--%>

Problem on pressure rise of a water tank

The water level in a tank is about 20 m above the ground. A hose is joined to the bottom of the tank, and the nozzle in the end of the hose is pointed to straight up. The tank is at sea level, and the water surface is open to the environment. In the line leading from the tank to the nozzle is a pump, that rises the pressure of water. If the water jet increases to a height of 27 m from the ground, then find out the minimum pressure rise that is supplied by the pump to the water line.

828_pressure rise.jpg

E

Expert

Verified

Entry and exit losses at the pump and nozzle are neglected since no data is given

The Bernoulli’s equation

P1/δg + V12/2g +z1 = P2/δg + V22/2g +z2 + Losses (L) – (i) 
P1/δg =  pressure head V2/2g =velocity head Z=  height

Assuming an air  density of 1.225 Kg/m3

Pressure at (2) = δa gh
                      = 1.225 x 9.81x 7
                      = 84.12 Pa ( below  atmosphere

P2 =Absolute pressure at (2)  = Atmospheric  pressure – 84.12
                    = 101.325 x 103 – 84.12
                    = 101240.88 Pa
                    = δa g h + PP ( PP = pump pressure , SW= Water density)
                    =1000 x 9.81 x 20x+PP
                    =196200 + PP Pa

P1=Absolute pressure at (1)  = Patm  +  PP + 196200
                                           = 297525 +PP Pa
V1=V2 =0 a very negligible

Substituting  is (1) where δ =δw  = 1000 Kg/ m3 in the density of water
297525 +PP/ 1000g = 101240.88/ 1000g + 27
Solving for PP , it  comes out to be

PP = 68585.88Pa

   Related Questions in Mechanical Engineering

  • Q : Difference between pressure vessel &

    Difference between pressure vessel & column: The Pressure vessels (cylinder or tank) are utilized to store fluids under pressure. If the pressure vessel are design in the form of column to separate the gas at u

  • Q : Causes and consequences of dynamic

    Discuss the causes and consequences of dynamic loading on structures based on two real examples. Support your discussion with proper diagrams or sketches. Your discussion shall include the time and location of the event, type and source of dynamic loa

  • Q : Ergonomics in product design

    Ergonomics: This is concerned with how easy (comfort, complexity) the product is to use by the targeted market. Physical human dimensions must be considered when designing the driver's seating, instruments, and controls in a car. Slight variations bet

  • Q : Difference between PLC and Logic Card

    Difference between PLC and Logic Card: There is technically no difference. Both are logic controller utilized for several applications and in PLC has it's own internal memory (compared to Logic card).

  • Q : Undamped single degree of freedom (a)

    (a) The response for an undamped single degree of freedom system under free vibration is given as where ωn is the natural frequency and A and B are unknown that can be determined from the initial conditions. The response 

  • Q : Mechatronics Define the tem

    Define the tem Mechatronics and what are its elements?

  • Q : Deareator In Thermal Power Plant, Why

    In Thermal Power Plant, Why Deareator is placed at the Height?

  • Q : What is cotter joint Explain what is

    Explain what is meant by the Cotter joint?

  • Q : Diesel Engine What will happen if the

    What will happen if the gasoline is used within the Diesel Engine, whether the Siesel Engine will work or not?

  • Q : Safety in Product design specification

    Safety: The specifications should state the possible abuse and misuse the product might be subjected to. Warning labels and instructions on safe operation of the product should be given. The designer can be held accountable for any accidents that migh