CN105864099A - Design method for outlet-end folded edge blade structure of impeller of middle-high-ratio rotating speed centrifugal pump - Google Patents

Abstract

The invention provides a design method for an impeller of an outlet-end folded edge blade structure of a middle-high-ratio rotating speed centrifugal pump. Blades are staggered and thickened at the position of an outlet of the impeller through the folded edge blades, and the staggered blades are designed to have different outlet placement angles and wrap angles and have different widths at the position of the outlet of the impeller. According to the requirement of the folded edge blades, the impeller inlet equivalent diameter, the impeller inlet diameter, the impeller outlet diameter, the impeller outlet width, the blade outlet placement angles, the blade wrap angles, the arc length corresponding to the outlet position between the folded edge upper blade and the folded edge lower blade of the impeller and the blade thickness at the outlet position of the impeller are reasonably designed. The situations that in the running process of the middle-high-ratio rotating speed centrifugal pump, the relative movement of liquid in the impeller is affected by axial vortexes, the hydraulic performance is affected, wake flow at the outlet of the impeller exists and the dynamic-static interference of a pumping chamber happens are improved.

Description

A kind of method for designing of middle higher specific speed centrifugal pump impeller port of export edge folding blades structure

Technical field

The present invention relates to higher specific speed impeller vane of centrifugal pumps construction design method in one, particularly to higher specific speed in one The method for designing of centrifugal pump impeller port of export edge folding blades structure.

Background technology

Pump is a kind of application universal machine the most widely, of a great variety, has inseparable relation with the life of the mankind, all It is the place having liquid to flow, nearly all has the operation work of pump.Along with scientific and technological level constantly improves, the neck that pump uses Territory the most constantly expands.Centrifugal pump structure is varied, is the one being most widely used in various pump, is widely used in city In each department of the social lifes such as feedwater, petrochemical industry, shipping industry, space flight and aviation, agricultural irrigation and national economy.Cause This proposes the highest requirement to centrifugal pump performance, the requirement that runs such as inclined stable conditions, the requirement of low-noise vibrating and High reliability etc..Traditional centrifugal pump impeller Hydraulic Design Method is theoretical and the combination of experience, the most at utmost meets constantly Occur newly designs requirement.Therefore, in order to continue to meet, these constantly occur newly designs requirement, need to improve structure design, Place short blade at impeller channel near exit exactly such as the design of low-specific-speed short blade offset and can improve the water in impeller and the pump housing Power performance.In middle higher specific speed centrifugal pump running, due in impeller liquid relative motion under the influence of axial whirlpool easily The separation of flow at blade exit, affects the hydraulic performance of pump, and middle higher specific speed wake effect pressure of impeller outlet in running Flowing in hydroecium, causes stator-rotor interaction.

Summary of the invention

For problem produced in middle higher specific speed centrifugal pump running, the invention provides higher specific speed centrifugal pump in one The method for designing of impeller outlet end edge folding blades structure.Blade is made to stagger at impeller outlet thickening by edge folding blades, design mistake The blade opened has different outlet laying angles and cornerite and has different width at impeller outlet, closes according to the requirement of edge folding blades Reason designs the import equivalent diameter of impeller, impeller inlet diameter, impeller outlet diameter, impeller outlet width, blade exit peace Put vane thickness at arc length that between angle, subtended angle of blade, the upper and lower blade of impeller flanging, exit is corresponding, impeller outlet, in improvement Higher specific speed centrifugal pump in running in impeller liquid relative motion at axial whirlpool on affecting hydraulic performance and impeller outlet Wake flow and the stator-rotor interaction of pumping chamber.Can effectively alleviate blade loads, higher specific speed centrifugal pump impeller in running in improvement Interior liquid relative motion is at the axial whirlpool wake flow on affecting hydraulic performance and impeller outlet and the stator-rotor interaction of pumping chamber；In realization State purpose be the technical scheme is that

1, impeller inlet equivalent diameter D₀Determined by following formula:

