Question

3.1) Water at 15° (v = 1.13 x 10 m/s) is pumped from reservoir A (surface elevation 20 m) to reservoir B (surface elevation 50 m), as shown in Figure 2. Suction pipe and the discharge pipe information is given in Table 4 and flow into reservoir Bis controlled by two gate valves and entry coefficient loss is given in the sketch. Pump characteristics are given in Table 5. a) What is the flow rate? b) Find the power required to drive the pump (22) W. Elev. 50 m Two Gate Valves fully open) W. Elev. 20 m Check Valve (swing type) K - 1.0 Figure 2 B Suction & delivery pipe diameter (mm) 250 Suction & delivery pipe length (m) 1200 Pipes surface roughness (mm) 0.26 Table 5: Pump characteristics Q(US) Hm) 40 39 36 0 10 20 30 40 50 (5 0 52 74 77 67 47 一 188

Answer 1

To find the flow rate and power required to drive the pump, we need to analyze the given information. The water is being pumped from reservoir A to reservoir B, with a surface elevation difference of 50 m. The pump characteristics are given in Table 5.

a) To find the flow rate, we need to determine the head loss and the pump head. The head loss consists of three components: the friction loss in the suction pipe, the friction loss in the discharge pipe, and the entry coefficient loss.

To calculate the friction loss in the pipes, we need to know the diameter, length, and surface roughness of both the suction and discharge pipes. These values are given as 250 mm and 1200 m, and 0.26 mm respectively.

The entry coefficient loss is given in the sketch, but it's not provided in the question. Without this information, we cannot calculate the flow rate accurately.

b) To find the power required to drive the pump, we need to use the pump characteristics from Table 5. The pump characteristics provide the flow rate (Q) and the total head (Hm) at different points on the pump curve.

Unfortunately, the table you provided for pump characteristics is not clear and seems to be incomplete. Without accurate pump characteristics, we cannot determine the power required to drive the pump.

In summary, we are unable to calculate the flow rate and power required to drive the pump accurately due to missing or incomplete information in the question.