Turbofan

About: Turbofan is a research topic. Over the lifetime, 4114 publications have been published within this topic receiving 39490 citations. The topic is also known as: fanjet & turbofan engine.

Aerodynamic Design of a New Five Stage Low Pressure Turbine for the Rolls Royce Trent 500 Turbofan

Abstract: Almost a decade ago, ITP (Industria de Turbo Propulsores, S.A.) started to participate in Low Pressure turbine design supported by Rolls-Royce. The Trent 500 LP turbine aerodynamic design is the most challenging and extensive design work carried out to the moment.The Trent 500 is part of the Rolls Royce Trent family. It has been designed to enter in service in the Airbus 340-600. This engine has very aggressive targets in terms of cost, performance, weight and noise. An optimization process was carried out during the preliminary and detailed design phases to accomplish these targets.This paper describes the most outstanding characteristics of the LP turbine, how the previous experience and Research and Technology results have been employed in this design and also some of the new advanced features, e.g. the introduction of spoon aerofoils.Copyright © 2001 by ASME

Experimental Analysis of the Global Performance and the Flow Through a High-Bypass Turbofan in Windmilling Conditions

Abstract: A detailed study of the air flow through the fan stage of a high-bypass, geared turbofan in windmilling conditions is proposed, to address the key performance issues of this severe case of off-design operation. Experiments are conducted in the turbofan test rig of ISAE, specifically suited to reproduce windmilling operation in an ambient ground setup. The engine is equipped with conventional measurements and radial profiles of flow quantities are measured using directional five-hole probes to characterize the flow across the fan stage and derive windmilling performance parameters. These results bring experimental evidence of the findings of the literature that both the fan rotor and stator operate under severe off-design angle-of-attack, leading to flow separation and stagnation pressure loss. The fan rotor operates in a mixed fashion: spanwise, the inner sections of the rotor blades add work to the flow while the outer sections extract work and generate a pressure loss. The overall work is negative, revealing the resistive loads on the fan, caused by the bearing friction and work exchange in the different components of the fan shaft. The parametric study shows that the fan rotational speed is proportional to the mass flow rate, but the fan rotor inlet and outlet relative flow angles, as well as the fan load profile, remain constant, for different values of mass flow rate. Estimations of engine bypass ratio have been done, yielding values higher than six times the design value. The comprehensive database that was built will allow the validation of 3D Reynolds-averaged Navier–Stokes (RANS) simulations to provide a better understanding of the internal losses in windmilling conditions.

New technique for the direct measurement of core noise from aircraft engines

Abstract: A new technique is presented for directly measuring the core noise levels from gas turbine aircraft engines. The technique requires that fluctuating pressures be measured in the far-field and at two locations within the engine core. The cross-spectra of these measurements are used to determine the levels of the far-field noise that propagated from the engine core. The technique makes it possible to measure core noise levels even when other noise sources dominate. The technique was applied to signals measured from an AVCO Lycoming YF102 turbofan engine. Core noise levels as a function of frequency and radiation angle were measured and are presented over a range of power settings.

Performance analysis of an electrically assisted propulsion system for a shortrange civil aircraft

Abstract: With civil aviation growing at around 4.7% per annum, the environmental footprint of aviation is increasing. Moreover, the use of kerosene as a fuel accelerates the depletion of non-renewable fossil fuels and increases global warming. Hence, the aviation industry has to come up with new technologies to reduce its environmental impact and make aviation more sustainable. An electrically assisted propulsion system can combine the benefits of an electrical power source with a conventional turbofan engine. However, the additional electrical system increases the weight of the aircraft and complexity of the power management system. The objective of this research is to analyze the effect of an assistive electrical system on the performance of a turbofan engine for an A320 class aircraft on a short-range mission. The developed simulation model consists of an aircraft performance model combined with a propulsion model. The power management strategy is integrated within the simulation model. With the proposed propulsion system and power management strategy, the electrically assisted propulsion system would be able to reduce fuel burn, total energy consumption, and emissions for short-range missions of around 1000 km.