ME321 Intro. To Fluid Mechanics Final Exam (12/12/06, 10:45 am ~ 1:15 pm, Open books close notes) 1. A 90oelbow is used to direct water flow at a rate of 20 kg/s in a horizontal pipe upward. The diameter of the entire elbow is 10 cm. The elbow discharges water into the atmosphere, and thus the pressure at the exit is the local atmospheric pressure. The elevation difference between the centers of the exit and the inlet of the elbow is 20 cm. The weight of the elbow and the water in it is considered to be negligible. Determine (a) the gage pressure at the center of the inlet of the elbow, and (b) the anchoring force (in horizontal and vertical directions) needed to hold the elbow in place. Take the momentum-flux correction factor to be 1.05. (15 pts) 2. A reducing elbow is used to deflect water flow at a rate of 50 kg/s in a horizontal pipe upward by an angle θ= 60ofrom the flow direction while accelerating it. The elbow discharges water into the atmosphere. The cross-sectional area of the elbow is 100 cm2at the inlet and 20 cm2at the exit.