G. Kosman

The influence of the start-ups and cyclic loads of steam turbines conducted according to European standards on the component's life

Co-operation with West European systems involves the necessity of satisfying a number of criteria put forward by UCPTE. Among them there are more rigorous recommendations concerning the rate of decreasing and increasing the power output, the reduction of the technical minimum of the power unit, shorter starting times and the sustained operation for the plants own demand or idle running.

Analysis of cycle configurations for the modernization of combined heat and power plant by fitting a gas turbine system

The application of a gas turbine generally allows to increase the number of possible configurations of cogenerated heat and electrical power systems, which became a significant substitute for classic, coal-fired power plants. They are characterized by better thermodynamical, economical, ecological, and operating indexes. Gas turbine units are also the best option for the modernization of existing power plants. This paper discusses the effectiveness of various technological configurations with gas turbines, which are to be applied during modernization projects of already existing conventional combined heat and power plants. In the analysis enthalpy and entropy methods were applied. Algorithms of the entropy method allow to determine the entropy generation in each section of a combined heat and power (CHP) plant. Several criteria were taken into consideration while analyzing the effectiveness of technological cycle configurations with gas turbines. These include the energy effectiveness, the efficiency of the HRSG and the steam cycle, the efficiency of the whole thermal electric power station, the exergetic efficiency of the HRSG and the steam cycle, and the fuel efficiency index. It was assumed that gas turbines operate under their nominal conditions. The composite curves were also taken into consideration while choosing the type of the turbine. The modernization project tends not to eliminate those existing power plant sections (machines and equipment), which are able to operate further. The project suggests that those units should remain in the system, which satisfy the applied durability criterion. The last phase of the optimization project focuses on the sensibility verification of several steam-gas CHP plant parameters and their influence on the whole system.

On-Line Performance Evaluation of CHP Plant With Cooled Gas Turbine Supported by Off-Line Analysis Results

This paper presents a methodology of diagnostic investigations for gas turbines. The key feature is that the analysis is carried out in two modes: off-line and on-line. The first mode is performed periodically. It involves detailed measurements. Values obtained from measurements create the input data for further analysis. Health state of a gas turbine is then evaluated. The evaluation bases on calculation of several health state parameters. The on-line diagnostic mode uses these parameters as a reference state. The usual lack of measurements available in the on-line investigations creates the need for additional input data for the analysis. Therefore diagnostic investigations are supported by the results from the off-line mode. One of the main problems to be solved in diagnostic analysis is the appropriate modeling of gas turbine operation. An approach presented here regards the operation in various conditions, meaning also off-design operation.Copyright

Analysis of Cycle Configurations for the Modernization of Combined Heat and Power Plant by Fitting a Gas Turbine System

The application of a gas turbine generally allows to increase the number of possible configurations of cogenerated heat and electrical power systems, which became a significant substitute for classic, coal-fired power plants. They are characterized by better thermodynamical, economical, ecological and operating indexes. Gas turbine units are also the best option for the moderinization of existing power plants. This paper discusses the effectiveness of various technological configurations with gas turbines, which are to be applied during modernization projects of already existing conventional combined heat and power plants. In the analysis and entropy methods were applied. Algorithms of the entropy method allow to determine the entropy generation in each section of a combined heat and power (CHP) plant. Several criteria were taken into consideration while analyzing the effectiveness of technological cycle configurations with gas turbines. These include the energy effectiveness, the efficiency of the HRSG and the steam cycle, the efficiency of the whole thermal electric power station, the exergetic efficiency of the HRSG and the steam cycle, and the fuel efficiency index. It was assumed that gas turbines operate under their nominal conditions. The composite curves were also taken into consideration while choosing the type of the turbine. The modernization project tends not to eliminate those exiqsting power plant sections (machines and equipment), which are able to operate further. The project suggests that those units should remain in the system, which satisfy the applied durability criterion. The last phase of the optimization project focuses on the sensibility verification of several steam-gas CHP plant parameters and their influence on the whole system.Copyright

Life Assessment of Turbine Components Under Random Loading

Life assessment of gas turbine components under random loading is presented in the paper. Two examples were considered. One examines changes in the probability of failure of an expansion turbine rotor after an increase of the gas temperature. The other assesses the probability of failure of a shell due to fatigue.© 2000 ASME

On-Line and Off-Line Steam Turbine Component Strain States Monitoring for the Diagnostic System

This paper presents the main assumptions and targets of the strain and stress states modelling of the steam turbine components. The analysis is undertaken due to the main components of HP and IP turbine sections (inner and outer casings, valve bodies and rotors) working under a significant load. Stress modelling has been divided into two parts: a simplified analysis and the detailed one. The former has been proposed in this way that the on-line calculations can be done. It’s based on special functions built upon multi-variant heat process simulations. The functions mentioned make it possible to describe the maximum component stress from some measured temperatures. This part should meet the requirements due to the stress state modelling during a usual turbine operation.The detailed analysis comprises the unsteady operating conditions, bearing the stamp of intensive heating or cooling processes. As a result of the advanced calculation methods and full stress models being used the analyses is carried off-line.Copyright