a) Develop an expression for the pressure loss across a conical contraction of diameter Di and Dz in a given length L for a laminar flow. Explain the physical significant of equation. AN(8) b) A civil engineer wants to measure velocity in a water tunnel. Due to budgetary restrictions, he cannot afford a pitot-static tube, so he inserts a total-head probe and a static-head probe, as shown, both in the mainstream away from the wall boundary layers. The two probes are connected to a manometer. Write an expression for tunnel velocity V in terms of the parameters in the figure. Is it critical that h1 be measured accurately? And how does part (a) differ from a Pitot - static tube formula? total head (1) h1 static head (2) h2 h3 Pw, Pm AN(7) c) By model testing, do you think it is possible to predict the exact behavior of the prototype? Explain with practical examples. AP(5) d) Would you prefer the use of venturimeter to an orifice meter? Explain the reason for your choice.