100% satisfaction guarantee Immediately available after payment Both online and in PDF No strings attached
logo-home
Solution Manual for Principles of Turbomachinery by Seppo A . Korpela Department of Mechanical and Aerospace Engineering $10.19   Add to cart

Exam (elaborations)

Solution Manual for Principles of Turbomachinery by Seppo A . Korpela Department of Mechanical and Aerospace Engineering

 40 views  0 purchase
  • Course
  • Institution
  • Book

Solution Manual for Principles of Turbomachinery by Seppo A . Korpela Department of Mechanical and Aerospace Engineering

Preview 4 out of 177  pages

  • May 31, 2024
  • 177
  • 2023/2024
  • Exam (elaborations)
  • Questions & answers
avatar-seller
PRINCIPLES OF TURBOMACHINERY


SOLUTIONS MANUAL


by




Seppo A. Korpela
Department of Mechanical and Aerospace Engineering
January 2012




Copyright ⃝2011-2012,
c Seppo A. Korpela

, Chapter 2
Exercise 2.1 Steam flows through a bank of nozzles shown in the figure below,
with wall thickness t2 = 2 mm, spacing s = 4 cm, blade height b = 2.5 cm, and
exit angle α2 = 68◦ . The exit velocity V2 = 400 m/s, pressure is p2 = 1.5 bar,
and temperature is T2 = 200 C. Find the mass flow rate.
Given:

b = 2.5 C s = 4 cm t2 = 0.2 cm α2 = 68◦ V2 = 400 m/s

T2 = 200 C = 473.15 K p1 = 1.50 bar = 150 kPa v2 = 1.4443 m3 /kg
Find: Mass flow rate.
Solution:

A2 = b(2 cos α2 − t2 ) = 2.5(4 cos(68◦ ) − 0.2) = 3.25 cm

A2 V2 3.25 · 400
ṁ = = 4 = 0.09 kg/s ⇐
v2 10 · 1.4443
Note that the specific volume could also be approximated as

R̄T2 8.314 · 473.15
v2 = = = 1.457 m3 /kg
Mp2 18 · 150



V1
t1
s
1




t2



α2 2
V2




2

,Exercise 2.2 Air enters a compressor from atmosphere at pressure 102 kPa and
temperature 42 C. Assuming that its density remains constant determine the spe-
cific compression work required to raise its pressure to 140 kPa in a reversible
adiabatic process, if the exit velocity is 50 m/s.
Given: Since the air is stagnant in the atmosphere, its conditions are the stagnation
conditions. The flow is isentropic and
T2 = 42 C = 315.15 K p1 = 102 kPa p2 = 140 kPa V2 = 50 m/s
Find: Specific work done.
Solution: For isentropic flow T ds = dh − vdp leads to dh = dp/ρ. In addition
h0 = h + V 2 /2 is constant. The flow is assumed incompressible because the
pressure changes only slightly and the exit velocity is small.
p 2 − p1 1 2
w= + V2
ρ 2
The density is
p1 102
ρ= = = 1.128 kg/m2
RT1 0.287 · 315.156
so that
140 − 102 502
w= + = 43.95 kJ/kg ⇐
1.128 2 · 1000
Exercise 2.3 Steam flows through a turbine at the rate of ṁ = 9000 kg/h. The
rate at which power is delivered by the turbine is Ẇ = 440 hp. The inlet total
pressure is p01 = 70 bar and total temperature is T01 = 420 C. For a reversible
and adiabatic process find the total pressure and temperature. leaving the turbine.
Given: The flow is isentropic and
T01 = 420 C p01 = 70 bar ṁ = 9000 kg/h Ẇ = 440 hp
Find: T02 and p02 .
Solution:
Ẇ 440 · 0.7457 · 3600
w= = = 131.2 kJ/kg
ṁ 9000
From steam tables h)1 = 3209.8 kJ/kg, s1 = 6.5270 kJ/kg K. At the exit
h02 = h01 − w = 3209.8 − 131.2 = 3078.6 kJ/kg s2 = 6.5270 kJ/kg K
From the superheated steam tables, or using EES,
p02 = 43.58 bar T02 = 348.5 C ⇐


3

, Exercise 2.4 Water enters a pump as saturated liquid at total pressure of p01 =
0.08 bar and leaves it at p02 = 30 bar. If the mass flow rate is ṁ = 10, 000 kg/h
and the process can be assumed to take place reversibly and adiabatically, deter-
mine the power required.
Given: The flow is isentropic and

p01 = 0.08 bar p02 = 30 bar ṁ = 10.000 kg/h

Find: Ẇ .
Solution: For isentropic flow

p02 − p01 30 − 0.08) · 105
w= = = 2.998 kJ/kg
ρ 998
Therefore
10, 000 · 2.998
Ẇ = ṁw = = 8.33 kW ⇐
3600
Exercise 2.5 Liquid water at 700 kPa and temperature 20 C flows at velocity
15 m/s. Find the stagnation temperature and stagnation pressure.
Given: The flow is isentropic and

p = 700 kPa T = 20 K V = 15 m/s

Find: T0 and p0 .
Solution: Since water is incompressible

V2 152
T0 = T + = 20 + = 20.027 = 20.027 C ⇐
2cp 2 · 4187

1 998 · 152
p0 = p + ρV 2 = 700 + = 700 + 122.75 = 812.3 kPa ⇐
2 2 · 1000
Exercise 2.6 Water at temperature T1 = 20 C flows through a turbine with inlet
velocity V1 = 3 m/s, static pressure p1 = 780 kPa and elevation z1 = 2 m. At
the exit the conditions are V2 = 6 m/s, p2 = 100 kPa and z2 = 1.2 m. Find the
specific work delivered by the turbine.
Given: Assuming that the process is isentropic and given that T1 = 20 C, and

p1 = 780 kPa z1 = 2 m V1 = 3 m/s

4

The benefits of buying summaries with Stuvia:

Guaranteed quality through customer reviews

Guaranteed quality through customer reviews

Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.

Quick and easy check-out

Quick and easy check-out

You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.

Focus on what matters

Focus on what matters

Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!

Frequently asked questions

What do I get when I buy this document?

You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.

Satisfaction guarantee: how does it work?

Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.

Who am I buying these notes from?

Stuvia is a marketplace, so you are not buying this document from us, but from seller a_plus_work. Stuvia facilitates payment to the seller.

Will I be stuck with a subscription?

No, you only buy these notes for $10.19. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

77254 documents were sold in the last 30 days

Founded in 2010, the go-to place to buy study notes for 14 years now

Start selling
$10.19
  • (0)
  Add to cart