Question

A reducing pipe bend is held in place by a pedestal as shown. There are expansion joints at sections 1 and 2, so no force is transmitted through the pipe past these sections. The pressure at section 1 is 20 psig, and the rate of flow of water (p=1.94 slug/ft3) is 2 cfs. Find the forces in the x and y directions and the moment M that must be applied at the pedestal to hold the bend stationary. A top view is shown. Points 1 and 2 lie in the same horizontal plane. Assume the flow is irrotational, and neglect the influence of gravity. 6 in. diameter 24 in. tit 4 in. diameter

Answer 1

Answer:

A reducing pipe bend in place by a pedestal s shown in the below figure.

>N 6in 24 in >X

Given that pressure at station (1) P, = 20psig Discharge Q = 24 ) V, - 10.19 fils velocity Y- V- 2 xus V = 22.92ftls Applying Beanour's equation at sertion and a + Co. Com + C10,1932. (23.7.)" 20 X14 4 1.94 42.922 2 7.94 022.92) 2 1484.536 + 51.9182 1.94 2 1484.536+ 51.918 - P +262.663 7.94 P 244). 15 psf

momentum equation En X-desection Elx - én[(*), - (01),] Gax +P.A, + BAR ninf-Y-x] q+(20x144), 0.5)+(2441.15) (0.333) --1-94 ((0.5)) 10.19) [22.92+1,19) F +565.487 210.914 -198518 Face :.909.8364 force applied to hold the band roterary es F -909.22 lbf moment of momentum auction in 2-delection Mz -8P, A, +OPA, - Try trening Me rr{P.A. - PEA2 Eriva terry] Mys, (2880x5x60.53?-1244.15), (0.333)2-7 5)*10.19 ) 122.92-10:19] My = 565.484-215.214-49.41 M2 - 300.86 lbf.ft) Moment of momentum escatten Hy-Pecten My +P.A, OZ + P, A, og og mong - Tom

My = -83 [PiA, & Pq Az + en (og to, )] My-rd [Fa] My --21909.2] My -1818.4067 moment applied to hond the band stationery 1M = 6-1818.45 +300.86K).ft. Obf7