The Steam Injector
A theoretical and practical treatise on the design and operation of injectors and on the flow of fluids through and the design of nozzles.

NOZZLE DIMENSIONS. 101 Momentum of + Momentum of _ Momentum of steam jet water jet ~ delivery jet Ws x Vs + W„ x VH, = Wd x Vt, But Wrf = area of delivery uozzle throat (Ad) x density of delivery jet at the throat (p,;) x velocity of the jet at the throat (Vrf) ; therefore Ws x Vs + Ww x V,„ = A„ x Pd x V/. Novv the velocity of the delivery jet (V(J at the delivery nozzle throat is, if we neglect all considerations of losses, an amount equivalent to that due to the difference between the pressure in the vessel being fed (!’,,) and the pressure at the said throat (Po) or since V2 = 2 g H, and H = —, P then V/ = ~ PQ. m 1 Prf. 1 he above momentum equation now becomes : Ws x Vs + Ww x Vw = A(, x Pd x P£> P<i = A(i x 2</(Pd- Po). (rom formula (xiv.), which ia as follows,' we kuow that Titking- n = TI 35, then Ws = 3-6 As /—s. If we neglect W,„ x Vrø, the equation then becomes : or 3-6 A, x Vs = Ati x 2y (P - Po) ; A> = 2 7 (Pa ~ Åd 3-6 /^-s x Vs 7 vs