CN106897512A - A kind of method for designing of the bell-shaped suction box of pumping plant - Google Patents

Abstract

The invention belongs to the application field of pumping plant, it is related to a kind of method for designing of the bell-shaped suction box of pumping plant.Using the design formula of the main geometric parameters of bell-shaped suction box of the invention, including：Bell-shaped suction box height H_w, bell-shaped suction box suction chamber back wall distance X_T, bell-shaped suction box entrance width B_j, bell-shaped suction box length X_L, bell-shaped suction box oviduct height H_L, bell-shaped suction box water guide cone base diameter D_z, the top taper angle α of bell-shaped suction box inducer, the lower sideline angle of inclination beta of bell-shaped suction box, the outlet diameter D of bell-shaped suction box oviduct, the height H of bell-shaped suction box water guide cone₁, bell-shaped suction box oviduct inlet diameter D_LDeng the bell-shaped suction box of pumping plant can to a certain extent improve Inlet flow pattern, greatly reduce the hydraulic loss of water inlet flow channel, so as to improve the stability and high efficiency of pumping station operation.

Description

A kind of method for designing of the bell-shaped suction box of pumping plant

Technical field

The present invention is to be related to the application field of pumping plant, more particularly to a kind of method for designing of bell-shaped suction box.

Background technology

Bell-shaped suction box early stage is mainly used in some large-scale irrigation and drainage pumping stations of foreign countries, afterwards just in the large-scale of China Gradually applied in pumping plant construction.Bell-shaped suction box is main by several portions such as inducer, suction chamber, water guide cone and oviduct Divide and constitute, its Main Function is after current enter inducer from intake pool, oviduct import to be directed water flow towards by suction chamber Surrounding, then water pump vane room is entered by the passage between oviduct and water guide cone.Additionally, in order to farthest reduce bell The hydraulic loss of water inlet flow channel, the design of inducer is generally rectangle, and water suction volute casing is generally in the plane scroll casing shape.

Because bell-shaped suction box height is lower than elbow inlet passage, while there is larger width and rear wall space, So as to current can be made to enter oviduct from surrounding, therefore pump house bottom plate heights can be raised.In addition, its structure is relatively simple, apply Work builds more more convenient than ancon-form flow channel, therefore substantially improves flow condition, while reducing construction cost, this is for big mouth Footpath vertical pump is very economical rationality using bell-shaped suction box, has weight especially for the poor pumping plant address of geological conditions The meaning wanted.Further, since need the amount of concrete of filling smaller between runner and runner, therefore bell-shaped suction box is to section About construction investment, quickening construction progress etc. all have obvious advantage, in the future as the gradually increase of vertical water pump bore, use The pumping plant of bell-shaped suction box also will be as a kind of trend.

A kind of optimization of bell-shaped suction box is disclosed in the Chinese invention patent that Patent No. 201510660430.0 Method for designing, it provides specific design, it is ensured that the designing quality of water inlet flow channel, this stabilization for pumping station operation Property and high efficiency have highly important effect.However, it does not provide the inlet height of bell-shaped suction box, inducer top gradually The specific perfect design side such as contracting angle, inducer lower sideline inclination angle, oviduct inlet diameter, flow channel length and water guide cone height Method.A kind of excellent bell-shaped suction box of hydraulic performance is disclosed in the patent that Patent No. 201420626615.0, it is explained Stated bell-shaped suction box design basic thought, there is provided the computational methods of its main geometric parameters, however, its also without Provide the specific design formula of water inlet flow channel inducer top taper angle and oviduct height.

The content of the invention

For the weak point present on, the present inventor has invented a kind of design side of the bell-shaped suction box of pumping plant Method.The Exact Design scheme of bell-shaped suction box main geometric parameters is not only gived, also improves the reliability of pumping station operation And stability, such that it is able to extend the service life and maintenance cycle of water inlet flow channel.

