This paper outlines the handling of a semi-closed cycle gas turbine, its working fluid is carbon dioxide and the fuel is low heating value gas from coal; however, at startup air and natural gas are used. The objective of the machine is to produce clean electricity with the smallest efficiency penalty. Many aspects of the operation of the engine are examined in this paper; these include starting requirements, stator vane and bleed valve scheduling, and the working fluid transition from air to carbon dioxide. Other features highlighted are the compressor operating lines and surge margins. The present paper describes the salient features of the three main stages into which the engine operation has been divided. These stages are: startup to synchronous idle, change of working fluid (from air to Carbon Dioxide-Argon) and fuel (from natural gas to coal synthetic gas) at synchronous idle, and part load operation. Preliminary findings show that engine handling can be carried out effectively with variable stators. This is possible because of the two-shaft gas generator. Another point of interest is the large increase of corrected speed relative to rotational speed experienced when the working fluid changes from air to carbon dioxide. In general the control of the engine does not seem to present any insurmountable problems despite the complexities arising from the need to change working fluid and fuel. [S0742-4795(00)02903-3]

1.
Ulizar, I., and Pilidis, P., 1997, “Design of a Semiclosed Cycle Gas Turbine with Carbon Dioxide-Argon as Working Fluid,” ASME Paper 97-GT-125.
2.
Ulizar, I., and Pilidis, P., 1996, “GTSI, Simulation of Gas Turbines with Unorthodox Working Fluids and Fuels,” Turbomacchine 96. Italian Thermotechnical Conference, Genova.
3.
Palmer, J. R., 1983, “The TURBOMATCH scheme for Gas Turbine Performance Calculations,” users’ guide, Cranfield Institute of Technology, United Kingdom.
4.
Keenan, J. H., Kaye, J., and Chao, J., Gas Tables, International Version.
5.
Hunter, I. H., 1994, “Design of Turbomachinery for Closed and Semiclosed Gas Turbine Cycles,” M.Sc. thesis, Cranfield University, United Kingdom.
6.
Navaratnam, M., 1994, “The Investigation of an Aeroderivative Gas Turbine Using Alternative Working Fluids in Closed and Semiclosed Cycles,” M.Sc. thesis, Cranfield University, United Kingdom.
7.
Massardo
,
A.
, and
Satta
,
A.
,
1990
, “
Axial Flow Compressor Design Optimization: Part. I—Pitchline Analysis and Multivariable Objective Function Influence
,”
ASME J. Turbomach.
,
112
, pp.
399
404
.
8.
Massardo
,
A.
,
Satta
,
A.
, and
Marini
,
M.
,
1990
, “
Axial Flow Compressor Design Optimization: Part II—Through Flow Analysis
,”
ASME J. Turbomach.
,
112
, pp.
405
410
.
You do not currently have access to this content.