1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
cupoosta [38]
2 years ago
5

A steam power plant operates on the reheat Rankine cycle. Steam enters the highpressure turbine at 12.5 MPa and 550°C at a rate

of 7.7 kg/s and leaves at 2 MPa. Steam is then reheated at constant pressure to 450 °C before it expands in the low-pressure turbine. The isentropic efficiencies of the turbine and the pump are 85 percent and 90 percent, respectively. Steam leaves the condenser as a saturated liquid. If the moisture content of the steam at the exit of the turbine is not to exceed 5 percent, determine (a) the condenser pressure, (b) the net power output, and (c) the thermal efficiency

Engineering
1 answer:
gayaneshka [121]2 years ago
8 0

Answer:

A) condenser pressure = 9.73 kPa,

B) 10242 kw

C) 36.9%

Explanation:

given data

entrance pressure of steam = 12.5 MPa

temperature of steam = 550⁰c

flow rate of steam = 7.7 kg/s

outer pressure = 2 MPa

reheated steam temperature = 450⁰c

isentropic efficiency of turbine( nt ) = 85% = 0.85

isentropic efficiency of pump = 90% = 0.90

From steam tables

at 12.5 MPa and 550⁰c ; h3 = 3476.5 kJ/kg,  S3 = 6.6317 kJ/kgK

also for an Isentropic expansion

S4s = S3 .

therefore when S4s = 6.6317 kJ/kg and P4 = 2 MPa

h4s = 2948.1 kJ/kg

nt = 0.85

nt (0.85) = \frac{h3-h4}{h3-h4s} = \frac{3476.5 - h4}{3476.5 - 2948.1}

making h4 subject of the equation

h4 = 3476.5 - 0.85 (3476.5 - 2948.1)

h4 = 3027.3 kj/kg

at P5 = 2 MPa and T5 = 450⁰c

h5 = 3358.2 kj/kg,  s5 = 7.2815 kj/kgk

at P6 , x6 = 0.95  and s5 = s6

using nt = 0.85 we can calculate for h6 and h6s

from the chart attached below we can see that

p6 = 9.73 kPa, h6 = 2463.3 kj/kg

B) the net power output

solution is attached below

c) thermal efficiency

thermal efficiency = 1 - \frac{qout}{qin} = 1 - ( 2273.7/ 3603.8) = 36.9% ≈ 37%

You might be interested in
Request for proposal (RFP) is a type of document that contains the information and proposals mostly through the bidding process.
Art [367]

Answer:

Answer to the following is as follows;

Explanation:

A request for proposal is a documentation that invites prospective contractors to submit business opportunities to an agency or corporation interested in procuring a commodities, product, or valuable resource through a bid procedure.

A request for proposal (RFP) is a commercial document that introduces a project, defines it, and invites eligible contractors to compete on its completion.

8 0
2 years ago
In which of the following states would homes most likely have the deepest foundation?
Evgen [1.6K]

Answer:

D) Louisiana, to prevent homes from blowing away in hurricanes.

Explanation:

Louisiana is famous for hurricanes i think that if they were well prepared and had deeper foundation the damage may lower by a good lot.

5 0
2 years ago
Calculate the differential pressure in kPa across the hatch of a submarine 320m below the surface of the sea. Assume the atmosph
kicyunya [14]

Answer:

The pressure difference across hatch of the submarine is 3217.68 kpa.

Explanation:

Gauge pressure is the pressure above the atmospheric pressure. If we consider gauge pressure for finding pressure differential then no need to consider atmospheric pressure as they will cancel out. According to hydrostatic law, pressure varies in the z direction only.  

Given:

Height of the hatch is 320 m

Surface gravity of the sea water is 1.025.

Density of water 1000 kg/m³.

Calculation:

Step1

Density of sea water is calculated as follows:

S.G=\frac{\rho_{sw}}{\rho_{w}}

Here, density of sea water is\rho_{sw}, surface gravity is S.G and density of water is \rho_{w}.

Substitute all the values in the above equation as follows:

S.G=\frac{\rho_{sw}}{\rho_{w}}

1.025=\frac{\rho_{sw}}{1000}

\rho_{sw}=1025 kg/m³.

Step2

Difference in pressure is calculated as follows:

\bigtriangleup p=rho_{sw}gh

\bigtriangleup p=1025\times9.81\times320

\bigtriangleup p=3217680 pa.

Or

\bigtriangleup p=(3217680pa)(\frac{1kpa}{100pa})

\bigtriangleup p=3217.68 kpa.

Thus, the pressure difference across hatch of the submarine is 3217.68 kpa.

6 0
3 years ago
What does it mean to say that PEER is a data-driven, consumer-centric, and comprehensive system?
Reika [66]

Answer:

have you heard of gnoogle?

Explanation:have you heard of goongle?

3 0
3 years ago
Read 2 more answers
How does Hydro Technology and Hydro Energy Help with Global Water Issues?
GrogVix [38]
It would have environmental and societal impacts
5 0
2 years ago
Other questions:
  • A device is needed to accelerate a 3000 lb vehicle into a barrier with constant velocity to test its 5 mph bumpers. The vehicle
    12·2 answers
  • The pistons of a V-6 automobile engine develop 226.5 hp. If the engine driveshaft rotational speed is 4700 RPM and the torque is
    14·1 answer
  • An inverting amplifier with +11 V supply voltages normally has a sinusoidal output of 10 Vpp. When checking the circuit with an
    11·1 answer
  • A non-entrepreneurship, work-based, agricultural type of SAE, in which a student learns and gains skills in a paid or unpaid pos
    15·1 answer
  • An op-amp differential amplifier is built using four identical resistors, each having a tolerance of ±5%. Calculate the worst p
    14·1 answer
  • Which step in the engineering design process likely broke down in the following scenario?
    14·1 answer
  • 4.
    6·1 answer
  • In python, how would I randomize numbers and insert them into a file?
    7·1 answer
  • In order to live and grow, bacteria need moisture, food, the right temperature, and ______? Fill in the blank
    5·1 answer
  • A jet of water 75m in diameter,issues with a velocity of 30m/s and impinge on a stationary plate which distort its forward motio
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!