The effect of bell-shaped suction box is, in order to reduce the hydraulic loss of Inlet flow pattern as far as possible, therefore suction chamber to be set Meter requires higher.Traditional design is its hydraulic loss of relative reduction, is examined for its stability, security and economy Consider less, and these are all exactly the places that can not ignore in Design of Pump Station, therefore, design is further optimized to it and is seemed It is particularly important.The present invention is above-mentioned in order to solve the problems, such as, gives the design side of the bell-shaped suction box different from traditional design Method.Mainly by controlling oviduct, water guide cone and the main geometric parameters of inducer, the operation effect of pumping plant is improved with this The stability and security of rate and enhancing pumping plant, finally increase economic efficiency.According to above-mentioned steps, a kind of practicality can be obtained Preferable bell-shaped suction box main geometric parameters method for designing.By the several important geometric parameters for improving bell-shaped suction box Number, including bell-shaped suction box height H_w, bell-shaped suction box suction chamber back wall distance X_T, bell-shaped suction box import it is wide Degree B_j, bell-shaped suction box oviduct height H_L, bell-shaped suction box water guide cone top diameter d, the length of bell-shaped suction box Degree X_L, bell-shaped suction box inducer inlet height H_j, the water guide cone base diameter D of bell-shaped suction box_z, bell feed water flow The outlet diameter D of road oviduct, the inlet diameter D of bell-shaped suction box oviduct_L, the top of shape water inlet flow channel inducer is tapered Angle α, the lower sideline angle of inclination beta of bell-shaped suction box, the height H of bell-shaped suction box water guide cone₁, bell-shaped suction box suction chamber Height H₂, bell-shaped suction box turns to the plane spiral case sweep r of section, waterpower in water inlet flow channel reduced as far as possible and is damaged Lose, the high efficiency and stability of pumping plant are improved with this.

The technical scheme used to realize the above to obtain purpose is：

(1) the height H of bell-shaped suction box_w, bell-shaped suction box suction chamber back wall distance X_T, bell-shaped suction box enters Mouth width B_j, bell-shaped suction box oviduct height H_L, bell-shaped suction box water guide cone top diameter d computing formula point It is not：

In formula：

H_wThe height of-bell-shaped suction box, rice；

X_TThe suction chamber back wall distance of-bell-shaped suction box, rice；

B_jThe entrance width of-bell-shaped suction box, rice；

H_LThe oviduct of-bell-shaped suction box highly, rice；

The top diameter of d-bell-shaped suction box water guide cone, rice；

n_sThe specific speed of-pumping plant pump；

The lift of H-pumping plant pump, rice；

The rotating speed of n-pumping plant pump, rev/min；

The flow of Q-pumping plant pump, rice³/ the second；

D₀The impeller diameter of-pumping plant pump, rice.

(2) the length X of bell-shaped suction box_L, bell-shaped suction box inducer inlet height H_jComputing formula it is as follows：

In formula：

X_L- bell-shaped suction box length, rice；

H_jThe inlet height of-bell-shaped suction box inducer, rice；

The rotating speed of n-pumping plant pump, rev/min；

n_sThe specific speed of-pumping plant pump.

(3) the water guide cone base diameter D of bell-shaped suction box_z, bell-shaped suction box oviduct outlet diameter D calculating Formula is as follows：

D=-8.71e^-13n_s ⁴+3.412e^-9n_s ³-4.384e^-6n_s ²+0.00167n_s+1.85 (9)

In formula：

D_zThe water guide cone base diameter of-bell-shaped suction box, rice；

The outlet diameter of D-bell-shaped suction box oviduct, rice；

n_sThe specific speed of-pumping plant pump；

The lift of H-pumping plant pump, rice；

The rotating speed of n-pumping plant pump, rev/min.

(4) the inlet diameter D of bell-shaped suction box oviduct_LComputing formula it is as follows：

In formula：

D_LThe inlet diameter of-bell-shaped suction box oviduct, rice；

D_zThe water guide cone base diameter of-bell-shaped suction box, rice；

The outlet diameter of D-bell-shaped suction box oviduct, rice.

(5) computing formula of the top taper angle α of bell-shaped suction box inducer is as follows：

In formula：

The top taper angle of α-bell-shaped suction box inducer, degree；

D₀The impeller diameter of-pumping plant pump, rice.

(6) computing formula of the lower sideline angle of inclination beta of bell-shaped suction box is as follows：

β=17.48sin (0.1672 α+3.519)+6.289sin (0.2955 α+9.729) (12)

In formula：

The lower sideline inclination angle of β-bell-shaped suction box, degree；

The top taper angle of α-bell-shaped suction box inducer, degree.

(7) the height H of bell-shaped suction box water guide cone₁Computing formula it is as follows：

In formula：

H₁The height of-bell-shaped suction box water guide cone, rice；

D₀The impeller diameter of-pumping plant pump, rice；

The lift of H-pumping plant pump, rice；

The rotating speed of n-pumping plant pump, rev/min.

