1) The document discusses the impact of a water jet on curved plates at different points of contact. 2) Equations are provided to calculate the force exerted by the jet and work done based on whether the jet hits at the center of a symmetrical plate or tangentially at the end. 3) Additional equations calculate force, work, power, and efficiency when the plate is moving and the jet hits tangentially at the tip.

1. Gandhinagar Institute of Technology
Subject :- Fluid Power Engineering
MECHANICAL ENGINEERING
5th - B : 2
Impact of jet on curved plate
–
Pavan Narkhede [130120119111]
:
Prof. Parth Panchal

2. 1) When the jet strikes at the centre of the symmetrical
blade

3.  The plate is smooth and there is no loss of energy due to impact of
jet.
Force exerted by jet in the direction of jet,
Force exerted by jet on curved fixed plate in vertical direction,
]cos1[
)]cos([)(
][V)water/secofmass(
2
21x





AVF
VVAVF
VF
x
x
xx



sin
]sin0[)(
][)(
2
21
AVF
VAVF
VVAVF
y
y
yyy




4. 2) When jet strikes tangentially at one end of symmetrical
plate

5. 


2180diflectionofAngle
0
]sinsin[)(
)(AV)( 21




y
y
yyy
F
VVAVF
VVF



cos2
)]cos(cos[)(
)(AV)(
2
21
AVF
VVAVF
VVF
x
x
xxx



 Consider a water jet striking on symmetrical curved plate
tangentially at one end as shown in figure.

6. 3) When jet strikes tangentially at one end of unsymmetrical
plate
)(180diflectionofAngle
]sin[sin
]cos[cos
2
2






AVF
AVF
y
x

7. 1) When jet strikes at the centre and plate moving in the direction of
jet.

8. The relative velocity between jet and plate = V – u.
 Force exerted by water jet on moving curved plate
 Work done by the jet on the plate/second
]cos1[)(
)]cos1)()[((
)]cos)(()[(Vplate)thestrikesjetith whichvelocity w(
2






uVAF
uVuVAF
uVuA
x
x
]cos1[)Au(V.
secondmoveddistance
2
 

uDW
Fx

9. 2) When jet strikes tangentially at one of the tips

12. 1) Force exerted by the jet in the direction of motion
2) Work done per unit weight of fluid striking per second
][
,ofany valueTherefore,
][,90If
][,0,90If
][,90,If
211
2
2112
1122
211221
wwrx
wwrx
wrxw
wwrx
VVAVF
VVAVF
VAVFVthen
VVAVFuu









Nm/Kg,][ 21 uVVWD ww 

13. 3) Power developed, P=work done in J/s
4) Blade efficiency or jet efficiency
5) Angle of Deflection
uVVAVP wwr  ][ 211
3
1
211 ][2
V
uVVV wwr
b


)(180 21  

17. Water leaves the nozzle at a velocity with force until it hits the plate, for a
flat plate the force generated is minimum return but maximum force
moving that plate where it has minimal deflection. As the plate curvature
increases the resultant deflection is smoother and less ‘beating’ of the
plate, hence the force returning increases. The angle increase will improve
force.
Newton’s 3rd law explains for every action there is a equal and opposite
reaction and this is proved by the results table where the increase in force
arrow increase’s with the plate’s angle. Please refer to diagram below to
aid my best attempt of an explanation:

18. It is clear the hemisphere is more suitable, followed by the curved plated followed
by the flat plate. By the statements above the oblique plate would have been more
efficient than the flat plate and less efficient than the curved with it’s deflection
angle at 60 degrees.

19. Experiment of impact of jet on curve plate

20. THANK YOU….