction of the two inlets for guiding the two inlet fluids to the outlet of the double-suction type elbow pipe (1).

7. The axial flow pump with the double-suction type suction pipe for active control of nonuniform incoming flow according to claim 6, wherein the height of the flow guide cone (4) is 0.7-0.8 times of the nominal diameter of the double-suction type bent pipe (1).

8. The axial flow pump with double suction pipe for active control of uneven inflow according to claim 2, characterized in that the number of blades of the impeller (6) is n and the number of blades of the upper adaptive flow blade (2) is n + 1.

Technical Field

The invention relates to the field of fluid mechanical engineering, in particular to an axial flow pump with a double-suction pipe for active control of non-uniform incoming flow.

Background

Currently, in practical engineering applications, there are many related researches on the fact that various types of pumps may have non-uniform inlet velocity profiles, and the velocity profiles have a certain influence on the performance of the pumps. The Wangfu et al have studied the coupling characteristics of elbow-shaped water inlet channel and axial-flow pump, and have found that the flow velocity distribution on the cross section of the pump inlet is not uniform, which indicates that the coupling action of water inlet channel and pump is obvious, and the internal flow mechanism of pump caused by the coupling of the two channels must be deeply studied. The influence of different inlet speed distributions on the external characteristics, radial load and typical position pressure pulsation of the axial flow pump is contrastively analyzed through numerical calculation by the Shiweidong and the like, and the influence of different inflow conditions on the lift, efficiency, radial force and pressure pulsation characteristics of the axial flow pump is considered to be different. Allen et al found that the water inlet channel causes velocity distortion at the pump inlet, which in turn causes pre-swirl, localized flow separation, and cavitation. Guo et al conducted research on marine propulsion pumps, examined flow distribution and velocity distribution under inflow distortion, and analyzed the causes of inflow distortion.

In summary, the inlet of the axial flow pump is a water inlet channel under the condition of non-uniform inflow, so that the inlet speed of the axial flow pump is distorted, the problems of prewhirl, local flow separation, cavitation and the like are caused, and the lift and the torque of the axial flow pump are reduced, so that the performance of the axial flow pump is affected.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides an axial flow pump with a double-suction pipe for actively controlling non-uniform incoming flow, wherein a double-suction front bent pipe is arranged at the inlet of the axial flow pump, and a non-uniform incoming flow active control device arranged in the bent pipe is utilized to distort the axial speed, the radial speed and the absolute incoming flow angle of the inlet of the axial flow pump, so that the non-uniform incoming flow is adjusted, and the performance of the axial flow pump is improved.

The present invention achieves the above-described object by the following technical means.

The axial flow pump comprises a pump body, an impeller and guide vanes, wherein a double-suction type bent pipe is arranged at an inlet of the pump body, the double-suction type bent pipe comprises two inlets and an outlet, and the two inlets are distributed according to the outlet center symmetry; the outlet is connected with the pump body inlet; the inner wall of the inlet is distributed with flow adapting blades for changing the axial velocity, the radial velocity and the absolute inflow angle of the fluid entering the inlet.

Furthermore, it flows the blade including last suitable for the class blade and adjustable throttle blade device to be described, the inner wall upside of double-suction elbow inlet radially distributes a plurality of suitable for the class blades along the equidistance, the inner wall downside of double-suction elbow inlet is equipped with adjustable throttle blade device for change get into the axial velocity, the radial velocity and the absolute inflow angle of import fluid.

Further, the adjustable throttling blade device comprises a lower flow adapting blade, an adjusting blade, a front limit pin and a rear limit pin; lower adaptive flow blades are symmetrically arranged at the center of the lower side of the inner wall of the inlet of the double-suction elbow, and swingable adjusting blades are arranged between the symmetrically arranged lower adaptive flow blades; the front limit pin and the rear limit pin are used for limiting the swing size of the adjusting blade.

Furthermore, the adjusting blades are arranged on a rotating pin shaft, and two ends of the rotating pin shaft are arranged between the lower flow adaptation blades which are symmetrically arranged.

Further, the front limit pin and the rear limit pin are respectively detachably mounted on the lower flow-adapting blade, and the front limit pin and the rear limit pin limit the swing of the adjusting blade to be not more than 10 degrees.

Furthermore, the inner wall of the double-suction type elbow is provided with a water guide cone, and the water guide cone is positioned at the intersection of the two inlets and is used for guiding the two inlet fluids to the outlet of the double-suction type elbow.

Further, the height of the flow guide cone is 0.7-0.8 times of the nominal diameter of the double-suction type elbow.

Furthermore, the number of the impeller blades is n, and the number of the upward flow-adapting blades is n + 1.

The invention has the beneficial effects that:

When most axial-flow pumps run in practice, the overall performance of the pump is reduced due to the fact that non-uniform incoming flow exists at the inlet, the efficiency of a pump unit is influenced, and abnormal flow caused by the non-uniform incoming flow even causes abnormal vibration of the pump unit. The double-suction type front-mounted bent pipe is arranged at the inlet of the axial flow pump, the blade self-adaptive angle adjustment can be carried out by utilizing the non-uniform inflow active control device arranged in the bent pipe according to the inflow speed, so that the axial speed, the radial speed and the absolute inflow angle of the inlet of the axial flow pump are changed, the non-uniform inflow is adjusted, the pump performance of the axial flow pump is improved, the pump unit efficiency is improved, and the unit vibration is reduced.