(8) the height H of bell-shaped suction box suction chamber₂Computing formula it is as follows：

In formula：

H₂The height of-bell-shaped suction box suction chamber, rice；

D₀The impeller diameter of-pumping plant pump, rice；

H₁The height of-bell-shaped suction box water guide cone, rice.

(9) bell-shaped suction box turns to the plane spiral case sweep r of section

R=-2.019e^-5Q⁴+0.0003783Q³+0.001813Q²-0.02298Q+1.633 (15)

In formula：

R-bell-shaped suction box turns to the plane spiral case sweep of section, rice；

The flow of Q-pumping plant pump, rice³/ the second.

The main geometric parameters of the bell-shaped suction box of the accurate pumping plant of comparatively perfect can be obtained by above step Method for designing.

The oviduct and water guide element of a cone of the bell-shaped suction box use 1/4 elliptic arc.

Beneficial effects of the present invention are：

Design of the present invention carries out one to parameters such as the width of inducer, height, top taper angle and lower sideline inclination angles The adjustment of certainty ratio, reduces inducer to the collision loss between oviduct, and Inlet flow pattern is substantially improved to a certain extent Stability.In addition, optimizing design by the physical dimension to water guide cone and oviduct to reduce the whirlpool in water inlet flow channel Flow and along journey hydraulic loss, and also make the flow-shape of delivery port relatively more steady, so as to improve the steady of pumping station operation Qualitative, high efficiency and security.

Brief description of the drawings

Fig. 1 is the profile of the bell-shaped suction box of pumping plant.

Fig. 2 is the plan of the bell-shaped suction box of pumping plant.

Specific implementation method

The present invention is further described with reference to the accompanying drawings and detailed description.

The present invention determines a kind of main geometric parameters of the bell-shaped suction box of pumping plant by following formula, wraps Include：Bell-shaped suction box height H_w, bell-shaped suction box suction chamber back wall distance X_T, bell-shaped suction box entrance width B_j, clock Shape water inlet flow channel length X_L, bell-shaped suction box oviduct height H_L, bell-shaped suction box water guide cone base diameter D_z, clock The top taper angle α of shape water inlet flow channel inducer, the lower sideline angle of inclination beta of bell-shaped suction box, bell-shaped suction box oviduct The height H of outlet diameter D, bell-shaped suction box water guide cone₁, bell-shaped suction box oviduct inlet diameter D_L, bell feed water flow The height H of road suction chamber₂, bell-shaped suction box inducer inlet height H_j, bell-shaped suction box water guide cone top diameter d Deng.Additionally, oviduct and water guide element of a cone use 1/4 elliptic arc.

This embodiment be the design conditions flow Q of given pumping plant pump, design conditions lift H, design conditions rotating speed n, The impeller diameter D of pumping plant pump₀A kind of main geometric parameters of the bell-shaped suction box of pumping plant are calculated etc. several parameters：

D=-8.71e^-13n_s ⁴+3.412e^-9n_s ³-4.384e^-6n_s ²+0.00167n_s+1.85 (9)

β=17.48sin (0.1672 α+3.519)+6.289sin (0.2955 α+9.729) (12)

R=-2.019e^-5Q⁴+0.0003783Q³+0.001813Q²- 0.02298Q+1.633 (15) is entered with the present invention As a example by mouth section：

Work as Q=3m³/s,B_j=4.32m, H_jDuring=0.992m,

ByCan obtain, v=0.7m/s,

By Darcy formula：Can obtain,

Table look-up：ε=0.1, i.e. H_f=0.0025m, this parthydraulic loss is far smaller than the water that Conventional wisdom method is given Power is lost,

In formula：H_f- partially along journey hydraulic loss, m；

ε-coefficient of partial resistance；

Mean flow rate in v-pipeline on effective cross-section, m/s；

G-acceleration of gravity, m/s²。

Therefore, the inducer parthydraulic loss that the present invention is given more may be used than the hydraulic loss that Conventional wisdom method draws Lean on, other each several part hydraulic loss algorithms are similar to therewith.

The present invention using relatively accurate formula to a kind of pumping plant with the main geometric parameters of bell-shaped suction box carry out Design, mainly reduces the effect of its internal hydraulic loss to reach by improving the relevant parameter of bell-shaped suction box.This is not The stability and high efficiency of pumping station operation are improve only, its maintenance cycle is also reduced, this has for large-scale hydraulic engineering building Highly important meaning.