$D_0=\left\{\begin{array}{c}\left(0.4n^{-0.8}{Q}^{0.15}{H}^{0.45}+0.09H\right)\sqrt[3]{\frac{Q}{n}}\left(H\≤50\right)\\ \left(0.84n^{0.4}{Q}^{0.25}{H}^{-0.3}+50H^{-1.21}+4.5\right)\sqrt[3]{\frac{Q}{n}}\left(H>50\right)\end{array}\right.$

In formula:

D₀Impeller inlet equivalent diameter, m；

Q flow, m³/s；

H lift, m；

N rotating speed, rev/min；

2, impeller blade entrance width b₁Determined by below equation:

$b_1=\left\{\begin{array}{c}0.5Q^{0.5}{H}^{-0.25}-\frac{1.1}{n}{H}^{0.5}(H\≤50)\\ \frac{-0.0072nQ}{H}+1.12Q^{0.5}{H}^{-0.25}-\frac{24}{n}{H}^{0.5}(H>50)\end{array}\right.$

In formula:

b₁Impeller blade entrance width, m；

N rotating speed, rev/min；

Q flow, m³/s；

H lift, m；

3, impeller outlet diameter D₂Determined by following formula:

$D_2=\left\{\begin{array}{c}49.5\left(1.3Z^{0.04}-1.1\right)\left(0.0002H+0.88\right)n^{-0.83}{Q}^{-0.1}{H}^{0.375}\left(H\≤50\right)\\ 49.5\left(0.016Z+0.934\right)\left(0.06932InH+0.72\right)n^{-0.83}{Q}^{-0.1}{H}^{0.375}\left(H>50\right)\end{array}\right.$

In formula:

D₂Impeller outlet diameter, m；

The Z number of blade, piece；

N rotating speed, rev/min；

Q flow, m³/s；

H lift, m；

4, blade exit lays angle beta₂Size is determined by following formula:

A angle beta is laid in the outlet of () impeller flanging blade₂₁Determined by below equation:

${\mathrm{\β}}_{21}=\left\{\begin{array}{c}H(0.47+4.5\frac{Z}{H}-0.13Z)(H\≤50)\\ H(0.7+4.2\frac{Z}{H}-0.16Z+0.02)(H>50)\end{array}\right.$

B angle beta is laid in the outlet of () impeller flanging lower blade₂₂Determined by below equation:

${\mathrm{\β}}_{22}=\left\{\begin{array}{c}H(1.4Z^{0.04}-0.11)(0.5+4.7\frac{Z}{H}-0.11Z)(H\≤50)\\ H(0.0003H+0.9)(0.85+4.5\frac{Z}{H}-0.16Z)(H>50)\end{array}\right.$

In formula:

β₂₁Blade outlet laying angle, °；

β₂₂Lower blade outlet laying angle, °；

H lift, m；

The Z number of blade, piece；

5, blade exit width b₂Size is determined by following formula:

(a) impeller flanging blade exit width b₂₁Determined by below equation:

$b_{21}=0.0057(-0.005D_2^2+0.03D_2+0.987)n^{0.5}{Q}^{0.5}{H}^{-0.5}$

(b) impeller flanging lower blade exit width b₂₂Determined by below equation:

$b_{22}=0.0013(-0.006D_2^2+0.031D_2+0.99)n^{0.5}{Q}^{0.5}{H}^{-0.5}$

In formula:

D₂Impeller outlet diameter, m；

b₂₁Blade exit width, m；

b₂₂Lower blade exit width, m；

N rotating speed, rev/min；

Q flow, m³/s；

H lift, m；

6, subtended angle of bladeSize is determined by following formula:

(a) impeller flanging blade corneriteDetermined by below equation:

(b) impeller flanging lower blade corneriteDetermined by below equation:

In formula:

Blade cornerite, °；

Lower blade cornerite, °；

D₀Impeller inlet equivalent diameter, m；

D₂Impeller outlet diameter, m；

H lift, m；

7, the arc length size that between the upper and lower blade of impeller flanging, exit is corresponding is determined by below equation:

In formula:

The arc length that between the upper and lower blade of l impeller flanging, exit is corresponding, m；

D₂Impeller outlet diameter, m；

Blade cornerite, °；

Lower blade cornerite, °；

8, the exit thickness S of impeller blade₂Determined by below equation:

(a) impeller flanging blade exit thickness S₂₁Determined by below equation:

$S_{21}=\frac{-0.05D_0^2+14.21D_0-0.2}{1.3D_0+90}$

(b) impeller flanging lower blade exit thickness S₂₂Determined by below equation:

$S_{22}=-0.55D_0^2+0.13D_0+0.015$

In formula:

S₂₁Impeller flanging blade exit thickness, m；

S₂₂Impeller flanging lower blade exit thickness, m；

D₀Impeller inlet equivalent diameter, m.