Drawings

FIG. 1 is a schematic structural diagram of an axial flow pump with active control of non-uniform inflow of a double-suction pipe according to the present invention;

FIG. 2 is a top view of a double suction intake pipe non-uniform incoming flow actively controlled axial flow pump according to the present invention;

FIG. 3 is an enlarged view of a portion of a dual suction intake tube non-uniform incoming flow actively controlled axial flow pump according to the present invention;

3 fig. 3 4 3 is 3 a 3 schematic 3 view 3 a 3- 3 a 3 of 3 fig. 3 2 3. 3

In the figure:

1-suction type bent pipe; 2-upper flow-adapting blades; 3-lower adaptive flow blades; 301-rotating the pin; 302-adjusting the blades; 303-front limit pin; 304-rear limit pin; 4-a flow guide cone; 5-a pump body; 6-impeller; 7-guide vanes.

Detailed Description

the invention will be further described with reference to the following figures and specific examples, but the scope of the invention is not limited thereto.

As shown in fig. 1 and 2, the axial flow pump with the double-suction type suction pipe for active control of non-uniform incoming flow according to the present invention includes a pump body 5, an impeller 6 and a guide vane 7, wherein the pump body 5 is provided with the guide vane 7, the impeller 6 is arranged below the guide vane, the double-suction type bent pipe 1 is installed in cooperation with the pump body 5, the double-suction type bent pipe 1 includes two inlets and one outlet, and the two inlets are symmetrically distributed according to the outlet center; the outlet is connected with the inlet of the pump body 5; the inner wall of the inlet is distributed with flow adapting blades for changing the axial velocity, the radial velocity and the absolute inflow angle of the fluid entering the inlet.

The flow adapting blade comprises a plurality of flow adapting blades 2 and adjustable throttling blade devices, the upper side of the inner wall of the inlet of the double-suction type elbow pipe 1 is distributed with the flow adapting blades 2 along the radial direction at equal intervals, and the lower side of the inner wall of the inlet of the double-suction type elbow pipe 1 is provided with the adjustable throttling blade devices for changing the axial speed, the radial speed and the absolute inflow angle of the inlet fluid.

the adjustable throttling blade device comprises a lower adaptive flow blade 3, an adjusting blade 302, a front limit pin 303 and a rear limit pin 304; lower adaptive flow blades 3 are symmetrically arranged at the center of the lower side of the inner wall of the inlet of the double-suction elbow 1, and swingable adjusting blades 302 are arranged between the symmetrically arranged lower adaptive flow blades 3; the front limit pin 303 and the rear limit pin 304 are used for limiting the swing size of the adjustment blade 302. The adjusting blades 302 are installed on a rotating pin shaft 301, and two ends of the rotating pin shaft 301 are installed between the lower adaptive flow blades 3 which are symmetrically arranged.

the inner wall of the double-suction type elbow pipe (1) is provided with a water guide cone (4), and the water guide cone (4) is positioned at the intersection of the two inlets and is used for guiding the two inlet fluids to the outlet of the double-suction type elbow pipe (1).

The double-suction type bent pipe 1 adopts a symmetrical structure with double flange interfaces; if the number of the blades of the impeller 6 is n, the number of the upward flow-adapting blades uniformly arranged on the upper wall surface of the double-suction type bent pipe 1 is n + 1; the number of the lower adaptive flow blades is 2, the lower adaptive flow blades 3 are provided with mounting holes matched with blade roots 301 of the adjusting blades and mounting threaded holes matched with front limit pins 303 and rear limit pins 304, and the front limit pin groups 303 and the rear limit pin groups 304 are movable plug pin groups; the adjusting blade 302 can perform self-adaptive angle adjustment according to the size of the incoming flow speed, and the adjusting range of the adjusting blade is determined by the positions of a front limiting pin 303 and a rear limiting pin 304 which are arranged on the lower adaptive flow blade; the height of the diversion cone 4 is 0.7-0.8 times of the nominal diameter of the double-suction elbow 1.

generally, when the pump set is operated, the flow velocity at the upper wall surface of the preposed bent pipe is different from the flow velocity at the lower wall surface, which causes the inflow of the axial flow pump inlet to be in a non-uniform state, thereby generating a flow separation phenomenon. During flow separation, vortex is often generated, and the more serious part of the flow separation is vortex more obviously, so that the hydraulic loss is increased, the inlet flow velocity distribution is influenced, and the performance of the axial flow pump is reduced. In the invention, when the pump set is operated, the flow speed can be reduced when the inlet incoming flow passes through the upper adaptive flow blade 2, and meanwhile, when the inlet incoming flow passes through the lower adaptive flow blade 3, the incoming flow changes horizontal motion into vertical motion, and the flow speed can be further improved under the self-adaptive angle adjustment of the adjusting blade 302. When the liquid flows through the guide cone 4, the circumferential flow and the annular quantity which can occur are weakened, and the flow state uniformity is greatly improved. Therefore, liquid flow can enter the axial flow pump in a uniform state, the ideal conditions of uniform inflow, no rotation and axial water inflow are met, the pressure pulsation of the axial flow pump is reduced, the efficiency of the axial flow pump is improved, and the running stability of the axial flow pump is further improved.

The present invention is not limited to the above-described embodiments, and any obvious improvements, substitutions or modifications can be made by those skilled in the art without departing from the spirit of the present invention.