The above-mentioned detailed description made with reference to embodiment for patent of the present invention, but the reality the invention is not limited in more than Example is applied, also including the other embodiment and variation in the range of present inventive concept.

Claims (10)

1. a kind of method for designing of the bell-shaped suction box of pumping plant, it is characterised in that the bell-shaped suction box it is main several What parameter includes：The height H of bell-shaped suction box_w, bell-shaped suction box suction chamber back wall distance X_T, bell-shaped suction box enters Mouth width B_j, bell-shaped suction box oviduct height H_L, bell-shaped suction box water guide cone top diameter d, computing formula is such as Under：

$\begin{array}{c}{H}_w=2.702e^5\sin \left(\frac{{n_s}^2{H}^{\frac{3}{2}}}{1909.215n^2}\right)+4.237e^6\cos \left(\frac{{n_s}^2{H}^{\frac{3}{2}}}{1909.215n^2}\right)-5.407e^5\sin \left(\frac{{n_s}^2{H}^{\frac{3}{2}}}{3818.429n^2}\right)\\ -1.697e^7\cos \left(\frac{{n_s}^2{H}^{\frac{3}{2}}}{3818.429n^2}\right)+1.274e^7\end{array}---\left(1\right)$

$X_T=-\frac{102.41e^{-10}{n}^3{Q}^{\frac{3}{2}}}{H^{\frac{9}{4}}}+\frac{15.108e^{-6}{n}^{2}Q}{H^{\frac{3}{2}}}-\frac{0.77n\sqrt{Q}}{H^{\frac{3}{4}}}+3.422---\left(2\right)$

$B_j=0.05622{D_0}^{7.11}\·e^{-0.006932{D_0}^{8.11}}---\left(3\right)$

$H_L=0.8069e^{-\frac{0.0056n\sqrt{Q}}{H^{\frac{3}{4}}}}+0.4457e^{-\frac{28.44e^{-5}n\sqrt{Q}}{H^{\frac{3}{4}}}}---\left(4\right)$

$d=-0.5233{\left(\frac{1.672Q^2-61.09Q+618}{Q^2-33.73Q+308.8}\right)}^2+3.459\left(\frac{1.672Q^2-61.09Q+618}{Q^2-33.73Q+308.8}\right)-4.456---\left(5\right)$

In formula：

H_wThe height of-bell-shaped suction box, rice；

X_TThe suction chamber back wall distance of-bell-shaped suction box, rice；

B_jThe entrance width of-bell-shaped suction box, rice；

H_LThe oviduct of-bell-shaped suction box highly, rice；

The top diameter of d-bell-shaped suction box water guide cone, rice；

n_sThe specific speed of-pumping plant pump；

The lift of H-pumping plant pump, rice；

The rotating speed of n-pumping plant pump, rev/min；

The flow of Q-pumping plant pump, rice³/ the second；

D₀The impeller diameter of-pumping plant pump, rice.

2. a kind of method for designing of the bell-shaped suction box of pumping plant according to claim 1, it is characterised in that the clock The geometric parameter of the shape water inlet flow channel also length X including bell-shaped suction box_L, bell-shaped suction box inducer inlet height H_j, Computing formula is as follows：

$X_L=114.1{\left(\frac{400}{n}\right)}^{0.09093}-113.6---\left(6\right)$

$H_j=\frac{-0.008529{n_s}^2+2049n_s-0.5955}{{n_s}^2+309.9n_s+16.76}---\left(7\right)$

In formula：

X_L- bell-shaped suction box length, rice；

H_jThe inlet height of-bell-shaped suction box inducer, rice；

The rotating speed of n-pumping plant pump, rev/min；

n_sThe specific speed of-pumping plant pump.

3. a kind of method for designing of the bell-shaped suction box of pumping plant according to claim 1, it is characterised in that the clock The geometric parameter of the shape water inlet flow channel also water guide cone base diameter D including bell-shaped suction box_z, bell-shaped suction box oviduct Outlet diameter D, computing formula is as follows：

$D_z=\frac{\frac{{n_s}^4{H}^3}{106.25n^4}-\frac{4.585{n_s}^2{H}^{\frac{3}{2}}}{n^2}+618}{\frac{{n_s}^4{H}^3}{177.489n^4}-\frac{2.532{n_s}^2{H}^{\frac{3}{2}}}{n^2}+308.8}---\left(8\right)$

D=-8.71e^-13n_s ⁴+3.412e^-9n_s ³-4.384e^-6n_s ²+0.00167n_s+1.85 (9)

In formula：

D_zThe water guide cone base diameter of-bell-shaped suction box, rice；

The outlet diameter of D-bell-shaped suction box oviduct, rice；

n_sThe specific speed of-pumping plant pump；

The lift of H-pumping plant pump, rice；

The rotating speed of n-pumping plant pump, rev/min.

