Assessment of Civil Aircraft Certification and Component-Level Noise During Landing Take-off Cycle

摘要

This paper implements an integrated aircraft preliminary noise assessment framework, targeting the certification and component level noise estimation of an existing civil aircraft architecture. Through the successful deployment of the proposed framework, an aircraft model representative of a modern commercial aircraft carrier has been investigated, operating under representative landing and take-off conditions. The deployed aircraft-powerplant configuration is modelled to match the design and performance characteristic of the Airbus A321-231 aircraft equipped with V2533-A5 engine. The operational procedures employed for the design and modelling of the LTO cycle represent typical modern day aircraft take-off and approach operation, and adhere with the ICAO defined noise estimation certification standards. The designed case study is implemented to assess the entire range of the ICAO certification data corresponding to the A321-231 aircraft family variants. This is achieved by modelling two representative variants of the A321-231 aircraft configuration; (i) A231-231 aircraft corresponding to the upper limit of the certified maximum take-off weight (MTOW), and maximum landing weight (MLW), (ii) A321-231 aircraft corresponding to the lower limit of the certified MOTW and MLW. The acquired results from the overall assessment are presented and discussed in three dedicated parts. First, the employed engine model design and performance characteristics are modelled and evaluated at both engine and operational level. The engine model results are verified against the ICAO engine emissions data, European Aviation Safety Agency (EASA) aircraft certification data, Electronic Engine Control (EEC) data, and against the data acquired through the Airbus Performance Engineers' Program (PEP). The engine component thermodynamic and performance parameters (i.e. temperature, pressure, mass flow, tip Mach numbers, jet velocities) are derived and discussed corresponding to each flight segment of the LTO cycle. Secondly, the aircraft design and performance characterises corresponding to all flight segments of the LTO cycle are derived, and subsequently deployed to model the take-off and approach flight path trajectories corresponding to both configurations. Finally, through the successful deployment of the proposed overall methodology, the acquired aircraft certification noise level results are presented and verified against the ICAO noise certification measurement data. The model predictions exhibit good agreement with the ICAO noise certification measurement data at all three certification points. The results acquired for take-off noise certification suggest that the maximum take-off weight of the aircraft have a major impact on the aircraft take-off and climb performance, and thus have a dominant impact on lateral and flyover noise. The derived component level results corresponding to all three certification points suggest that, at lateral and flyover certification points, due to the high engine thrust settings, the fan and jet noise are the most dominant noise sources. Whereas, during approach the overall airframe noise is the most dominant noise source. The deployed methodology can essentially be regarded as an enabling technology to support the preliminary noise assessment of existing and advanced civil aircraft architectures.