10cv35 USN Third Semester B.E. Degree Examinationo June/July 2014 Fluid Mechanics ",,*.Fr:,= ! ifhq 3 hrs. ,,. ._,"rt Note: Answer any FIVEfull questions, selecting atleast TWO questions from each part. I m* 4) o a. E1 o C) E9 -y. b. 6 ^^l =oo o-o i) ii) iii) iv) v) \ MbSi.density. SpecifiCgravity. Dynamicviscosity. Vapour pressure. Capillarity. (10 Marks) A 150mm diameter Vefiical cylinder rotates conCentrically inside another cylinder of diameter 151.0mm. Both cylinders are 250mm high. The space between the cylinders is filled with a liquid whose viscosity is unknown. If a torque of 12 N-m is required to rotate the inner cylinder at 100rpm. Detbrmine the viscosity of the fluid. (10 Marks) ! -.E ::L v5 (.) PART _ A Defini'ihA.following fluid properties with units: ''''lt ! Max. Marks:100 , = 4x b. c. With neat sketch, explain Bourdon's piessgre gauge. (06 Marks) An open tank contains water upto a depth of lm and above it an oil of specific gravity 0.9 for a depth of 1m. Find the preisure intensiry i) At the interface of the lwo liquids and ii) At the bottom of tfu"tank. (08 Marks) a. b Define: i) Total ptqSpui.; ii) Centre of pressure (04 Marks) pbtain an expression for total pressure and centers of pressure for inclined surface submerged in,liquid (08 Marks) A trapezoidai'channel 2m wide at the bottom and 1m deep has side ilopes 1 :1. Determine: O() bot ,6 J 'ia oi= c. = :'i6. o" o'" o-i i.tt State and prove Pascal's -9 E:] law. a. ,.. (06 Marks) i)rotat.pre'sSure;ii)Centreofpressure,whenitisfullofwater. arE := IH A F >,= ,, (04 Marks) ,..,,*,"' 6',,. Obtain an expression for continuity equation for tluee dimensional flows. (08 Marks) . Ifforatwodimensional potential flow,thevelocitypotential isgivenbV0:x(2y-1). Determine the velocity at the point P(4. 5). Determine also the value of stream lunction rq at the point (08 Ntart<s) ry$ ,*... e; ; ;) 5 a i P. ->r \J< * c.] ;5a. tD. ui !9. o o. . PART _B made. Derive Bernoulli's equation from Euler's equation with assurnptions (0s Marks) Derive the equation for the discharge through venturimeter. (06 Marks) Water is flowing through a pipe having diameter 300mm and 200mm at the bottom and upper end respectively. The intensity o^f pressure at the bottom end is 24.52 N/cm2 and the pressure at the upper end is 9.81 N/cm2. Determine the difference in datum head if the flow through pipe is 40/ps. (06 Marks) I of2 10CV3s 2 ofl