why steam condenser is used ?

1. Steam condenser
By :- lowell harbert

2. Steam condensor
Key points :-
*Latent heat does not change the temperature.
*Sensible heat changes the temprature of the
System.
sensible heat
Water saturated liq.
specific pressure

3. • latent heat
Satu. Liq . Satu. vapour
specific pressure
heat
Satu. Vapour super heated
steam

4. Steam condenser

5. Condenser

6. Power plant

7. • At every pressure there corresponds a
temperature at which any fluid starts boiling is
known as fluid`s boiling point.
• From steam table:-
* pressure * satu. Temp
1 bar 100 c
0.5 bar 81.3 c
0.1 bar 45.8 c
0.05 bar 32.9 c
0.01 bar 7 c

8. Q . Why condenser is needed in steam turbine
power plant?
Boiler turbine
feed pump condenser
Steam turbine power plant

9. What happen when there is no condenser?
Ans. If there is no condensor then steam will
exhaust at atmospheric pressure .
It means we can achieve 100c temperature at
exhaust or during heat rejection.
* Any thermodynamic cycle can have maximum
Efficiency only when there is high temperature
during heat addition and very low temprature
during heat rejection.

10. *For achieving very low temperature at exhaust
*We introduced condensor.
*There is a vacuum which is maintained in the steam
Condensor by vacuum pump .
*Steam expands to very low sub atmospheric
pressure i.e. (0.1 - 0.04 bar).
*After expansion we get very low temprature
correspond to condensor pressure or back
pressure or exhaust pressure.

11. *It should be noted that after expansion
dryness fraction should not be less than 85%.
*Ultimately we can say that condensor provide
very low atmospheric pressure at exhaust of
turbine.

12. *Now question arises up to what level we can
drop the pressure of condensor or what are
the restrictions ?
*Again answer lies in thermodynamical aspect
*It is totally depends upon the temprature o
cooling water which is introducing in
Condenser to condense the steam.
*Suppose the pressure in condensor is
maintained at (0.01bar) it means we can only
achieve 7c after expansion , but we
introducing cooling water of 27c from
atmosphere to

13. Condense the steam ,then it will be a reverse
heat transfer from cooling water to exhaust
steam.
7c steam
Cooling water at 27c Hot water out
InOut

14. Que. What happen when super heated fluid is
passed through a condenser?
Ans. Firstly its temprature is droped down ,then
it`s phase changes.
*Application of condenser in air refrigeration
system:-
Consider air is at 1 bar pressure having boiling
point 4c, But it is present in atmosphere of
32c it means it is in super heated condition.

15. Now if air is compressed isentropically up to
10 bar then it`s temperature will reached to
110c , then if it is passed through condensor
then it`s pressure will not drop down but it`s
temprature will drop down to 35c , and then
it is expand in turbine (expander) then we
can achieve temprature around (-5 to -6 c ) .
This is the principle of air refrigeration system.
And it is used in aeroplanes. it is very low cost
process.