ME 352 Fluid Dynamics Fall 2015
HW3
1. Assume that the speed of sound, c, in a fluid depends on an elastic modulus, Ev, with dimensions
of FL-2, and the fluid density, , in the form c=(Ev)a()b. If this is to be a dimensionally
homogeneous equation, what a
ME 352 Fluid Dynamics Fall 2015
HW2
1. The force, F, of the wind blowing against a building is given by
=
2
2
,
where V is the wind speed, the density of the air, A the cross-sectional area of the building, and
CD is a constant termed the drag coefficie
1
CE309FluidMechanicsNorthDakotaStateUniversity
HW-W8 Solutions
HW32
10.16
Manning Eq. V=Cu/n*(Rh )^(2/3)*(S0)^(1/2)
b+2my
y
y
b
Rectangle
A = yb
Pw = b+2y
y
m:1
r
b
Trapezoid
A = (b+my)y
Pw = b+2y(1+m^2)^0.5
HW 10-2 Problem 10.16 on page 483
Trapezoidal
1
CE 309 Fluid Mechanics
North Dakota State University
HW-W4 Solutions
HW14
5.4.3 (p.140)
h = 8 ft
(1)
(2)
8 ft , Z1
Given: h
Z2
Z , V1
22 ft / s , V2
0 ft / s ,
62.4lb / ft 3 , p1
SOLN:
Stagnation pressure on the nose of a fish:
p2
p2
p1
62.4
V12
2g
8
h
1
CE 309 Fluid Mechanics
North Dakota State University
HW-W3 Solutions
HW11
4.5.3 (p106)
Given
1000 kg / m 3 ,
w
s 1.4, D 150 mm
Q
Q
1
4
A
VA
0.152 0.8
m
Q
s
G
Q
gm
w
9.81 m / s 2
g
0.15m, V
0.8 m / s
1
D2
4
0.01414 m 3 / s 14.14 L / s
Q 1.4 1000 0.0141 1
1
CE309FluidMechanicsNorthDakotaStateUniversity
HW-W2 Solutions
HW5
3.2.3
Given: ZA = 18ft., pA = 11.4 psi
ZB = 12 ft., pB = 13.7 psi
SOLN:
p = - Z (incompressible fluid)
p B p A = ( Z B Z A )
=
pB p A
=
ZA ZB
(13.7 11.4) psi 144
(18 12) ft
ft 2
in.2 = 55
1
CE309FluidMechanicsNorthDakotaStateUniversity
Homework Solutions
HW-W1 Solutions
HW1
1.5.1
Demonstrate that Eq. (6.5) is dimensionally homogeneous.
Answer:
Eq. (6.5)
Begin with the first term, the sum of all forces. We know that force is characterized b