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Flashcards in nozzles Deck (7)
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1
Q

kinetic energy

A

energy the wter has due to velocity

2
Q

potential energy

A

energy due to height of water above pump or other reference point

3
Q

describe water flowing thru a type a nozzle with a diagram

A

from point a to point b its velocity, kinetic energy increases at the expense of pressure.

4
Q

Formula for nozzle discharge

and formula for relationship between velocity and original pressure

A

L = 2/3 d ² X square root of P (l/min )

v = 14.14 X Sq root of P

5
Q

describe water flowing thru a venturi with diagram

A

water flows then diameter reduces before increasing again, as reduction is gradual there is little turbulance.
velocity and kinetic energy increases at expense of pressure, as diameter increases velocity is lost and pressure increases.
if pressure recovers to close to its former level its possible the pressure at throat of venturi will be lower than atmospheric. drawing in surrounding liguid.

6
Q

formula for jet reaction

A

R = 0.157 P d²

7
Q

describe jet reaction

A

every force equal and opposite force Newtons 3rd law
can power a boat on jet reaction
reaction is at nozzle outlet applying jet to floor, wall makes no difference