Performance of a Boundary Layer Ingesting (BLI) Propulsion System

Modelling of A Boundary Layer Ingesting Propulsor

“…Since it is a mature technology, new concepts such as boundary layer ingestion (BLI), which is closely connected to embedded engines, have to be taken into account to get a relevant benefit. Previous studies in this field revealed a promising potential for all kinds of aircraft concepts [3][4][5][6][7] and encouraged the present work. The intention was to develop a fast tool for basic performance analyses of a single propulsor in the presence of BLI and it should be decoupled from a concrete aircraft design.…”

“…Bauhaus Luftfahrt estimated the BLI benefit of different aircraft concepts and determined a PSC of up to 5.66 % for a blended wing body with top mounted engines [3]. The estimation based on system studies which did not account for drawbacks from fan efficiency, e.g., presented in [4]. In the same publication a more realistic approach considering fan interaction with inlet distortion showed the same trend of PSC for different amounts of ingested boundary layer.…”

Numerical Analysis of Effect of Boundary Layer Characteristics on the Flow Field in S-shaped Inlet

“…The study of flow characteristic of inlet started early abroad; however, the in-depth study of S-shaped inlet begins with a jet plane, and then has been applied on the cruise missile [4][5][6][7][8][9][10][11][12] . Plas [13] systematically studied the boundary layer suction for promoting the performance of the system, the results show that the boundary layer suction can reduce fuel consumption by a few percentage points, and the distortion along the piping is the main reason for the overall performance. Liu Zhenxia [14] analyzed the influence of former fuselage of S inlet on the entrance and the shock wave distribution of internal flow field based on the simulation of supersonic flow field.…”

Weight assessment for a blended wing Body-Unmanned aerial vehicle implementing boundary layer ingestion

“…In 2004, a design optimization of a BWB subsonic transport was developed by Liebeck [3]; in his work, BLI was evaluated experimentally, simulating the boundary layer over a flat plate and testing different duct geometries. A. Plas [4] assessed the performance of a BLI propulsion system; to evaluate the benefits of BLI in terms of energy, Plas considered power saving coefficient as figure of merit. For the "Silent aircraft", Plas estimated a power saving between 3% and 4% when embedding nacelles into the BWB airframe [4].…”

“…A. Plas [4] assessed the performance of a BLI propulsion system; to evaluate the benefits of BLI in terms of energy, Plas considered power saving coefficient as figure of merit. For the "Silent aircraft", Plas estimated a power saving between 3% and 4% when embedding nacelles into the BWB airframe [4].Campbell [5] and Carter [6] designed and tested 2 scale models of a BWB aircraft: a clean wing BWB, and a BWB with BLI nacelles. These studies determined aerodynamic coefficients for both configurations and evaluated the Propulsor-Airframe Integration (PAI) through computational fluid dynamics (CFD) and wind tunnel experiments at high Reynolds numbers about 75 million and a Mach number of 0.85 [6].…”