Luiz Felipe Pellegrini

Exergy Analysis Applied to a Complete Flight Mission of a Commercial Aircraft

†‡ § The aeronautical industry has evolved to design extremely complex aircraft, with highl y integrated systems. Commonly used methods to design and later optimize are based on trade -off studies, which are faulty in evaluating new systems, as they present lack of information. Previous work s have shown the applicability of exergy analysis as a de cision making tool to aircraft systems design and optimization. Besides locating and quantifying the sources of entropy generation, exergy analysis can relate these irreversibities with fuel consumption, and thus with operational cost of a mission. Followi ng the methodology developed in recent works, this paper presents an exergy analysis of a complete flight mission of a conventional commercial aircraft. Such analysis allows the evaluation of exergy efficiency and exergy destroyed rate for the whole flight , as well as for each one of the flight phases (climbing, cruise, descent, holding and landing).

More Electric Aircraft Analysis Using Exergy as a Design Comparison Tool

The more electric aircraft is an evolution of the aircraft industry to develop more efficient aircrafts in terms of fuel consumption and direct operational costs. One approach for a more electric aircraft is to substitute hydraulic and pneumatic power for electric power consumers: electric control surfaces actuators, cabin compressors for air conditioning and electric heaters for ice protection system. This paper describes the main characteristics of a more electric aircraft (MEA) and evaluates the exergy indexes for a complete flight cycle for the same aircraft. Previous works have shown the applicability of exergy analysis as a decision making tool to aircraft systems design and optimization. Such analysis allows the evaluation of exergy efficiency and exergy destroyed rate for the whole flight, as well as for each one of the flight phases.

A THERMODYNAMIC ANALYSIS OF DIFFERENT CONFIGURATIONS FOR COGENERATION USING RANKINE CYCLES IN BIOREFINERIES

Exergy analysis was applied to differents cogeneration Rankine cycles using biomass as fuel, aiming at evaluating the effect of increasing power production (electricity) and its maximization for the same demand of process steam. Moreover, it was studied the effect of different plant configurations units to meet certain need for process steam. To this aim, it will be proposed some modifications in the cycle in comparison with the standar configuration. Therefore, the use of reheating, preheating, condensing turbine, among others hybrid variation, are noteworthy for this type of analysis.