Mechanical Engineering Research; Vol. 8 No. 2; 2018 ISSN 1927-0607 E-ISSN 1927-0615

Published by Canadian Center of Science and Education

48

Design of Next Generation Civil and Military Aircraft with Ultra-High Bypass Engine using Composites, Advanced Materials and Technology

B. O. Akinnuli1 & O. J. Oladipo2 1 Department of Industrial and Production Engineering, The Federal University of Technology, Akure, Nigeria 2 Department of Mechanical Engineering, The Federal University of Technology, Akure, Nigeria Correspondence: B. O. Akinnuli, Department of Industrial and Production Engineering, The Federal University of Technology, Akure, Nigeria. E-mail: ifembola@yahoo.com Received: November 8, 2018 Accepted: November 20, 2018 Online Published: November 30, 2018 doi:10.5539/mer.v8n2p48 URL: https://doi.org/10.5539/mer.v8n2p48 Abstract Indirect combustion noise had not been attracting research in the past, but recent indication seems to prove that it could be a threat in the future if not addressed. Means of reducing this type of noise to a low decibel value was also included. Noise is due to the ingestion of distorted atmospheric turbulence, as the two set of blades rotate in different direction. Open rotor noise is higher since the rotors are fully exposed to oncoming turbulence and lack ducting or a nacelle to attenuate the radiated sound. A thorough review on the technology that can replace conventional turbofan was carried out. It was found that none of this technology can meet up with the ACARE and NASA 2020 vision but left a gap to be filled. Because open rotor is the most proven engine that is able to satisfy this requirements, different methods are adopted and integrated to reduce open rotor noise. Attention was paid to the geometry of the blade, hub and blade length, the vorticity and interaction noise are simulated until an optimized blade was achieved. The integration problem of open rotor was addressed where the engine was located to minimize perceive noise to the payload. Keywords: Aircraft, Composites, Noise, Open rotor, Advanced Technology 1. Introduction Aerospace engineering is an aspect of engineering that deals with the design, maintenance and improvement of aircraft by using knowledge and skills acquired through mathematics, physics, chemistry and natural science. An engineer trained by education and experience can be licensed to practice activities in the aerospace industry; such a professional is regarded as an aerospace engineer. The major activity in aeronautical profession is aircraft design. Aircraft design requires the integration of experts in disciplines including Aerodynamics, Propulsion, Structures, Flight mechanics, Avionics and Management (Sadraey, 2013). All experts in these fields must have the basic knowledge of engineering design techniques. Aircraft design is an analytical process; it requires creative and innovative mindset. The career goal of any aerospace engineer like other engineers in differ fields is to design aircraft that satisfactorily meets the market demand (Bello, 2018). Rapid technological advancement has been taken place in the aerospace sector since man first get to space through fixed wing airplane. Today’s innovation in aerospace focused on three main areas, these are Environmental impact, Economic efficiency and Improved passenger experience (Special focus, 2018). Environmental impact and economic efficiency are given preference in recent research because of the strict rules and regulations laid down by the regulatory bodies. Such include the Advisory Committee for Aeronautics and Research in Europe (ACARE), the National Aeronautics and Space Administration (NASA), the Intergovernmental Panel on Climate Change (IPCC), Committee on Aviation Environmental Protection (CAEP), Continuous Lower Energy, Emissions and Noise (CLEEN) among others (ACARE, 2003; IPCC, 1999; ICAO, 2007). A report from the Royal Aeronautical Society summarizes the challenges facing designers of next generation aircraft. “There are challenges facing the next generation aircraft as stricter environmental constraints and increasing pressure to reduce manufacturing and life-cycle costs mean the resulting aircraft will be complex, requiring the use of advanced or novel materials, multi-disciplinary design approaches and solutions operating in a distributed design environment” (RAeS, 2018). These regulations mean that next generation aircraft should be designed to contribute little or no pollution to the environment. This can be achieved using More Electric Engine (MEE), More Electric Aircraft (MEA) or any other aircraft engine that can satisfy these requirements (RAeS, 2018).

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mer.ccsenet.org Mechanical Engineering Research Vol. 8, No. 2; 2018

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