nan Sanjay

Comparative evaluation of gas turbine power plant performance for different blade cooling means

Abstract The thermodynamic performance of a gas turbine power plant has been compared for different means of blade cooling in this work. Seven schemes involving air and steam as coolants under open- and closed-loop cooling means have been studied. The closed-loop cooling includes only the internal convection cooling (ICC) technique, while the open-loop cooling schemes include the internal convection, film, and transpiration cooling means. Comparative evaluation shows that among all the cooling schemes considered, the open-loop steam ICC offers highest specific work and thus highest values of plant efficiency of about 50 per cent, whereas open-loop film steam cooling, transpiration air cooling, film air cooling, and internal convection air cooling have been found to yield lower values of plant efficiency in decreasing order. The specific work is higher for all open-loop steam cooling means due to steam injection into the hot gas stream of the turbine.

Thermodynamic analysis of the effect of blade cooling methods on air humidifier integrated gas turbine cycle

The paper investigates the effect of compressor pressure ratio, turbine inlet temperature, ambient relative humidity (RH) and ambient temperature on the performance parameters of a gas turbine cycle with evaporative cooling of inlet air and different means of blade cooling. The cooling techniques include film, transpiration and internal convection cooling (ICC). The mass of coolant required for turbine blade cooling is found to decrease with a decrease in ambient temperature and ambient RH. The coolant mass required for turbine blade cooling is lowest for transpiration cooling (TC) followed by film and ICC. However, the highest reduction in coolant mass and the highest enhancement in plant efficiency and work (due to the decrease in ambient RH and ambient temperature) are observed in case of ICC followed by film cooling and TC. The increase in performance parameters due to the addition of inlet cooling system is also found to be maximum for ICC. The inlet cooling improves the plant efficiency by 11·3% and...

Application of CAD and reverse engineering methodology for development of complex assemblies

Purpose – In the present paper, a CAD and reverse engineering (RE) methodology has been adopted for the development of a complex assembly of a TFC 280 crane cabin. A different approach has been adopted to eliminate fouling as well as interference with other components of the crane such as boom, gantry, front drum, rear drum, etc. with its cabin. The paper aims to discuss these issues. Design/methodology/approach – A dummy 3-D CAD model of the assemblies has been made using assembly constraints of Master Assembly and then checked for fouling and interference using IDEAS NX 12 to validate cabin design. In fabrication industries, one of the critical challenges is to maintain close geometric tolerances in finished products, which have been taken care of by the use of accurate value of K-factor. Findings – Ergonomics of the re-engineered crane cabin has also been improved by providing rear vision and improvement in operators forward visibility from 165° to 180°. Originality/value – The work has been carried o...

Exergy analysis of effect of air/fuel ratio and compression ratio on rational efficiency of gas/steam combined cycle

AbstractThe paper presents exergy analysis of a gas/steam combined cycle also called gas turbine combined cycle. The second law approach has been used to evaluate component wise exergy destruction for different values of investigated parameters. The cycle components, i.e. compressor, gas turbine (high pressure and low pressure), combustor, heat recovery steam generator (HRSG), stack, steam turbine and water cooled condenser have been investigated with respect to the effect of varying values of air/fuel ratio and compression ratio on the performance parameters like component-wise percentage exergy destruction and rational efficiency of gas turbine and steam turbine and the results have been presented. Results show that higher values of compression ratio and low air/fuel ratio correspond to lower exergy destruction associated with combustion. The effect of turbine exit temperature on the rational efficiency of plant has been discussed. It has been concluded that for maximising plant efficiency, turbine inle...

Parametric analysis of effect of blade cooling means on gas turbine based cogeneration cycle

AbstractThermodynamic performance analysis of cogeneration cycle based on a state of the art gas turbine has been dealt with in this paper. A configuration has been conceptualised using the latest generation gas turbine MS9001H that uses either steam or air to cool the hot gas path components. Gas turbine performance is evaluated considering different blade cooling means. In this arrangement, the above conceptualised topping cycle, and the bottoming cycle comprising of a two pressure heat recovery steam generator (HRSG) in cogeneration configuration is selected for analysis. In HRSG, one of the steam drums generates steam for gas turbine stage cooling as per requirement and the other drum generates steam for process heating. The cycle performance is predicted based on parametric study carried out after modelling the various elements of cycle, such as compressor, combustor, cooled gas turbine, HRSG, etc. The performance is predicted based on parameters such as fuel utilisation efficiency (FUE), power to he...

Thermoeconomic Modelling and Analysis of Energy Conversion System: Intercooled Recuperated Gas Turbine

Global increase in population growth and improved living standards leads to an increase in energy demand that too at a lowest possible cost. This increased rate of energy demand challenges the energy engineers for effective energy production at minimum possible cost. In this regard, an analysis of power utilities from both perspectives, i.e. fuel efficiency and cost effectiveness becomes necessary to predict the thermodynamic and economic performance of energy systems. In the present work, intercooled recuperated gas turbine cycle-based power utility has been conceptualized and the same has been thermoeconomically analysed by using the ‘Average Cost Theory’ approach. The present article deals with the mathematical modelling of each and every component of cycle and the so obtained results are analysed on the basis of effect of key operating parameters (compressor pressure ratio, turbine inlet temperature and ambient temperature) on thermodynamics and economics of the investigating power utility. The analysis reports that during summer seasons, the decline in plant-specific work can be seen up to 10% for increase in ambient temperature by 20 °C, while for base case parameters (rpc = 30, TIT = 1500 K, ηAC = 88% and ηGT = 90%), the plant-specific work, total cost rate and exergetic efficiency for investigating cycle being are 600 kJ/kg, 23.61

Performance of Integrated Combined and Cogeneration Cycles Using Latest Gas Turbines

/h and 48.29%, respectively.

Thermodynamic Evaluation of Combined Cycle Using Different Methods of Steam Cooling

The paper deals with the thermodynamic performance of combined and cogeneration cycles using the state of the art gas turbines. A configuration has been conceptualized using the latest gas turbine MS9001H that uses steam to cool the hot gas path components. In order to study the effect of cooling means, the same gas turbine is subjected to transpiration air cooling. Using the above mentioned conceptualized topping cycle, the bottoming cycle selected consists of a two-pressure reheat heat recovery steam generator (HRSG) with reheat having two options. First option is the integrated system (IS), which is a combined/cogeneration cycle, and the other is called the normal cogeneration cycle (NC). Both of these cycles are subjected to steam and transpiration air-cooling. The cycle performance is predicted based on parameteric study which has been carried out by modeling the various elements of cycle such as gas, compressor combustor, cooed gas turbine, HRSG steam turbine, condenser, etc. The performance is predicted for parameters such as fuel utilization efficiency (ηf ), power-to-heat-ratio (PHR), coolant flow requirements, plant specific work, etc. as a function of independent parameters such as compressor pressure ratio (rpc ) and turbine inlet temperature (TIT), etc. The results predicted will be helpful for designers to select the optimum compressor pressure ratio and TIT to achieve the target fuel utilization efficiency, and PHR at the target plant specific work.© 2004 ASME

Performance Enhancement of Advanced Combined Cycles

This paper deals with comparative study of the influence of different methods of steam cooling on the performance of simple combined gas/steam cycle plants. The topping cycle chosen is simple gas turbine while the bottoming cycle is a triple-pressure reheat steam cycle. Steam has been chosen as the cooling medium to be studied, as it is the most promising medium. All possible open and closed loop cooling with steam as the cooling medium have been considered. The prediction is based on the modeling of various elements of simple combined gas/steam cycle considering the real situation. The study shows that closed loop steam cooling is superior as compared to other steam cooling methods. However even though other two methods are slightly inferior technologically, but they do not suffer from the chances of problems of cogging of coolant holes if the steam is not ultra pure.Copyright

Thermodynamic Evaluation of Advanced Combined Cycle Using Latest Gas Turbine

This paper reports on the development requirements of gas/steam combined cycle with an aim to achieve plant efficiency greater than 62% through various development possibilities in gas turbine and steam turbine cycle by taking a reference combined cycle configuration (MS9001H gas turbine and three pressure heat recovery steam generator with reheat). The innovative development possibilities include the advanced inlet design to reduce pressure loss, the increase in turbine inlet temperature, use of advanced turbine blade material, increased component efficiency, improved turbine cooling technologies along with better cooling medium, incorporating intercooling, reheat and regeneration either separately or in combination with simple gas turbine cycle using higher compressor pressure ratio, better utilization of heat recovery steam generator, minimum stack temperature, single shaft system configuration, etc. Based on the quantification of each development item, if incorporated in reference cycle, it has been estimated that the combined cycle as the potential to achieve the plant efficiency in excess of 63%.Copyright