The invention has the beneficial effects as follows:

By the optimum structure parameter of higher specific speed centrifugal pump in the blade appropriate design at flanging impeller outlet, improve centrifugal pump Performance and running in stability.

Accompanying drawing explanation

Fig. 1 is the plane figure of the embodiment of the present invention.

Fig. 2 is the axial plane figure of the embodiment of the present invention.

Fig. 3 is that the present invention implements impeller blade schematic diagram.

Fig. 1: β₂₁Blade exit installation angle, β₂₂Lower blade exit installation angle,Blade cornerite,Lower blade Cornerite.

Fig. 2: D₀Impeller inlet equivalent diameter, D₂Impeller outlet diameter, b₂₁Blade exit width, b₂₂Lower blade Exit width, S₂₁Blade exit thickness, S₂₂Lower blade exit thickness.

Fig. 3: 1 impeller blade, 2 impeller lower blades, the arc length that between the upper and lower blade of l, exit is corresponding.

Detailed description of the invention

Design requires: design conditions flow is 0.096764 cube of meter per second, and design conditions lift is 60 meters, rotating speed is 2900 turns/ Second, g takes 10 meters/square metre, and the number of blade takes 4 pieces.

The numerical value of impeller structure parameter: D can be obtained according to data above₀=170mm；D₂=390mm；β₂₁=21 °；β₂₂=21 °；b₂₁=10mm；b₂₂=7mm；S₂₁=7mm；S₂₂=6mm；

In the design process, the selection of other coefficient needs to carry out coefficient according to concrete practical situation and chooses, and the spiral case such as impeller is joined Number needs to select according to the actual motion of pump.

Above, by the present invention with reference to illustrating that embodiment is made, but the present invention is not limited to above-described embodiment, also wraps Containing the other embodiments in the range of present inventive concept or variation.

Claims (8)

1. the method for designing of higher specific speed centrifugal pump impeller port of export edge folding blades structure in a kind, it is characterised in that: design from During heart pump impeller blade, the impeller blade port of export uses layering folded edges；Wherein impeller inlet equivalent diameter D₀Determined by following formula:

$D_0=\left\{\begin{array}{c}(0.4n^{-0.8}{Q}^{0.15}{H}^{0.45}+0.05H)\sqrt[3]{\frac{Q}{n}},\left(H\≤50\right)\\ (0.84n^{0.4}{Q}^{0.25}{H}^{-0.3}+50H^{-1.21}+4.5)\sqrt[3]{\frac{Q}{n}},\left(H>50\right)\end{array}\right.$

In formula:

D₀Impeller inlet equivalent diameter, m；

Q flow, m³/s；

H lift, m；

N rotating speed, rev/min.

The method for designing of a kind of middle higher specific speed centrifugal pump impeller port of export edge folding blades structure the most as claimed in claim 1, it is special Levy and be: impeller blade entrance width b₁Determined by below equation:

$b_1=\left\{\begin{array}{c}0.5Q^{0.5}{H}^{-0.25}-\frac{1.1}{n}{H}^{0.5},(H\≤50)\\ \frac{-0.0072nQ}{H}+1.12Q^{0.5}{H}^{-0.25}-\frac{24}{n}{H}^{0.5},(H>50)\end{array}\right.$

In formula:

b₁Impeller blade entrance width, m；

N rotating speed, rev/min；

Q flow, m³/s；

H lift, m.

