Analysis: A centrifugal pump converts driver energy to kinetic energy in a liqui

Question

Analysis:

A centrifugal pump converts driver energy to kinetic energy in a liquid by accelerating the fluid to the outer rim of an impeller. The amount of energy given to the liquid corresponds to the velocity at the edge or vane tip of the impeller. The faster the impeller revolves or the bigger the impeller, then the higher the velocity of the liquid at the vane tip and the greater the energy imparted to the liquid. Creating a resistance to the flow controls the kinetic energy of a liquid coming out of an impeller. The first resistance is created by the pump volute (casing), which catches the liquid and slows it down. When the liquid slows down in the pump casing, some of the kinetic energy is converted to pressure energy. It is the resistance to the pump’s flow that is read on a pressure gauge attached to the discharge line. A pump does not create pressure, it only creates flow. Pressure is a measurement of the resistance to flow.

Friction head is the head required to overcome the resistance to flow in the pipe and fittings. It depends on the size, condition and type of pipe; the number and type of pipe fittings; flow rate; and nature of the liquid. Velocity head is the energy of a liquid as a result of its motion at some velocity (V). It is the equivalent head in feet through which the water would have to fall to acquire the same velocity or, in other words, the head necessary to accelerate the water.

power outlet and inlet, velocity, torque, pressure change and impeller efficiency are calculated in the table

Analysis: Explain the significance of the results along with the reliability of the data.

out Opening | hin | About | Ap | V in KPam/s 294 225 156 68 19 0 0 20 40 60 80 100 0.50 0.14 0.28 0.37 0.95 0.30 0.23 0.16 0.70 0.20 625 1,750 3,500 39.9 4,625 11,875 7.125279,300 5 214,13014 148,96028 52.72565,170 37 135.38 18,62095 5.5 6.8 6.8 6.9 6.9 19.95

Explanation / Answer

From the table of the result obtained from the calculation we can say that if opening is 20% that means that we are not utilising the pump with given capcitu so it is not going to give the good efficiency.

So from the table we can say that the efficiency is high in the case of 100% opening which means we are utilising full capacity of the pump so we are getting full efficiency.

And we talk about the velocity of the water at outlet which is indirectly affected by the pressure drop , if the pressure drop is high that means pressure energy is converted into the kinetic energy.

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.