4. a kind of method for designing of the bell-shaped suction box of pumping plant according to claim 3, it is characterised in that the clock The geometric parameter of the shape water inlet flow channel also inlet diameter D including bell-shaped suction box oviduct_L, design formula is：

$D_L=-9.086+0.2301sin\left(0.9147{\mathrm{\πD}}_{z}D\right)+11.63e^{-{\left(3.365e^{-5}D\right)}^2}---\left(10\right)$

In formula：

D_LThe inlet diameter of-bell-shaped suction box oviduct, rice；

D_zThe water guide cone base diameter of-bell-shaped suction box, rice；

The outlet diameter of D-bell-shaped suction box oviduct, rice.

5. a kind of method for designing of the bell-shaped suction box of pumping plant according to claim 1, it is characterised in that the clock The geometric parameter of shape water inlet flow channel also includes the top taper angle α of bell-shaped suction box inducer, and design formula is：

$\mathrm{\α}=6.68e^{-{\left(\frac{D_0-2.577}{0.09997}\right)}^2+14}+28.01e^{-{\left(\frac{D_0-1.952}{0.593}\right)}^2}---\left(11\right)$

In formula：

The top taper angle of α-bell-shaped suction box inducer, degree；

D₀The impeller diameter of-pumping plant pump, rice.

6. a kind of method for designing of the bell-shaped suction box of pumping plant according to claim 5, it is characterised in that the clock The geometric parameter of shape water inlet flow channel also includes the lower sideline angle of inclination beta of bell-shaped suction box, and design formula is：

β=17.48sin (0.1672 α+3.519)+6.289sin (0.2955 α+9.729) (12)

In formula：

The lower sideline inclination angle of β-bell-shaped suction box, degree；

The top taper angle of α-bell-shaped suction box inducer, degree.

7. a kind of method for designing of the bell-shaped suction box of pumping plant according to claim 1, it is characterised in that the clock The geometric parameter of the shape water inlet flow channel also height H including bell-shaped suction box water guide cone₁, design formula is：

$H_1=-16.99+20.72D_0-\frac{{n_s}^2{H}^{\frac{3}{2}}}{23.447n^2}-5.813{D_0}^2-\frac{D_0{n_s}^2{H}^{\frac{3}{2}}}{1018.54n^2}+\frac{{n_s}^4{H}^3}{19404.07n^4}---\left(13\right)$

In formula：

H₁The height of-bell-shaped suction box water guide cone, rice；

D₀The impeller diameter of-pumping plant pump, rice；

The lift of H-pumping plant pump, rice；

The rotating speed of n-pumping plant pump, rev/min.

8. a kind of method for designing of the bell-shaped suction box of pumping plant according to claim 7, it is characterised in that the clock The geometric parameter of the shape water inlet flow channel also height H including bell-shaped suction box suction chamber₂, design formula is：

$\begin{array}{c}{H}_2=-1.301+4.214(114.1{D_0}^{0.09093}-113.6)-15.29H_1-1.268{(114.1{D_0}^{0.09093}-113.6)}^2\\ +8.522H_1(114.1{D_0}^{0.09093}-113.6)-13.76{H_1}^2\end{array}---\left(14\right)$

In formula：

H₂The height of-bell-shaped suction box suction chamber, rice；

D₀The impeller diameter of-pumping plant pump, rice；

H₁The height of-bell-shaped suction box water guide cone, rice.

9. a kind of method for designing of the bell-shaped suction box of pumping plant according to claim 1, it is characterised in that the clock The geometric parameter of shape water inlet flow channel also includes that bell-shaped suction box turns to the plane spiral case sweep r of section, and design formula is：

R=-2.019e^-5Q⁴+0.0003783Q³+0.001813Q²-0.02298Q+1.633 (15)

In formula：

R-bell-shaped suction box turns to the plane spiral case sweep of section, rice；

The flow of Q-pumping plant pump, rice³/ the second.

10. the method for designing of the bell-shaped suction box of a kind of pumping plant according to claim 1, it is characterised in that described The oviduct and water guide element of a cone of bell-shaped suction box use 1/4 elliptic arc.