A kind of middle high ratio the most as claimed in claim 1 leaves the method for designing of heart pump speed impeller outlet end edge folding blades structure, and it is special Levy and be: impeller outlet diameter D₂Determined by following formula formula:

$D_2=\left\{\begin{array}{c}49.5\left(1.3Z^{0.04}-1.1\right)\left(0.0002H+0.88\right)n^{-0.83}{Q}^{-0.1}{H}^{0.375},\left(H\≤50\right)\\ 49.5\left(0.016Z+0.934\right)\left(0.06932InH+0.72\right)n^{-0.83}{Q}^{-0.1}{H}^{0.375},\left(H>50\right)\end{array}\right.$

In formula:

D₂Impeller outlet diameter, m；

The Z number of blade, piece；

N rotating speed, rev/min；

Q flow, m³/s；

H lift, m.

The method for designing of a kind of middle higher specific speed centrifugal pump impeller port of export edge folding blades structure the most as claimed in claim 1, it is special Levy and be: angle beta is laid in impeller blade outlet₂Determined by below equation:

A angle beta is laid in the outlet of () impeller flanging blade₂₁Determined by below equation:

${\mathrm{\β}}_{21}=\left\{\begin{array}{c}H(0.47+4.5\frac{Z}{H}-0.13Z),(H\≤50)\\ H(0.8+4.2\frac{Z}{H}-0.16Z+0.0002),(H>50)\end{array}\right.$

B angle beta is laid in the outlet of () impeller flanging lower blade₂₂Determined by below equation:

${\mathrm{\β}}_{22}=\left\{\begin{array}{c}H(1.4Z^{0.04}-0.11)(0.5+4.7\frac{Z}{H}-0.11Z),(H\≤50)\\ H(0.0003H+0.9)(0.85+4.5\frac{Z}{H}+0.006H-0.16Z),(H>50)\end{array}\right.$

In formula:

β₂₁Blade outlet laying angle, °；

β₂₂Lower blade outlet laying angle, °；

H lift, m；

The Z number of blade, piece.

The method for designing of a kind of middle higher specific speed centrifugal pump impeller port of export edge folding blades structure the most as claimed in claim 1, it is special Levy and be: impeller blade exit width b₂Determined by below equation:

(a) impeller flanging blade exit width b₂₁Determined by below equation:

$b_{21}=0.0057(-0.005D_2^2+0.03D_2+0.987)n^{0.5}{Q}^{0.5}{H}^{-0.5}$

(b) impeller flanging lower blade exit width b₂₂Determined by below equation:

$b_{22}=0.0133(-0.003D_2^2+0.031D_2+0.99)n^{0.5}{Q}^{0.5}{H}^{-0.5}$

In formula:

b₂₁Blade exit width, m；

b₂₁Lower blade exit width, m；

N rotating speed, rev/min；

Q flow, m³/s；

H lift, m.

The method for designing of a kind of middle higher specific speed centrifugal pump impeller port of export edge folding blades structure the most as claimed in claim 1, it is special Levy and be: impeller blade corneriteDetermined by below equation:

(a) impeller flanging blade corneriteDetermined by below equation:

(b) impeller flanging lower blade corneriteDetermined by below equation:

In formula:

Blade cornerite, °；

Lower blade cornerite, °；

D₀Impeller inlet equivalent diameter, m；

D₂Impeller outlet diameter, m.

The method for designing of a kind of middle higher specific speed centrifugal pump impeller port of export edge folding blades structure the most as claimed in claim 1, it is special Levy and be: the arc length size that between the upper and lower blade of impeller flanging, exit is corresponding is determined by below equation:

In formula:

The arc length that between the upper and lower blade of l impeller flanging, exit is corresponding, m；

D₂Impeller outlet diameter, m；

Blade cornerite, °；

Lower blade cornerite, °.

The method for designing of a kind of middle higher specific speed centrifugal pump impeller port of export edge folding blades structure the most as claimed in claim 1, it is special Levy and be: the exit thickness S of impeller blade₂Determined by below equation:

(a) impeller flanging blade exit thickness S₂₁Determined by below equation:

$S_{21}=\frac{-0.05D_0^2+14.21D_0-0.2}{1.3D_0+90}$

(b) impeller flanging lower blade exit thickness S₂₂Determined by below equation:

$S_{22}=-0.55D_0^2+0.13D_0+0.015$

In formula:

S₂₁Impeller flanging blade exit thickness, m；

S₂₂Impeller flanging lower blade exit thickness, m；

D₀Impeller inlet equivalent diameter, m.