Multi-Fidelity Design Optimization of a Long-Range Blended Wing Body Aircraft with New Airframe Technologies

The German Cluster of Excellence SE²A (Sustainable and Energy Efficient Aviation) is established in order to investigate the influence of game-changing technologies on the energy efficiency of future transport aircraft. In this paper, the preliminary investigation of the four game-changing technologies active flow control, active load alleviation, boundary layer ingestion, and novel materials and structure concepts on the performance of a long-range Blended Wing Body (BWB) aircraft is presented. The BWB that was equipped with the mentioned technologies was designed and optimized using the multi-fidelity aircraft design code SUAVE with a connection to the Computational Fluid Dynamics (CFD) code SU2. The conceptual design of the BWB aircraft is performed within the SUAVE framework, where the influence of the new technologies is investigated. In the second step, the initially designed BWB aircraft is improved by an aerodynamic shape optimization while using the SU2 CFD code. In the third step, the performance of the optimized aircraft is evaluated again using the SUAVE code. The results showed more than 60% reduction in the aircraft fuel burn when compared to the Boeing 77

Aerodynamic Optimization of an UHBR Engine Position on a Short Range Aircraft Configuration at Cruise Flight Conditions

The trend towards more efficient engines with larger diameters is expected to continue for future commercial transport aircraft. One crucial aspect caused by the increasing engine size is the integration of the engine on the wing. This issue is being investigated in the European Project CleanSky2 within the platform Large Passenger Aircraft (LPA) by combining a conventional single-aisle aircraft with an ultra high-bypass ratio (UHBR) engine (Bypass ratio BPR=15). The work within this project focuses on the low-speed configuration during take-off and especially landing, because the large engine diameter and the close coupling of wing and engine leads to a shortened leading edge device in spanwise direction. This slat cut-back affects the high-lift performance adversely because of the locally missing leading edge device, which is crucial to reach the required lift coefficients. As a consequence, a mitigation needs to be devised to stabilizethe flow on the wing in the wake of the engine and recover the performance loss. A promising option is active flow control (AFC) to suppress a significant flow separation at relevant angles of attack. In order to study the low speed configuration, an optimization was set-up to generatea realistic UHBR single-aisle short-range configuration. Therefore, an optimization of the engine’s position along the wing was accomplished in cruise flight conditions. A subsequent optimization refined the obtained design through a shape adaptation of nacelle and pylon. This paper will cover the engine position optimization. For this purpose, a fully automated process chain including geometry adaptation, mesh generation, CFD calculation and evaluation was established. With the aid of a surrogate based optimizer, a design of experiments (DoE) was performed to investigate the influence of the horizontal distance, vertical distance, pitch and toe-in angle within a defined parameter space. An adaptive sampling approach following the DoE found the optimal engine position for minimum drag at cruise flight conditions

A complex equivalent source method for scattering effect of aircraft noise

An equivalent source method using equivalent monopoles in complex space is developed for calculating scattering effects for aircraft noise applications. The new method overcomes deficiencies in traditional equivalent real space source methods in treating scattering off thin sharp edges. While a traditional equivalent source method may fail in situations where either thin objects and/or objects with sharp edges exist, e.g. wings, the new method is able to deal with both bluff bodies and wings with relatively small thickness and sharp trailing edges. In this work, we describe the method in detail. Verification and assessment of capabilities of the method are performed using benchmark test cases

Conceptual design trade study for an energy-efficient mid-range aircraft with novel technologies

Present work demonstrates an initial conceptual design of a medium-range passenger aircraft featuring novel technologies being investigated under the German Cluster of Excellence SE2 A (Sustainable and Energy-Efficient Aviation). Novel aircraft and engine technologies include the hybrid laminar flow control, active load alleviation, boundary layer ingestion, ultra-high bypass ratio turbofan engines, and new materials and structures. To design such an aircraft, major trade studies and multi-disciplinary design optimization (MDO) were performed using a multi-fidelity analysis approach. The open-source aircraft design environment SUAVE was modified and integrated with other aircraft design and analysis tools to assess the performance of the aircraft equipped with the mentioned technologies and compared against the reference Airbus A320 aircraft. Results demonstrate reduction of the fuel burn by 43.6% with a forward-swept wing and by 36.7% with a backward-swept wing due to the benefits introduced by the novel technologies. © 2021, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved

The choice of absorbents for the purification of waste gases from soda production from hydrogen sulfide

Среди жидкостей, имеющихся в технологическом цикле производства кальцинированной соды, как перспективные абсорбенты для очистки сбросных газов от сероводорода была выбрана жидкость, содержащая карбонат натрия и аммиак, и раствор карбоната натрия в насыщенном растворе хлорида натрия. Показано, что по совокупности свойств, таких как скорость абсорбции, емкость по поглощаемому компоненту и селективность, содосоляной раствор является наиболее подходящим.Among the liquids available in the technological cycle for the production of soda ash, liquid containing sodium carbonate and ammonia and a solution of sodium carbonate in a saturated solution of sodium chloride were chosen as promising absorbents for purifying exhaust gases from hydrogen sulfide. It has been shown that in terms of a combination of properties, such as absorption rate, absorbent component capacity and selectivity, a soda-saline solution is most suitable