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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.

Abstract The current global energy scenario demands for fuel efficient and cost effective thermal systems of energy conversion. It leads to investigation of techniques which can minimize the energy wastage and maximize the utilization of energy. In this regard the present paper proposes a configuration (LM2500+G4 marine engine manufactured by M/S GE Aviation for cogeneration application) for marine propulsion and cogeneration. The exhaust gas temperature of LM2500+G4 marine engine is around 800 K hence heat of this exhaust stream can be utilized to produce process steam for further use. In this particular work the aforesaid configuration has been exergoeconomically analyzed to predict the total cost rate (investment cost rate + fuel cost rate) of the system. The “Average Cost Theory” has been approached for the exergoeconomic analysis. The exergoeconomic analysis is the combined study of thermodynamic concepts and economic principles.

An “APU” (Auxiliary Power Unit) is a small gas turbine engine to provide supplementary power to an aircraft and is located at the tails of larger jets. APU generators provide auxiliary electrical power for running aircraft systems on the ground. Applications include powering environmental systems for pre-cooling or preheating the cabin, and providing power for crew functions such as preflight, cabin cleanup, and galley (kitchen) operation and long-haul airliners must be started using pneumatic power of APU compressor. The Honeywell 131-9A gas turbine APU has 440 kW shaft power and 90 kW electric generator consuming 120 kg fuel/hour. Hybrid power systems based on fuel cells are promising technology for the forthcoming power generation market. A solid oxide fuel cell (SOFC) is the perfect candidate for utilizing waste heat recovery. This case deals with waste heat recovery from fuel cell exhaust using Brayton cycle as bottoming cycle for additional power production.

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.

The aim of this study is to investigate the overall performance (exergetic, exergoeconomic and exergoenvironmental) of CT7-7A turboprop engine manufactured by General Electric Aviation (GE Aviation) and currently used to power CN-235, a medium range transport aircraft. The investigation has been carried out using the thermoeconomic, sustainability and environmental damage cost analysis methods. The adopted turboprop engine has been investigated to observe the behaviour of various performance parameters, sustainability, emission parameters as well as cost parameters of engine. Due to ever increasing demand in air transport systems, focus has been on developing efficient and sustainable systems with lowest possible cost. In order to reduce cost & environmental effects of engine and at same time to acquire higher performance, it is necessary to understand the mechanism that can offer improvements in the engine operating and design parameters so that higher performance can be obtained.

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.

Aircraft engines powering propulsion of the aircraft is the key component of the system. In aircraft industry it is desirable that an aircraft engines should supply high speeds (for military fighters) with low maintenance (for civil airplanes). In this regard an integration of gas turbine engines with traditional propeller has been introduced and termed as turboprop engine. In present work, a gas turbine with cooled blading has been proposed to be the turboprop engine which has been exergoeconomically analyzed to assess the performance and economics related to the proposed turboprop engine. Exergo-economic analysis is a tool which combines thermodynamic analysis and economic principles to provide information that is helpful to predict thermodynamic performance and total cost of the engine (thermal system). The methodology includes energy, exergy and cost balance equations for component-wise modelling of whole system.

Gas turbine technology has traditionally been used by the aviation industry for powering the aircraft including acting as APU. Operational unmanned aerial vehicle (UAV) has a gas turbine which is used as Auxiliary Power Unit (APU) which generically have overall efficiency not exceeding 35% which limits the range in terms of time in the air for the same APU fuel carried onboard. Gas turbine exhaust heat energy is largely wasted and there is scope of its utilization by thermally coupling it with a solid-oxide fuel cell (SOFC). By coupling SOFC with the gas turbine (GT) based power system, a hybrid SOFC-GT based APU system has been proposed for thermodynamic analysis, and the thermal efficiency of the proposed system can be enhanced by 77%. This paper focuses on a thermodynamic cycle analysis of an internal reformed solid oxide fuel cell which is integrated with the gas turbine to form a hybrid APU system for an UAV.

Global energy scenario requires thermal systems with higher efficiency and lower capital and operating cost. The paper deals with the thermoeconomic analysis of the gas turbine cycles with possible application as marine gas turbines. Thermoeconomic analysis of an energy conversion cycle is a combined study of thermodynamics and economics. Different configurations of gas turbine cycles have been analyzed using thermo-economic methodology keeping the gas turbine operating parameters (compressor pressure ratio, turbine inlet temperature, isentropic efficiencies of compressor & turbine etc fixed. Study has been carried out by considering appropriate objective function in a form of decision variables. This objective function combines both fuel cost and investment cost. Correlation functions having variables such as pressure ratio, isentropic efficiencies of compressor & turbine and turbine inlet temperature have been presented for obtaining capital cost for all equipments of the cycle.

In comparison to other thermal power cycles, gas turbine based energy conversion cycles exhibit superior thermodynamic performance as well as reduced emission. Gas turbine manufacturers and research & development (R&D) organizations are working on modification in basic gas turbine (BGT) cycle, which are intended to improve the basic gas turbine cycle thermodynamic performance and reduce emissions. The present work reports a comparison of thermodynamic performance, NOx and CO emission for basic and intercooled gas turbine (IcGT) cycles. Various cycle operating parameters such as compressor-pressure-ratio (rp,c), combustor-primary-zone-temperature, equivalence-ratio, and residence time of gas turbine based cycles has been examined. IcGT cycle exhibits higher gas turbine specific work and gas turbine efficiency in comparison to BGT cycle for the same rp,c and turbine rotor inlet temperature.

This paper focuses on the thermodynamic analysis of Solid Oxide fuel cell (SOFC). In the present work the SOFC has been modeled to work with internal reforming of fuel which takes place at high temperature and direct energy conversion from chemical energy to electrical energy takes place. The fuel-cell effluent is high temperature steam which can be used for co-generation purposes. Syn-gas has been used here as fuel which is essentially produced by steam reforming of methane in the internal reformer of the SOFC. A thermodynamic model of SOFC has been developed for planar cell configuration to evaluate various losses in the energy conversion process within the fuel cell. Cycle parameters like fuel utilization ratio and air-recirculation ratio has been varied to evaluate the thermodynamic performance of the fuel-cell. Output performance parameters like terminal voltage, cell-efficiency and power output have been evaluated for various values of current densities.