Determine ratio between mass flow rate to condensing steam, Mechanical Engineering

Assignment Help:

Determine ratio between mass flow rate to condensing steam:

In steam power plant, the steam 0.1 bar and 0.95 dry enters condenser and leaves as saturated liquid at 0.1 bar and 45°C. Cooling water enters condenser in separate steam at 20°C and leaves at 35°C without any loss of its pressure and with no phase change. Neglecting heat interaction between condenser and surroundings and changes in kinetic energy and potential energy, determine ratio between mass flow rate of cooling water to condensing steam.              

Sol.: Given that:

Inlet condition of steam: Pressure 'P1' = 0.1 bar dryness fraction x = 0.95 The exit condition of steam saturated water at 0.1 bar and 45°C Inlet temperature of cooling water = 20°C Exit temperature of cooling water = 35°C Applying SFEE to control volume Q - Ws  = mf [(h2  - h1)+  ½(V22 - V12) + g(z2 - z1)]

1991_Determine ratio between mass flow rate to condensing steam.png

Figure

neglecting changes in kinetic and potential energies. And there is no shaft work that is.; Ws  = 0

Q = mf (h2  - h1)

h1 = hf1  + xhfg1

= 191.81 + 0.95 (2392.82) = 2464.99 kJ/kg

h2 = hf2  at 0. 1 bar (as the water is saturated liquid)

h2 = 191.81 kJ/kg

Q = mf (191.81 - 2464.99)

= - 2273.18mf  kJ/kg                              ...(i)

negative sign shows the heat rejection.

 

1973_Determine ratio between mass flow rate to condensing steam1.png

By energy balance; Heat lost by steam = Heat gained by cooling water

Q = mfw.Cw  (T4  - T3) = mfw  x 4.1868(35 - 20) = 62.802mf                ...(ii)

Equate equation (i) and (ii); We get Q = -2273.18mf  = 62.802mfwmfw/m = 36.19 Ratio of mass flow rate of cooling water to the condensing steam = mfw/mf  = 36.19                                                                      


Related Discussions:- Determine ratio between mass flow rate to condensing steam

Turnning fixtures, what are the forces acting on workpiece during turning p...

what are the forces acting on workpiece during turning process. how workpiece should be clamp

Relation in maximum tensile and maximum compressive stress, Q. 11: What is ...

Q. 11: What is relation between the maximum tensile stress and the maximum compressive stress in any section of beam? Sol.: L et us assume inverted angle section of the beam a

.fluid mechanics., to find a horizontal force acting on a body which is inc...

to find a horizontal force acting on a body which is inclined to the plane with a particular angle

Calculate the power angle, Question: A 3-phase, 15 kV, 4-pole, cylindri...

Question: A 3-phase, 15 kV, 4-pole, cylindrical rotor synchronous generator is connected to infinite bus running at 50 Hz. The synchronous reactance of the machine is X s = 0.

Draw body centred cubic structure, Draw BCC structure and determine its num...

Draw BCC structure and determine its number of atoms per unit cell, co-ordination number and highest edgeradius relation. Draw FCC structure and determine its number of atoms pe

Draw a diagram of a simple carburettor, a) Draw a diagram of a simple carbu...

a) Draw a diagram of a simple carburettor and briefly explain its function. b) What are the basic characteristics of fuels for CI engines.

Evaluate the diameter of bar, As a student engineer illustrate what design ...

As a student engineer illustrate what design consideration you would like to account for parts manufactured by machining and forging. A circular bas of 500mm length is hinghed f

Show space considerations for plant, Q. Show Space Considerations for plant...

Q. Show Space Considerations for plant? There are particular spacing constraints which need particular care and attention when optimizing the layout area utilization in both ne

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd