Search Results

In the present paper the environmental impact of a gas-steam combined cycle, in terms of CO2 emissions has been supplemented with the energetic analysis of the cycle. The gas turbine based triple-pressure reheat combined cycle incorporates, vapor compression inlet air cooling and air-film turbine blade cooling, to study the improvement in plant performance and sustainability. A parametric study of the effect of compressor pressure ratio (rp,c), compressor inlet temperature (CIT), turbine inlet temperature (TIT), inlet temperature ratio (rIT), ambient relative humidity and ambient temperature on performance and sustainability has been carried out. The integration of inlet air cooling and gas turbine blade cooling results in a significant reduction in CO2 emission per unit plant output. The integration of vapor compression inlet air cooling to gas turbine based combined cycle, has been observed to improve the specific work by more than 10 %.

The paper presents the effect of ambient and operating parameters on the performance of Marine Gas turbine integrated with vapor refrigeration inlet air cooling. The rational efficiency of gas turbine and along with summation of exergy destruction in all components with and without inlet air cooling has been analyzed. The variation of total exergy destruction of all components indicates that the destruction of exergy is only marginally effected by inlet air cooling. The sensitivity analysis depicting the effect of variation of compressor pressure ratio (rp,c) turbine inlet temperature (TIT), ambient temperature and ambient relative humidity on Gas turbine rational efficiency and non-dimensional component-wise exergy destruction of inlet air cooled gas turbine has been discussed in detail.

A systematic and comprehensive first law analysis of a cooled gas turbine cycle subjected to vapor compressor inlet air cooling (VC-IAC) has been conducted in our study. Film air cooling technique has been implemented to cool the gas turbine (GT) buckets. The gas turbine is subjected to variation of various operating and ambient parameters and the corresponding effect is analyzed to find out the optimal one. The integration of VC-IAC has been reported to further enhance the plant specific work and plant efficiency of gas turbine cycle, the enhancement being higher in regions having a hot and dry climate. This increase in cycle performance due to VC-IAC has been found superior in case of bucket cooled GT cycle when compared to uncooled one. It has further been witnessed that the plant specific work increases by more than 0.35 % and the plant efficiency increases by little above 0.1 % for every 1o C drop in CIT.

Majority of prime movers for ship propulsion used currently are diesel engines mainly because of their elevated efficiency and their ability to run on residual oil. But in view of the increasing awareness for pollution control and stricter environmental regulations, gas turbine cycle can be regarded as a suitable alternative to propel large ships for cargo and military purpose. However during summer and in hot and humid climates, an increase in ambient temperature and ambient relative humidity is observed to adversely affect the performance of gas turbine (GT). In such circumstances, integration of inlet air cooling to GT cycle can be considered as a suitable alternative. The present paper discusses the possibility of using a vapor absorption inlet air cooled gas turbine cycle as a prime mover for marine application.

The innovations in aircraft propulsion have been identified as the key parameter towards the progress in transportation. Continuous advancement in the performance and efficiency of propulsion has enabled aircraft to travel over larger distances with higher speed. Aviation is also responsible for approximately 2% of total greenhouse gas emission and is expected to grow around 3% by 2050. The present article aims to use the exergetic analysis of a turboprop engine which should be helpful in designing of such engines and also helps these engine users to regulate and select the operation modes. A gas turbine with film air cooling of turbine blades has been proposed to be the turboprop engine. The engine is analyzed on exergy point of view at different power loading operation modes and the performance is studied.

In the present scenario, when the non-conventional energy resources are still under development stage for their full potential as a source of energy for our fast growing population, gas turbines are one of the most promising power generation technologies. The gas turbine based power utilities are also gaining acceptance across globe, because of increase in extraction of natural gas. Further reduction in the price of natural gas would also result in the number of gas turbine units installed across globe and thus it is important to carry out the environmental analysis of gas turbine based utilities. The gas turbines are employed in power generation in industries, aircrafts and marine propulsion units. The present exercise carries out thermodynamic performance analysis i.e. energy, exergy and emission performance analysis of an air-craft gas turbine. The gas turbine blades of present cycle are assumed to be cooled by air-film blade cooling technique.

The integration of inlet air cooling to gas turbine based power utilities is a well accepted practice as this modification to the utility delivers superior utility performance. However, application of inlet-air cooling to drive turbines and specifically to marine mobility sector is rare in literature. Marine vessels are generally propelled by diesel engines, however large marine vessels specifically cruise ships and high speed naval vessels may have requirements of higher speeds and on-board power requirements which can fulfilled by gas turbine driving the propellers while on-board power needs can be met by steam turbine power generated from gas turbine exhaust heat. Such gas-steam combined cycles have the potential to become popular for high capacity marine vessels. The choice of gas turbine based combined cycle power plant for marine vessels in comparison to diesel engine powered vessel is also superior due to lower emission from the former.

This paper deals with effect of evaporative inlet air cooling on exergy and emission in basic gas turbine cycle. Inlet air cooled gas turbine based power plants are operational in various parts of the world. The article is an attempt to analyze thermodynamic and emission performance to these cycles. Rational efficiency of gas turbine for cooled inlet air at lower relative humidity is higher; also the exergy destruction in combustor is higher among all other components. For a fixed value of equivalence ratio, residence time, turbine-rotor-inlet temperature and two varying relative humidity effect of various values of compressor ratio on primary-zone-temperature, NOx, CO and UHC emission has been analyzed. It has been observed that the primary-zone-temperature and mass of NOX emission increases with increase in compressor pressure ratio whereas mass of CO and UHC emission decreases with increase in compressor pressure ratio.

In modern turboprop engines, reduction in emission and fuel consumption is the primary goals during the development of gas turbine aero engines. In this paper, a concept has been proposed for hybridizing the air blade cooled turboprop engines by integrating it with a fuel cell. The proposed study focuses on thermodynamic analysis of a turboprop engine integrated to a solid oxide fuel cell (SOFC) system. A solid oxide fuel cell is the perfect candidate for utilizing waste heat available at turboprop engine exhaust, through recuperation process. Integration of SOFC is ultimately leads to enhancement the overall performance of the turboprop-SOFC hybrid system. Power generated by the SOFC system can be utilized by the aircraft and in can complement the auxillary-power-unit (APU) and may even supplement it. On the basis of 1st and 2nd law of thermodynamic modeling analysis of a turboprop-SOFC system has been presented in this article.