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Showing 1 to 19 of 19 for “"Boundary Layer Ingesting"”.
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Performance of a boundary layer ingesting propulsion system
… engines, in the presence of aircraft fuselage boundary layer ingestion (BLI). The emphasis is on defining the role that the turbomachinery (i.e., the fan, in the ultra high bypass engines considered) plays in establishing the flow benefit due to BLI. A three-dimensional body force approach to …
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Aerodynamics and Power Balance of Boundary Layer Ingesting Aircraft
By ingesting the fuselage Boundary Layer (BL) and re-energising it, Boundary Layer Ingestion (BLI) offers the potential for considerable fuel savings. However, it remains unclear which the most promising aircraft configuration for BLI is. Furthermore, the tight integration between the propulsor and …
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Boundary layer ingesting inlet design for a silent aircraft
… the airframe decreased, mainly due to a thicker boundary layer. Although further tailoring of the geometry is needed, the above guidelines should provide both direction and rationale for these alterations.
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Measurements of Flow in Boundary Layer Ingesting Serpentine Inlets
… systems featuring ingestion of the airframe boundary layer offer reduced noise, emissions, and fuel consumption. Embedded engine systems are envisioned which require boundary layer ingesting (BLI) serpentine inlets to provide the needed air ow to the engine. These inlets produce distorted …
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Active Flow Control of a Boundary Layer Ingesting Serpentine Diffuser
The use of serpentine boundary layer ingesting (BLI) diffusers offers a significant benefit to the performance of Blended Wing Body aircraft. However, the inherent diffuser geometry combined with a thick ingested boundary layer creates strong secondary flows that lead to severe flow distortion at …
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Design of a model propulsor for a boundary layer ingesting aircraft
… of an advanced civil transport aircraft with boundary layer ingestion (BLI). The electrically powered single-stage propulsors represent the ultra-high bypass ratio turbofan engines on a full-scale conceptual aircraft previously designed at MIT. Powered models will use these propulsors in both …
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A Tail-Integrated Boundary-Layer Ingesting Propulsion System for Turbo-Electric Aircraft
… system for turbo-electric aircraft with boundary layer ingestion (BLI). This includes (i) definition of tail BLI electric fans and (ii) integration of the BLI propulsors on an aircraft tail, to meet the propulsive power requirements and performance goals, i.e. separation-free and …
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Full Scale Experimental Transonic Fan Interaction with a Boundary Layer Ingesting Total Pressure Distortion
… flow introduced to the engine through boundary layer ingesting (BLI) inlets, creating a different operational environment from which the engines were originally designed. The goal of this study was to explore the effects such non-uniform flow would have on the behavior and performance …
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Measurement and Uncertainty Analysis of Transonic Fan Response to Total Pressure Inlet Distortion
… pressure distortion profile representative of a boundary-layer ingesting (BLI) embedded engine. The goal was to make a series of flow measurements that contribute to the overall physical understanding of this complex flow situation. Proper uncertainty analysis is critical to extracting meaning …
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Topics on conceptual design of the D8 aircraft : fuel burn uncertainty estimate and BLI propulsor loss modeling
… mounted engines that ingest part of the fuselage boundary layer. This fuel burn benefit is determined to be (18.0 ± 2.2)% for aircraft with a cruise Mach of 0.72 and (20.1 ± 2.6)% for aircraft with a cruise Mach of 0.78. The benefit is shown to be robust to changes in technology assumptions and …
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Analysis of civil aircraft propulsors with boundary layer ingestion
… for fan turbomachinery conceptual design, for a boundary layer ingesting (BLI) propulsion system for advanced civil transport aircraft. For the former, configuration performance analysis shows BLI yields a reduction in mechanical power required to propel a given aircraft. For the latter, fan …
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Trade space assessment of electrified commercial aircraft
… timeframe. The propulsive power reduction from boundary layer ingestion (BLI), a technology that could be enhanced by electrification, is characterized and bounded by power balance analysis. An aircraft system model extends this analysis to capture the weight and performance trades of …
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Stereoscopic Particle Image Velocimetry Measurements of Swirl Distortion on a Full-Scale Turbofan Engine Inlet
… inlet swirl distortion profile that mimics boundary layer ingesting inlets was generated by a novel new method, dubbed the StreamVane method, and measured in a sub scale tunnel using stereoscopic particle image velocimetry (SPIV) as a precursor for swirl distortion generation and …
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The power balance method For aerodynamic performance assessment
… for integrated configurations such as boundary layer ingesting (BLI) aircraft. The thesis provides evidence of the major benefits of the power balance method, and descriptions of its limitations, for three applications: 1) derivation of an analytic expression of profile drag estimates …
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Inlet swirl distortion effects on the generation and propagation of fan rotor shock noise
… a fan installed in a conventional inlet and in a boundary-layer-ingesting serpentine inlet for a free-stream Mach number of 0.1. The key effect of boundary layer ingestion is the creation of streamwise vorticity which is ingested into the inlet, resulting in co- and counter-rotating streamwise …
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Experimental Investigation of Fan Rotor Response to Inlet Swirl Distortion
… One such design concept incorporates boundary layer ingestion which locates the turbofan engine inlet near enough to the lifting surface of the aircraft skin that the boundary layer is ingested and reenergized. This process reduces overall aircraft drag and associated required thrust, …
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Methodology Development and Investigation of Turbofan Engine Response to Simultaneous Inlet Total Pressure and Swirl Distortion
… using computational analysis of a conceptual boundary layer ingesting S-duct turbofan engine inlet. The resulting inlet distortion profile, consisting of both total pressure and swirl distortion elements, was used as the objective profile to be matched by the ScreenVane in a turbofan engine …
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Effect of BLI-Type Inlet Distortion on Turbofan Engine Performance
Boundary Layer Ingestion (BLI) is currently being researched as a potential method to improve efficiency and decrease emissions for the next generation of commercial aircraft. While re-energizing the boundary layer formed over the fuselage of an aircraft has many system level benefits, ingesting …
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Assessment of an Innovative Experimental Facility for Testing Diffusing Serpentine Inlets with Large Amounts of Boundary Layer Ingestion
… ground test facility was able to simulate the boundary layer profile expected to be ingested by inlets mounted on the aft sections of these aircraft. It generated Mach numbers ranging from 0.19 to 0.4 and boundary layer thicknesses between 36% and 45%. The circumferential distortions at the …