Static Discharge Head

Static Discharge Head The static discharge head is the vertical distance measured from the free surface of the hquid in the receiver to the pump centerhne, plus the absolute pressure at the hquid surface. Total static head hf, is the difference between discharge and suction static heads. 

Before installation it is possible to estimate the total discharge head from the static discharge head h,d and the discharge friction head hfd as follows ... 

The total head on the pumps in Fig. 6.13d, c, and /is computed in the same way as described above, except that the total static head is less because the pump has a static suction head—that is, the elevation of the liquid on the suction side reduces the total distance through which the pump must discharge liquid thus the total static head is less. The static suction head is subtracted from the static discharge head to determine the total static head on the pump. 

Figure 6.23a shows a typical piping system with apump operating against a static discharge head. Indicate the total static head (Fig. 6.23b) by a dashed line—in this installation Hts = 110 ft. Since static head is a physical dimension, it does not vary with flow rate and is a constant for all flow rates. Draw the dashed line parallel to the abscissa (Fig. 6.23b). 

Static Discharge Head The static discharge head h,i is the vertical distance measured from the free surface of the liquid in the... 

The terms suction and discharge in the context of heads refer to portions of the system before and after the pumping station, respectively. Static suction lift h( is the vertical distance from the elevation of the inflow liquid level below the pump inlet to the elevation of the pump centerline or eye of the impeller. A lift is a negative head. Static suction head h, is the vertical distance from the elevation of the inflow liquid level above the pump inlet to the elevation of the pump centerline. Static discharge head h is the vertical distance from the centerline elevation of the pump... 

Static discharge head—The vertical distance from the pump centerline to the elevation of the discharge liquid level. 

Static Discharge Head. The vertical elevation from the center line of the pump to the point of free discharge. 

Dynamic Discharge Head. The static discharge head plus dynamic suction lift or minus dynamic suction head. 

DYNAMIC DISCHARGE HEAD - Static discharge head plus friction head plus velocity head. 

TOTAL DYNAMIC HEAD - Dynamic discharge head (static discharge head, plus friction head, plus velocity head) plus dynamic suction lift, or dynamic discharge head minus dynamic suction head. 

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