- #1
Blaine
- 4
- 0
Hi posted the question/cry for help in a regular thread but thought it might fit in here as well.
Hello All,
I am currently trying to optimize a steam power plant cycle and I am stuck... What I am unable to figure out is how to use a Mollier chart/diagram in order to determine the amount of steam I must tap off from my turbine to my feed water heater. I know my feed water heaters inlet and outlet temperatures, mass flow rate, TTD and DCA. I have drawn en expansion line in my Mollier chart, taking into consideration my isentropic efficiency. I have been told that from that line I should be able to make an energy balance and directly read off the bleed temperature, pressure and enthalpy of my steam to my feed water heater. Could someone please shed some light on the matter?? Regards Blaine
Forward preheater:
mass flow rate out = 50 kg/s
h out = 994.9 KJ/kg
t out = 231 deg C
h in = 771.9 KJ/Kg
t in = 182 deg C
Heat is added after the feed water heater in order to get the turbine steam entry data, see below.
Turbine steam entry data:
P in = 80 bar
t in = 500 deg C
During the expansion process steam is bled off from the turbine to the feed water heater in order to raise the feedwater temperature from 182 deg C to 231 deg C. The question is how much steam? At what pressure? At what temperature? How can this be read off from the expansion line in my Mollier diagram?
Steam data:
t out bled steam = 191 deg C
t in (bled steam) = unknown
mass flow (rate bled steam) = unknown
Hope this is clear and hope someone can shed some light as I am stuck... Thanks Blaine
Hello All,
I am currently trying to optimize a steam power plant cycle and I am stuck... What I am unable to figure out is how to use a Mollier chart/diagram in order to determine the amount of steam I must tap off from my turbine to my feed water heater. I know my feed water heaters inlet and outlet temperatures, mass flow rate, TTD and DCA. I have drawn en expansion line in my Mollier chart, taking into consideration my isentropic efficiency. I have been told that from that line I should be able to make an energy balance and directly read off the bleed temperature, pressure and enthalpy of my steam to my feed water heater. Could someone please shed some light on the matter?? Regards Blaine
Forward preheater:
mass flow rate out = 50 kg/s
h out = 994.9 KJ/kg
t out = 231 deg C
h in = 771.9 KJ/Kg
t in = 182 deg C
Heat is added after the feed water heater in order to get the turbine steam entry data, see below.
Turbine steam entry data:
P in = 80 bar
t in = 500 deg C
During the expansion process steam is bled off from the turbine to the feed water heater in order to raise the feedwater temperature from 182 deg C to 231 deg C. The question is how much steam? At what pressure? At what temperature? How can this be read off from the expansion line in my Mollier diagram?
Steam data:
t out bled steam = 191 deg C
t in (bled steam) = unknown
mass flow (rate bled steam) = unknown
Hope this is clear and hope someone can shed some light as I am stuck... Thanks Blaine