渣浆泵串联的解析法

设两台离心泵串联工作，分别由两台泵实测或泵特性曲线上取点得到几组扬程.流量数据.用最小二乘祛回归得到泵的特性方程分别为:
式中的系数a1、b1、a2、b2可由式(1 - 69)计算得到。
    按照两泵串联后的总扬程等于两泵在同一流量时的扬程之和，即Q=Ql=Qll时Hl+ll= Hl+ Hll的原则，有:则两台相同泵串联后的特性方程为:

H=A-BQ2
将其与管路特性方程联立，即可解得系统工作点。多台离心泵串联工作也可按此原则进行计算。

3.复杂管路系统工作点的确定

对于复杂管路系统来说，根据水力特点，并联时管路交叉点的压力相等，总流量等于各支管流量之和；串联时各管段流量相等，总摩阻等于各管段摩阻之和进行叠加。对于交汇及分支管路系统，求解过程如下。

1) 泵在分支管路上工作的装置特性

经过一台泵(或几台泵申联、并联)将油品同时输往一处或几处时，要采取分支管路来工作，如图1- 48(a)所示。油品由管1经过泵后再沿管2和管3分别输送到两油罐内。三个油罐中液面对于泵轴线的标高差为z1、z2和z3。

(1) 图解法。

画出吸入管路特性(h-Q)1以及排出管路的特性(h-Q)2和(h-Q)3。因管2和管3是并联工作,需按并联相加得管路特性(h-Q)2+3。然后再和(h-Q)1串联相加，得到整个管路系统的总管路特性(h-Q)at ,它和泵的性能曲线H-Q相交于M点，即为分支管路的工作点。

M点相应的流量Qw就是管1中的流量Q。为确定管2和管3中的流量，过M点作垂线与管路特性(h-Q)2+3相交于A点,从A点引水平线与(h Q)2相交于点2，与(h-Q)3相交于点3，则点2和点3相应的流量Q2和Q3即为管2和管3中的流量,并且Qm=Qa=Q2+Q3=Q1。

(2) 解析法。

由泵实测或泵特性曲线上取点得到几组扬程、流量数据,用最小二乘法回归得到泵的特性方程为H=a-bQ2，系数a、b可由式(1- 69)计算得到。
管路1的特性方程为:

管路2的特性方程为:
                        h2=z2+k2Q2

管路3的特性方程为:

h3=z3+k3Q3
管路2和管路3先并联然后与管路1串联，根据管道并联原则有:
h2=h3, Q=Q1=Q2 + Q3
管路总特性为:
h=h1 +h2或h=h1 + h3

对于系统来说:

h= H,Q1 =Q渣浆泵厂家

解方程组即可求得Q1、Q2、Q3。

Analytical method of slurry pump in series
Two centrifugal pumps are designed to work in series, and several groups of head and flow data are obtained from the measured data of two pumps or the points on the pump characteristic curve. The characteristic equations of pumps are obtained by least square regression
The coefficients A1, B1, A2 and B2 in the formula can be calculated by formula (1-69).
According to the principle that the total head of two pumps in series is equal to the sum of the heads of two pumps at the same flow, that is, when q = QL = QLL, HL + ll = HL + HL, the characteristic equation of two pumps in series is as follows:
H=A-BQ2
The working point of the system can be obtained by combining it with the characteristic equation of pipeline. Several centrifugal pumps in series can also be calculated according to this principle.
3. Determination of working point of complex pipeline system
For the complex pipeline system, according to the hydraulic characteristics, the pressure at the crossing point of the pipeline is equal in parallel, and the total flow is equal to the sum of the flow of each branch pipe; the flow of each pipe section is equal in series, and the total friction is equal to the sum of the friction of each pipe section for superposition. For the intersection and branch pipeline system, the solution process is as follows.
1) Device characteristics of pump working on branch pipeline
When oil products are transported to one or several places at the same time through one pump (or several pumps applying for connection or parallel connection), branch pipeline shall be adopted for operation, as shown in Fig. 1-48 (a). The oil is pumped by tube 1 and then transported to two oil tanks along tube 2 and tube 3 respectively. The elevation difference of the three oil tanks to the pump axis is Z1, Z2 and Z3.
(1) Graphic method.
Draw the characteristics of suction line (H-Q) 1 and discharge line (H-Q) 2 and (H-Q) 3. Because tube 2 and tube 3 work in parallel, it is necessary to add the characteristics (H-Q) 2 + 3 in parallel. Then add (H-Q) 1 in series to get the total pipeline characteristic (H-Q) at of the whole pipeline system. It intersects the performance curve H-Q of the pump at point m, which is the working point of the branch pipeline.
The corresponding flow QW at point m is the flow Q in tube 1. In order to determine the flow in pipe 2 and pipe 3, make a vertical line through point m to intersect with the pipeline characteristic (H-Q) 2 + 3 at point a, lead the horizontal line from point a to intersect with (H q) 2 at point 2, and intersect with (H-Q) 3 at point 3, then the corresponding flow Q2 and Q3 at point 2 and point 3 are the flow in pipe 2 and pipe 3, and QM = QA = Q2 + Q3 = Q1.
(2) Analytical method.
Several groups of head and flow data are obtained from the measured pump or the points on the pump characteristic curve. The characteristic equation of the pump is h = a-bq2 by least square regression. The coefficients a and B can be calculated by formula (1-69).
The characteristic equation of pipeline 1 is as follows:
The characteristic equation of pipeline 2 is:
H2=z2+k2Q2
The characteristic equation of pipeline 3 is as follows:
H3=z3+k3Q3
Pipeline 2 and pipeline 3 are connected in parallel and then in series with pipeline 1. According to the principle of pipeline parallel connection, they are as follows:
h2=h3, Q=Q1=Q2 + Q3
The general characteristics of the pipeline are:
H = H1 + H2 or H = H1 + H3
For the system:
H = h, Q1 = q slurry pump manufacturer
Q1, Q2 and Q3 can be obtained by solving the equations.