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渣漿泵的特性曲線分析

離心泵在一定轉速下的揚程與流量、功率與流量、效率與流量、吸上真空度(或必需汽蝕佘量)與流量的關系曲線，稱為泵的工作特性曲線，它們能反映泵的性能特性。
1.揚程一流量曲線
    由歐拉公式可得無限多葉片假設條件下的理論揚程見式(1-16)。在離心泵中,葉輪葉片的出口角一般小于90°。若以流量為橫坐標揚程為縱坐標，則Hx-Qr為一向下傾斜的直線(圖1-29曲線1)。

由式(1-21)可知，離心泵內有限葉片數條件下的理論揚程為Ht=pHro離心泵的滑移系數與流量無關，即μ為常數.將H1。-Q1(曲線1)上各點縱坐標均乘以μ，由于滑移系數μ的值小于1,即可得到葉片數目有限時離心泵的理論揚程Hr-Qτ關系曲線(曲線2)。因實際液體得到的能頭為H= Ht-Hf-Hsh，故從理論揚程Hr- QT(曲線2)中減去同一流量下對應的摩擦損失Hf,得曲線3,再減去沖擊損失Hsh，就可得到實際揚程與流量的關系H-Qr(曲線4)。
    以H-Qt線(曲線4)上工況點C為例，過C點作水平線與H -q線(曲線8)交于點A,與縱坐標交于點B,AB線段的長度即為C點揚程所對應的泄漏量q。將C點向左平移q得到D,點D即為考慮流量泄漏損失后的工況點。從流量一揚程曲線H一QT的橫坐標數值中減去相應的泄漏量q，就可得到泵的流量一揚程曲線 H - Q線(曲線5)。渣漿泵
    由以上分析可知，H-Q曲線的形狀與葉輪的圓周速度u2、外徑D2和葉片角以及各種阻力損失密切相關。

Characteristic curve analysis of slurry pump

The relationship curves of the head and flow, power and flow, efficiency and flow, and suction vacuum (or necessary cavitation) and flow of a centrifugal pump at a certain speed are called the working characteristic curves of the pump, which can reflect the performance characteristics of the pump.

1. Head flow curve

According to Euler's formula, the theoretical lift of infinite blades under the assumption is shown in formula (1-16). In centrifugal pump, the outlet angle of impeller blade is generally less than 90 °. If the flow is taken as the abscissa and the lift as the ordinate, HX QR is a straight line inclined downward (Fig. 1-29 curve 1).

It can be seen from formula (1-21) that under the condition of limited number of blades in centrifugal pump, the theoretical head is HT = phro, and the slip coefficient of centrifugal pump is independent of flow, i.e., μ is constant. -The longitudinal coordinates of each point on Q1 (curve 1) are multiplied by μ. Since the value of slip coefficient μ is less than 1, the theoretical head hr-q τ relation curve (curve 2) of centrifugal pump with limited number of blades can be obtained. Since the energy head of the actual liquid is h = HT HF sh, the friction loss HF corresponding to the same flow rate is subtracted from the theoretical head hr-qt (curve 2), and then the curve 3 is obtained, and the impact loss SH is subtracted, then the relationship between the actual head and flow h-qr (curve 4) can be obtained.

Take point C on h-qt line (curve 4) as an example, cross point C as horizontal line and H-Q line (curve 8) to point a, and cross point B with ordinate. The length of line AB is the leakage Q corresponding to the lift of point C. Translate point C to the left and Q to get D. point D is the operating point after considering the loss of flow leakage. By subtracting the corresponding leakage Q from the abscissa value of the flow head curve h-qt, the flow head curve H-Q line (curve 5) of the pump can be obtained. Slurry pump

It can be seen from the above analysis that the shape of H-Q curve is closely related to the peripheral velocity U2, outer diameter D2, blade angle and various resistance losses of impeller.