Page 169 - Mechanical Engineer's Data Handbook

158 MECHANICAL ENGINEER'S DATA HANDBOOK

Jet on angled plate
F=pAP(l-cost?) in direction of VI
For e=90", F=~AV,
For t?=180°, F=2pAV2.

V 't'

Moving flat plate

Moving angled plate
Example

U
If r= -0.4, t?= 170°, V= 10 m s- I, A =4 cm2 (=4 x
Angled plate. e= 180' V
10-4m3) and p=lOOOkgm-'. Then P=lOOox
4.5.2 Jet on moving plates 4 x x lo3 x 0.4(1-0.4)(1 -COS 170°)=
190.5 watts
Jet on apat plate
Jet on jixed curved vane
F=pAV(V- U)
where: U =plate velocity. In the x direction: F,= pA V2(cos t?, +cos e,)
In the y direction: F, =pA p(sin 8, -sin e,)
Power P=FU=pAVU(V-U)
= pA V3r( 1 -r)
Jet on moving curved vane
U
where: r=-
V' sina cost?,
sin 8,
Jet on angfed plate
U
F=pAV(V-U)(l--cost?) in direction of V where: r=- V'
P=p~V~r(l-r)(l -cost?)p