Rankine cycle: Difference between revisions
Restored page from Google Cache, uploaded by John Pye |
No edit summary |
||
| Line 1: | Line 1: | ||
The [http://en.wikipedia.org/wiki/Rankine_cycle Rankine cycle] is the basic cycle used in most coal-fired power stations, as well as in most concentrating solar thermal (CST) power plants. These cycles can currently be modelled in ASCEND through the use of the external-library [[freesteam]] routines for steam property calculations. | The [http://en.wikipedia.org/wiki/Rankine_cycle Rankine cycle] is the basic cycle used in most coal-fired power stations, as well as in most concentrating solar thermal (CST) power plants. These cycles can currently be modelled in ASCEND through the use of the external-library [[freesteam]] routines for steam property calculations. | ||
A sequence of models of increasing order of complexity are given in the file {{src|models/johnpye/rankine.a4c}}. The models include test cases that reproduce values calculated in the textbook by Moran & Shapiro<ref>Moran & Shapiro, ''Fundamentals of Engineering Thermodynamics'', Wiley, 4th Ed. | |||
A sequence of models of increasing order of complexity are given in the file {{src|models/johnpye/rankine.a4c}}. The models include test cases that reproduce values calculated in the textbook by Moran & | |||
You can load these models and solve them, and then play around with operating parameters and limits. | You can load these models and solve them, and then play around with operating parameters and limits. | ||
| Line 13: | Line 12: | ||
The model file {{src|models/johnpye/rankine.a4c}} contains models of | The model file {{src|models/johnpye/rankine.a4c}} contains models of | ||
* pump with isentropic efficiency | * pump with isentropic efficiency | ||
| Line 27: | Line 25: | ||
Currently these models are all hard-wired to use steam as their working fluid; we'd like to change that. | Currently these models are all hard-wired to use steam as their working fluid; we'd like to change that. | ||
== Cycle models == | == Cycle models == | ||
The models in the {{src|models/johnpye/rankine.a4c}} file are | The models in the {{src|models/johnpye/rankine.a4c}} file are | ||
* <tt>rankine</tt> - the simplest possible Rankine cycle | * <tt>rankine</tt> - the simplest possible Rankine cycle | ||
| Line 41: | Line 36: | ||
Some of these models require certain solver parameters to be set before they are solved; check the instructions in the code file. | Some of these models require certain solver parameters to be set before they are solved; check the instructions in the code file. | ||
== References == | == References == | ||
[[Category:Examples]] | |||
Revision as of 05:26, 29 July 2010
The Rankine cycle is the basic cycle used in most coal-fired power stations, as well as in most concentrating solar thermal (CST) power plants. These cycles can currently be modelled in ASCEND through the use of the external-library freesteam routines for steam property calculations.
A sequence of models of increasing order of complexity are given in the file models/johnpye/rankine.a4c. The models include test cases that reproduce values calculated in the textbook by Moran & Shapiro<ref>Moran & Shapiro, Fundamentals of Engineering Thermodynamics, Wiley, 4th Ed.
You can load these models and solve them, and then play around with operating parameters and limits.
A sample plot generated using the Rankine cycle models as a base, plotted from within ASCEND (numbers added later), is shown below:
Components
The model file models/johnpye/rankine.a4c contains models of
- pump with isentropic efficiency
- turbine with isentropic efficiency
- condenser with outlet steam quality specified
- boiler with outlet temperature specified
- steam trap with inlet steam quality specified
- bleed point
- open feedwater heater
- closed feedwater heater (with temperatures on one side known; not LMTD etc calculation here)
We also have full-blown heat exchanger models that we are in the process of validating currently (by Jose Zapata)
Currently these models are all hard-wired to use steam as their working fluid; we'd like to change that.
Cycle models
The models in the models/johnpye/rankine.a4c file are
- rankine - the simplest possible Rankine cycle
- rankine_reheat - Rankine cycle with an additional boiler stage
- rankine_regen - regenerative Rankine cycle (one bleed, with open feedwater heater)
- rankine_reheat_regen reheat-regenerative Rankine cycle, with two turbines, two bleeds, one open feedwater heater and one closed feedwater heater.
Some of these models require certain solver parameters to be set before they are solved; check the instructions in the code file.