Fluid Mechanics

ENME 601

Winter 2013

Dr. Eng. Hamdy Kandil

Assignment# 1

Solution

*Submit your assignment during the tutorial

*There will be an evaluation in the tutorial on this assignment

Problem 1

Estimate the increase in pressure required to decrease the volume of mercury by 0.1%

(Mercury Ev = 2.85 x 1010 Pa)

Problem 2

Contrary to what you may expect, a solid steel ball can float on water due to the surface

tension effect. Determine the maximum diameter of the steel ball that would float on water at

20o C. What would your answer be for an aluminum ball? Take the densities of steel and

aluminum balls to be 7800 kg/m3 and 2700 kg/m3, respectively.

Problem 3 Two vertical, parallel, clean, glass plates are spaced a distance of 2 mm apart. If the plates are placed in water how high will the water rise between the plates due to capillary action?

W= 2 L cos

h L b = 2 L cos

h= 2 L cos / b

Then for =0,

h= 7.49 mm

Problem 4 The clutch system shown is used to transmit torque through a 3-mm-thick oil film with = 0.38N.s/m2 between two identical 30- cm-diameter disks. When the driving shaft rotates at a speed of 1450 rpm, the driven shaft is observed to rotate at 1398 rpm. Assuming a linear velocity profile for the film, determine the transmitted torque.

Problem 5

Freshwater and seawater flowing in parallel horizontal pipelines are connected to each other by a double U-tube manometer, as shown. Determine the pressure difference between the two pipelines. Can the air column be ignored in the analysis? Take the density of seawater to be 1035 kg/m3.

Problem 6 If a 1-ft-diameter, 2-ft-long cylinder floats in an open tank containing a liquid having a specific weight . A U-tube manometer is connected to the tank. When the pressure in pipe A is 0.1 psi below atmospheric pressure, the various fluid levels are as shown. Determine the weight of the cylinder. Note that the top of the cylinder is flush with the fluid surface

Problem 7 Two chambers with the same fluid at their base are separated by a piston whose weight is 25 N, as shown. Calculate the gauge and absolute pressures A and B.

Problem 8 Two water tanks are connected to each other through a mercury manometer with inclined tubes, as shown. If the pressure difference between the two tanks is 20 kPa, calculate a and .